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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                              Washington, DC 20549
                                    _________

                                    FORM 10-K

(Mark One)
[X] Annual report pursuant to Section 13 or 15(d) of the Securities Exchange Act
    of 1934 for the fiscal year ended December 31, 2000

                                       or

[_] Transition report pursuant to Section 13 or 15(d) of the Securities Exchange
    Act of 1934 for the transition period from _____________ to ______________

                         Commission File Number 0-23441

                                    _________

                            POWER INTEGRATIONS, INC.
             (Exact name of registrant as specified in its charter)

                 DELAWARE                                        94-3065014
      (State or other jurisdiction of                         (I.R.S. Employer
       Incorporation or organization)                        Identification No.)

               5245 Hellyer Avenue San Jose, California      95138-1002
               (Address of principal executive offices)      (Zip code)

                                 (408) 414-9200
              (Registrant's telephone number, including area code)

             Securities registered pursuant to Section 12(b) of the Act:

          Title of each class              Name of Exchange on which registered
          -------------------              ------------------------------------
                None                                        None

          Securities registered pursuant to Section 12(g) of the Act:

                        Common Stock, $0.001 par value
                                (Title of Class)

                                    _________

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES [X] NO [_]
     Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. [_]
     The aggregate market value of registrant's voting and non-voting common
equity held by nonaffiliates of registrant, based upon the closing sale price of
the common stock on February 28, 2001, as reported on the NASDAQ National
Market, was approximately $294,233,323. Shares of common stock held by each
officer, director and holder of 5% or more of the outstanding common stock have
been excluded in that such persons may be deemed to be affiliates. This
determination of affiliate status is not necessarily a conclusive determination
for other purposes.
     Outstanding shares of registrant's common stock, $0.001 par value, as of
February 28, 2001: 27,565,133.

                      DOCUMENTS INCORPORATED BY REFERENCE

     Parts of the definitive Proxy Statement for registrant's 2001 Annual
Meeting of Stockholders to be filed with the Commission pursuant to Regulation
14A not later than 120 days after the end of the fiscal year covered by this
Form are incorporated by reference into Part III of this Form 10-K Report.

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                               TABLE OF CONTENTS


                                    PART I



                                                                                                              Page
                                                                                                              ----
                                                                                                          
ITEM 1.          BUSINESS.....................................................................................  3

ITEM 2.          PROPERTIES................................................................................... 16

ITEM 3.          LEGAL PROCEEDINGS............................................................................ 16

ITEM 4.          SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS.......................................... 16


                                                     PART II

ITEM 5.          MARKET FOR POWER INTEGRATIONS COMMON EQUITY AND RELATED STOCKHOLDER MATTERS.................. 17

ITEM 6.          SELECTED FINANCIAL DATA...................................................................... 18

ITEM 7.          MANAGEMENTS DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND OPERATING RESULTS............. 19

ITEM 7a.         QUANTITIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISKS.................................... 30

ITEM 8.          CONSOLIDATED FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA..................................... 30

ITEM 9.          CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE......... 30

                                                     PART III

ITEM 10.         DIRECTORS AND EXECUTIVE OFFICERS OF THE COMPANY.............................................. 31

ITEM 11.         EXECUTIVE COMPENSATION....................................................................... 31

ITEM 12.         SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT............................... 31

ITEM 13.         CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS............................................... 31

                                                     PART IV

ITEM 14.         EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K.............................. 32

SIGNATURES.................................................................................................... 51


                                       2


PART I

     This report includes a number of forward-looking statements. Such
statements reflect our current views with respect to future events and our
potential financial performance and are subject to risks and uncertainties that
could cause our actual results and financial position to differ materially from
what we say in this report. These factors include, but are not limited to, our
ability to maintain and establish strategic relationships; the risks inherent in
the development and delivery of complex technologies; our ability to attract,
retain and motivate qualified personnel; the emergence of new markets for our
products and services, and our ability to compete in those markets based on
timeliness, cost and market demand; and our limited financial resources. We more
fully discuss these and other risk factors in "Item 7--Management's Discussion
and Analysis of Financial Condition and Operating Results--Factors That May
Affect Future Results of Operations" and elsewhere in this report.

     TOPSwitch, TinySwitch and EcoSmart are trademarks of Power Integrations,
Inc.

Item 1. Business

Overview

     We design, develop, manufacture and market proprietary, high-voltage,
analog integrated circuits, commonly referred to as ICs, for use primarily in
alternating current to direct current, or AC to DC, power conversion. We have
targeted high-volume power supply markets including:

     .    the cellular telephone market;

     .    the personal computer market;

     .    the cable and direct broadcast satellite decoder box market; and

     .    various other consumer and industrial electronics markets.

     Our ICs cost-effectively bring the benefits of high levels of integration
to AC to DC switching supplies. We believe that the products in our TOPSwitch
family of high-voltage ICs, introduced in 1994, were the first highly integrated
power conversion ICs to achieve widespread market acceptance. We introduced
TOPSwitch II, an enhanced family of our ICs, in April 1997, TinySwitch, a family
of more energy-efficient power conversion ICs, in September 1998, TOPSwitch FX,
a family with greater design flexibility, in March 2000 and TOPSwitch GX, a
family capable of supplying output levels from 6 to 250 watts, in November 2000.

Industry Background

     Virtually every electronic device that plugs into a wall socket requires
some type of power supply to convert high-voltage AC, provided by electric
utilities, into low-voltage DC required by the devices. Additionally,
rechargeable, portable products, such as cellular phones and laptop computers,
also need an AC to DC power supply to recharge their batteries.

     Before 1970, AC to DC power supplies used large, inefficient transformers,
which operated at low frequencies to convert power from AC to DC. In the 1970s,
the invention of high-voltage discrete semiconductors enabled the development of
a new generation of AC to DC "switching" power supplies, which allowed the use
of smaller, more efficient transformers to lower the voltage. Although these
discrete switchers offered advantages over older technologies, over the years
they have not kept pace with the technological advances made in the electronic
devices they power.

     As the pressures from market forces have increased, the limitations of
discrete switchers have become more pronounced. Discrete switchers require
numerous components which limit the power supply designers' ability to reduce
the size, increase the functionality and improve the efficiency of switchers
while at the same time meeting stringent market cost and energy efficiency
requirements. In addition, discrete switchers involve a high level of

                                       3


design complexity, which limits the scalability of designs and increases
time-to-market and development risks for new products.

     Early attempts to replace discrete switchers with integrated switchers,
using high-voltage analog ICs, did not achieve widespread acceptance in the
marketplace because they were not cost-effective. We addressed this opportunity
in 1994 by introducing our first cost effective IC, TOPSwitch. Our growth since
that time validates our belief that a substantial market opportunity exists for
high-voltage ICs that are cost effective and combine the benefits of integration
that discrete switcher and earlier transformer technologies lack.

Our Highly Integrated Solution

     We have developed several families of high-voltage power conversion ICs,
which we believe are the first highly integrated power conversion ICs to achieve
widespread market acceptance. Since introducing our TOPSwitch family of products
in 1994, we have shipped approximately 525 million TOPSwitch ICs. These patented
ICs achieve a high level of system integration by combining a number of
electronic components into a single IC. Our TOPSwitch and TinySwitch products
enable many power supplies in the 0.5 to 150-watt power range to have a total
cost equal to or lower than discrete switchers. Our TOPSwitch and TinySwitch
products offer the following key benefits to power supplies:

        .  Fewer Components, Reduced Size and Enhanced Functionality

           Our highly integrated TOPSwitch ICs enable the design and production
           of cost-effective switchers that use up to 50% fewer components and
           have enhanced functionality compared to discrete-based solutions. For
           example, our ICs provide thermal and short circuit protection without
           increasing system cost, while discrete switchers must add additional
           components and cost to provide these functions.

        .  Improved Efficiency

           Our integrated circuit also improves electrical efficiency, which
           reduces power consumption and excess heat generation. Our patented
           low-loss, high-voltage device, combined with its control circuitry,
           improves overall electrical efficiency during both full operation and
           stand-by mode.

        .  Reduced Time-to-Market

           Our integrated circuit makes power supply design simpler and once
           customers have created designs using our ICs, they can apply that
           design to new products, resulting in a shorter time-to-market and
           reduced product development risk.

        .  Wide Power Range and Scalability

           Products in our current TOPSwitch families can address a power range
           of 0.5 to 150 watts. The scalable architecture of these ICs allows
           switcher designers to adapt their existing TOPSwitch-based designs to
           a wide range of products to address many different power supply
           markets.

Strategy

     Our objective is to be the leading provider of high-voltage power
conversion ICs. We intend to pursue the following strategies to accelerate
adoption of our products:

        .  Target High-Volume Markets

           Because of our products' scalability and ability to address a wide
           power range, a small number of products address a wide variety of
           customer needs, allowing us to take advantage of economies of scale
           and making us more competitive.

                                       4


        .  Focus on Markets that Can Derive Significant Benefits from
           Integration

           We are initially focusing our efforts on those markets that are
           particularly sensitive to size, portability, energy efficiency and
           time to market issues. We achieved early success in the cellular
           phone fast charger market, as cellular phone customers demanded more
           portable travel chargers instead of stand-alone desktop chargers. We
           have also achieved some success in the desktop PC market due to the
           market's demand for stand-by power capability, and in the cable and
           direct broadcast satellite decoder box market due to that market's
           need for reducing component count and for shortening product design
           cycles. As other markets emerge as significant opportunities for our
           TOPSwitch products, we intend to focus our resources on the
           development and penetration of those markets.

        .  Deliver Systems Solutions and Provide Applications Expertise

           To help potential customers decide to purchase our TOPSwitch
           products, we offer comprehensive application design support. We
           provide extensive application notes and production-ready reference
           design boards. We also provide application-engineering support out of
           our headquarters and through field application engineering labs
           located in China, England, Germany, India, Japan, Korea and Taiwan.
           We have committed substantial resources to system support by
           dedicating approximately one-third of our technical workforce to
           applications engineering. We believe our power supply systems
           expertise and investment in field applications engineering provide us
           significant competitive advantages.

        .  Extend Technological Leadership in High-Voltage Analog ICs

           Our proprietary device structures and fabrication processes as well
           as analog circuit designs have resulted in 29 U.S. patents and 56
           foreign patents. These patents, in combination with our other
           intellectual property, form the basis of our TOPSwitch and TinySwitch
           product families. We recently introduced an enhanced TOPSwitch
           product family that provides improved power capability and system
           cost advantages while preserving the design simplicity of our
           original TOPSwitch products. We continue to improve our device
           structures, wafer fabrication processes and analog circuit designs
           and seek to obtain additional patents to protect our intellectual
           property.

        .  Leverage Patented Technology in Strategic Relationships

           We have established relationships with Matsushita Electronics
           Corporation, and with OKI Electric Industry in order to take
           advantage of these companies' high volume manufacturing resources,
           and in the case of Matsushita, generate royalty revenues. Our wafer
           manufacturing relationships with Matsushita and OKI enable us to
           focus on fundamental high-voltage silicon technology, product design
           and marketing while minimizing fixed costs and capital expenditures.
           Matsushita also has licensed the right to manufacture our products
           for sale in certain geographic regions and for use in its own
           products.

Products

     Below is a brief description of our products:

        .  TOPSwitch Product Families

           Our TOPSwitch high-voltage analog IC products are able to meet the
           power conversion needs of a wide range of applications within high
           volume markets. Sales of TOPSwitch products accounted for 98%, 97%
           and 95% of our net revenues in 2000, 1999 and 1998, respectively.

               .  TOPSwitch

                                       5


                  The TOPSwitch family was introduced in 1994 and consists of 13
                  products. The key benefits of the TOPSwitch family compared to
                  discrete switchers include fewer components, reduced size,
                  enhanced functionality and lower cost in many applications.
                  Our TOPSwitch products integrate a PWM controller, a high-
                  voltage MOSFET and a number of other electronic components
                  into a single 3 terminal IC. These products are produced in
                  two high-voltage versions--a 350-volt version for the 115VAC-
                  switcher markets, including the United States and Japan, and a
                  700-volt version for the 230VAC-switcher markets, including
                  Europe.

               .  TOPSwitch II

                  The TOPSwitch II family was introduced in April 1997 and
                  consists of 11 products. The TOPSwitch II products further
                  lower the switcher costs by improving the performance of
                  TOPSwitch and addressing low power applications. The TOPSwitch
                  II family uses the same proprietary architecture as the
                  original TOPSwitch family, enabling switcher designers
                  experienced with TOPSwitch to take advantage of the TOPSwitch
                  II benefits without implementing a new architecture.

               .  TinySwitch

                  The TinySwitch family was introduced in September 1998 and
                  consists of 5 products. The product line topology was
                  specifically designed to address low power applications below
                  10 watts. The TinySwitch family of high voltage ICs was the
                  first family of chips to incorporate EcoSmart technology to
                  address the growing global demand to reduce energy waste in a
                  wide range of electronic products. It dramatically reduces the
                  energy consumed during standby and no-load enabling our
                  customers to meet governmental energy efficiency guidelines.

               .  TOPSwitch-FX

                  The TOPSwitch-FX family was introduced in March 2000 and
                  consists of 6 products. This family offers engineers greater
                  design flexibility to develop highly integrated power
                  supplies. New features integrated into the TOPSwitch-FX parts
                  continue to reduce the system cost of power supplies as well
                  as improve their performance. In addition, this product line
                  incorporates our energy saving EcoSmart technology to help
                  meet the growing need for environmentally friendly power
                  solutions. The family delivers up to 75 watts of power for use
                  in markets such as cellular phone chargers, personal
                  computers, set-top boxes and DVD players.

               .  TOPSwitch-GX

                  The TOPSwitch-GX family was introduced in November 2000 and
                  consists of 11 products capable of supplying output power
                  levels from 6 watts to 250 watts. TOPSwitch-GX is the first
                  monolithic high voltage switching power IC capable of
                  providing this level of power. The new family incorporates the
                  features offered in earlier TOPSwitch product families as well
                  as new ones through additional user configurable pins. This
                  allows a higher level of end user design flexibility,
                  resulting in improved power supply design optimization and
                  lower system cost. Advanced EcoSmart technology offers
                  improved standby energy efficiency. Applications for
                  TOPSwitch-GX devices include laptop adapters, LCD monitors,
                  printers, desktop computers, Internet appliances, DVD players
                  and uninterruptible power supplies.

                                       6


        .  Other Products

           Our products also include our SMP family, our INT family and a
           limited number of custom products. Sales of these products accounted
           for 2%, 3% and 5% of our net revenues in 2000, 1999 and 1998,
           respectively. We expect revenue from these products to continue to
           decline as a percentage of net revenues.

               .  SMP

                  The SMP family is the original line of power conversion
                  products, which we developed for the AC to DC power supply
                  market. These products are used in applications where switcher
                  designers are willing to pay a premium price for additional
                  features such as variable frequency.

               .  INT

                  The INT products are interface drivers for motor control
                  applications, which utilize our high-voltage process
                  technology.

               .  Custom Products

                  We also manufacture a limited number of custom products,
                  including a hook switch for telephones.

                                       7


Markets and Customers

     Our strategy is to target high-volume power supply markets and to initially
focus on markets that can benefit the most from our highly integrated power
conversion ICs. The following chart shows representative customers and end users
of our products in power supplies in several major market segments.



Market Segment                                       Customers
- ---------------------------------------              ---------------------------------------
                                                  
        .  Cellular Phones

               Battery Chargers                      Eastcom, Ericsson Hyundai, ICC, Lucky
                                                     Goldstar, Motorola and its subsidiaries,
                                                     Mitsubishi, Nokia, Phihong Enterprises,
                                                     Sagem, Salom, Samsung Electronics

        .  Desktop Computers

               Stand-by Power                        Acbel (API), Artesyn, Astec, Compaq,
                                                     Dell, Delta Electronics, Hewlett
                                                     Packard, Hipro, IBM, Intertek, Likom,
                                                     Liteon, Minebea, Magnetek, SPI,
                                                     Samsung, Seventeam, Sirtec Tiger

        .  Cable and Direct Broadcast Satellite

               Set-top Decoders                      Acbel (API), Amstrad, General
                                                     Instruments, Grundig, Hughes, Magnetek,
                                                     Motorola, Nokia, Pace, Pioneer,
                                                     Samsung, Scientific Atlanta, Sony, UEC,
                                                     Vestelcom

        .  PC Peripherals

               Multi-media Monitor & Audio           Altec, In-Focus,Compaq, Harman, JBL, Logitech,
                                                     Lucky Goldstar, Sony
               Universal Serial Bus                  LG, Samsung, Sony
               Removable Mass Storage                Iomega, Seagate

        .  Consumer

               TV                                    Daewoo, Hitachi, Lucky Goldstar, Nokia, Philips,
                                                     Samsung, Sharp, Sony,  Vestel, Xocexo, Zenith
               VCR                                   Aiwa, Daewoo, Sony
               DVD                                   Amoisonic, Orient Power, Shinco, Thakral

        .  Industrial

               Utility Meters                        Brainchild, Schlumberger, Siemens, Whisper
               Uninterruptible Power Supply          APC, Exide Electronics, Powerware, Rompower

        .  Home Appliances

               Washing Machines, Air                 AKO-Werke, Bosch-Siemens, Changhong, Fisher-Paykel,
               Conditioners, Dish                    General Electric, Hualing, Kelon, Lucky Goldstar,
               Washers, Vacuum                       Meide, Miele, Samsung, Shanghai Sinyuan, Whirlpool
               Cleaners


                                       8


 Description of Our Primary Markets

        .  Cellular Phone Chargers

           In the cellular phone market, size, portability and more recently,
           energy efficiency are key market drivers for these products. We
           believe a substantial market opportunity exists for small, energy
           efficient power supplies for battery chargers. We estimate the total
           available annual market for cell phone chargers was approximately 500
           million units in 2000.

        .  Desktop Computer Standby Power Supplies

           Governmental authorities are promoting computer manufacturers to use
           highly efficient stand-by power in new PCs to reduce the PCs' power
           consumption when idle. Our TOPSwitch and TinySwitch products are
           currently being used in computers to reduce the power consumed when
           idle and to meet the market demand for more energy-efficient
           computers. We estimate that the annual market for standby power
           supplies for desktop PCs was approximately 110 million units in 2000.

        .  Cable and Direct Broadcast Satellite Decoder Boxes

           Cable and direct broadcast satellite decoder box manufacturers are
           particularly sensitive to component count, set-top box size and the
           ability to shorten their product design cycles. Our TopSwitch
           products are currently helping them solve these problems and provide
           other benefits inherent with an integrated solution. We estimate that
           the annual market for power supplies in cable and direct broadcast
           satellite decoder boxes was approximately 40 million units in 2000.

        .  Other Markets

           Although we currently focus on the above key markets, we also sell
           products into a wide variety of other markets, which include PC
           peripherals, modems, televisions, VCRs, DVD players, industrial
           meters and home appliances. As these and other markets emerge as
           significant opportunities for our IC products, we intend to focus our
           resources on the development and penetration of these markets.

Sales, Distribution and Marketing

     We sell our products to original equipment manufacturers, OEMs, and
merchant power supply manufacturers through a direct sales staff and through a
worldwide network of independent sales representatives and distributors.. Our
international sales representatives also act as distributors in Europe and Asia.
In the United States, we use two national distributors and a number of regional
sales representatives. We have sales offices in Corona Del Mar, California,
Marietta, Georgia, Bloomingdale, Illinois, and Wakefield, Massachusetts, as well
as in China, England, Germany, India, Japan, Korea and Taiwan. For 2000, direct
sales to OEMs and merchant power supply manufacturers represented approximately
50% of our net revenues while sales through distributors accounted for the
remaining 50%. All distributors are entitled to certain return privileges based
on sales revenue and are protected from price reductions affecting their
inventories. Our distributors are not subject to minimum purchase requirements
and the sales representatives and distributors can discontinue marketing any of
our products at any time.

     Our products are generally incorporated into a customer's power supply at
the design stage. Our sales and marketing efforts are focused on facilitating
the customer's use of our products in the design of new power supplies for
specific applications. An important competitive factor in determining whether a
customer decides to use our products in its designs is our commitment to provide
comprehensive application design support. We publish comprehensive databooks and
design guides, and provide to our current and prospective customers extensive
application notes and production-ready reference design boards. In addition, we
provide application-engineering support out of our headquarters, and our field
application engineering labs provide local resources to support customers in key
geographies. We focus particular efforts on building relationships with, and
providing support to, industry-leading OEMs and merchant power supply
manufacturers. We have committed substantial

                                       9


resources to system support by dedicating approximately one-third of our
technical workforce to applications engineering.

     Our end user base is highly concentrated, and a relatively small number of
OEMs, directly or indirectly through merchant power supply manufacturers,
accounted for a significant portion of our revenue in 2000 and 1999. We estimate
that our top ten customers, including distributors which resell to large OEMs
and merchant power supply manufacturers, accounted for 69%, 68% and 67% of our
net revenues for 2000, 1999 and 1998, respectively. For 2000, Maxisum (Insight),
and Synnex Technologies, both distributors, accounted for 22% and 10% of our net
revenues, respectively. For 1999, these two distributors accounted for 16% and
11% of our net revenues, respectively. For 1998, Maxisum and Synnex accounted
for 22% and 13% of our net revenues, respectively. No other customers accounted
for more than 10% of net revenues during 2000, 1999 and 1998. In 2000, 1999 and
1998, international sales comprised 84%, 78% and 83%, respectively, of our net
revenues.

     Sales of our products are generally made pursuant to standard purchase
orders, which are frequently revised to reflect changes in the customer's
requirements. Product deliveries are scheduled upon our receipt of purchase
orders. Generally, these orders allow customers to reschedule delivery dates and
cancel purchase orders without significant penalties. For these reasons, we
believe that purchase orders received, while useful for scheduling production,
are not necessarily reliable indicators of future revenues.

     In the Japanese market, we have a license agreement with Matsushita under
which Matsushita sells its versions of our products. While we continued to sell
products to our existing Japanese customers, in April 1997, as part of the
license agreement, we agreed not to pursue new business in Japan until after
June 2000. Our new license agreement with Matsushita, effective July 2000, does
not have this restriction and we have begun to market our products again in
Japan. We will continue to support our Japanese customers through our office in
Japan.

Technology

        .     High-Voltage Transistor Structure and Process Technology

              We have developed a patented high-voltage, power IC technology,
              which uses our proprietary high voltage MOS transistor structure
              and fabrication process and has resulted in 8 U.S. patents. The
              technology enables us to integrate cost effectively on the same
              monolithic IC, high-voltage n-channel transistors with industry
              standard CMOS and bipolar components. The IC device structure and
              the wafer fabrication process both contribute to the cost
              effectiveness of our high-voltage technology. Recently introduced
              novel, high-voltage technology further improves silicon efficiency
              of the devices by using dual-conduction layers. The device
              structure provides a transistor conduction capability that results
              in a significantly more cost-effective high voltage device than
              that of competing technologies. Our high voltage ICs have been
              implemented on low cost silicon wafers using standard 5V silicon
              processing techniques combined with our proprietary implant
              process step, with relatively large feature sizes, up to a
              3-micron CMOS process.

        .     IC Design and System Technology

              Our proprietary IC designs combine complex control circuits and
              high-voltage transistors on the same monolithic IC and have
              resulted in 19 U.S. patents. Our IC design technology takes
              advantage of our high-voltage process to minimize the die size of
              both the high-voltage device and control circuits and improve the
              performance of our ICs versus alternative integration
              technologies. We also have developed system expertise in switching
              converters that have resulted in new innovative topologies that
              reduce system cost, increase system performance and greatly
              improve energy efficiency of power supplies compared to
              alternative approaches. The combination of our IC design
              technology and our system level expertise in switcher converters
              has enabled us to develop revolutionary products such as the
              highly integrated TOPSwitch, TOPSwitch-GX and TinySwitch family of
              ICs and scalable architecture for integrated switchers.

                                       10


Research and Development

     Our research and development efforts are focused on improving our
high-voltage device structures, wafer fabrication processes, analog circuit
designs and system level architecture. By these efforts, we seek to further
reduce the costs of our products, and improve the cost effectiveness and enhance
the functionality of our customers' power supplies. We have assembled a
multidisciplined team of highly skilled engineers to meet our research and
development goals. These engineers bring expertise in high-voltage structure and
process technology, analog design and power supply systems architecture.

     In 2000, 1999 and 1998, we spent $12.5 million, $10.8 million and $7.2
million, respectively, on research and development efforts. We expect to
continue to invest substantial funds in research and development activities. The
development of high-voltage analog ICs is highly complex. We cannot guarantee
that we will develop and introduce new products in a timely and cost-effective
manner or that our development efforts will successfully permit our products to
meet changing market demands.

Intellectual Property and Other Proprietary Rights

     We use a combination of patents, trademarks, copyrights, trade secrets and
confidentiality procedures to protect our intellectual property rights. We hold
29 U.S. patents and have generally filed for or received foreign patent
protection on these patents resulting in 56 foreign patents to date. The U.S.
patents have expiration dates ranging from 2006 to 2019. Eight of the U.S.
patents are related to the device structure of the high-voltage transistor, ten
are circuit patents that have been used in our products and three are circuit
patents that provide the foundation for our TOPSwitch products. Two of the U.S.
patents cover specific system applications using TOPSwitch. Additionally, we
have six new circuit patents, which we believe will provide a basis for our new
and future products. We are currently pursuing additional U.S. patent
applications relating to improvements and extensions of our products. We cannot
guarantee that our pending United States or foreign patent applications or any
future United States or foreign patent applications will be approved, that any
issued patents will protect our intellectual property or will not be challenged
by third parties, or that the patents of others will not have an adverse effect
on our ability to do business. Furthermore, we cannot guarantee that others will
not independently develop similar or competing technology or design around any
of our patents. We also hold 14 trademarks, five in the U.S., two in California,
two in Taiwan, one in Korea, one in Hong Kong and three in Japan.

     We regard as proprietary certain equipment, processes, information and
knowledge that we have developed and used in the design and manufacture of our
products. Our trade secrets include a proprietary high volume production process
that produces our patented high-voltage ICs. We attempt to protect our trade
secrets and other proprietary information through non-disclosure agreements,
proprietary information agreements with employees and consultants and other
security measures. Despite these efforts, we cannot guarantee that others will
not gain access to our trade secrets, or that we can meaningfully protect our
intellectual property. In addition, effective trade secret protection may be
unavailable or limited in certain foreign countries. Although we intend to
protect our rights vigorously, we cannot assure that such measures will be
completely successful.

     We have granted a perpetual non-transferable license to Matsushita to use
our semiconductor patents and other intellectual property for our current
high-voltage technology, including our TOPSwitch technology and improvements on
the existing technology, which allows Matsushita to manufacture and design
products for internal use and for sale or other distribution to Japanese
companies and to subsidiaries of Japanese companies in Asia. To the extent the
products they manufacture and design are not based on the TOPSwitch technology,
Matsushita may make sales or other distribution to Asian companies in Asia.
Matsushita has granted us perpetual cross licenses to the technology developed
by them under their license rights. We have agreed not to license the technology
licensed to Matsushita to other Japanese companies or their subsidiaries prior
to July 2005. In exchange for its license rights, Matsushita has paid and will
continue to pay to us licensing fees for a fixed period and has paid or will pay
royalties on products using the licensed technology during fixed periods.

     We have also granted a perpetual, non-transferable license to AT&T
Microelectronics to use certain of our IC processes and device technologies in
the products AT&T sells. In addition, pursuant to an agreement with

                                       11


MagneTek, Inc., we have granted MagneTek an exclusive, perpetual royalty-free
license to manufacture lighting products that incorporate certain of our
technology.

Manufacturing

     We contract with Matsushita and OKI to manufacture our wafers in foundries
located in Japan. Our semiconductor products are assembled and packaged by
independent subcontractors in China, Malaysia and the Philippines. We perform
testing, finishing and shipping at our facility in San Jose, California. This
fabless manufacturing model enables us to focus on our engineering and design
strengths, minimize fixed costs on capital expenditures, and still have access
to high-volume manufacturing capacity. Our products do not require leading edge
process geometries for them to be cost-effective, and thus we can use Matsushita
and OKI's older, low-cost facilities for wafer manufacturing. We use a
proprietary and sensitive implant process and must interact closely with
Matsushita and OKI to achieve satisfactory yields. Although we generally utilize
standard IC packages for assembly, some materials and aspects of assembly are
specific to our products. We require our manufacturers to use a high-voltage
molding compound that is difficult to process and is available from only one
supplier. This compound and its required processes, together with the other
non-standard materials and processes needed to assemble our products, require a
more exacting level of process control than normally required for standard
packages. As a result we must be involved with our contractors on an active
engineering basis to maintain and improve the process. We have developed process
monitoring equipment to support this effort and must provide adequate
engineering resources to provide similar support in the future.

     Our wafer supply agreements with Matsushita and OKI expire in June 2005 and
September 2003, respectively. Under the terms of our agreement with Matsushita,
we establish minimum annual and monthly purchase and sale commitments annually
with the mutual agreement of Matsushita. We also establish pricing by good faith
agreement, subject to our right to most favored pricing. Under the terms of the
OKI agreement, OKI has agreed to reserve a specified amount of production
capacity and to sell wafers to us at fixed prices. Our agreements with both
Matsushita and OKI provide for the purchase of wafers in Japanese yen.

     We cannot assure you that we will be able to reach an agreement with either
Matsushita or OKI to extend the term of their respective wafer supply
agreements. Failure to reach, in a timely fashion, an extension of either
agreement or to enter into a wafer supply arrangement with another manufacturer
could result in material disruptions in supply. Contractual provisions limit the
conditions under which we can enter into such arrangements with other Japanese
manufacturers or their subsidiaries during the term of the agreement with
Matsushita. In the event of a supply disruption with OKI or Matsushita, if we
were unable to quickly qualify alternative manufacturing sources for existing or
new products or if these sources were unable to produce wafers with acceptable
manufacturing yields, our operating results would suffer.

     We typically receive shipments from Matsushita or OKI approximately 8 to 10
weeks after placing orders, and lead times for new products can be substantially
longer. To provide sufficient time for assembly, testing and finishing, we
typically need to receive wafers from Matsushita and OKI 4 to 6 weeks before the
desired ship date to our customers. As a result of these factors and the fact
that customers' orders can be made with little advance notice, we have only a
limited ability to react to fluctuations in demand for our products. This could
cause us to have excess or a shortage of inventory of a particular product. From
time to time in the past we have been unable to fully satisfy customer requests
as a result of these factors. Any significant disruptions in deliveries would
materially adversely affect our business and operating results. We carry a
substantial amount of inventory of tested wafers to help offset these factors to
better serve our markets and meet customer demand.

Competition

     The high-voltage power supply industry is intensely competitive and
characterized by extreme price sensitivity. Accordingly, the most significant
competitive factor in the target markets for our products is cost effectiveness.
Our products face competition from alternative technologies, including
traditional linear transformers and discrete switcher power supplies. We believe
that at current pricing, our families of high-voltage power conversion ICs offer
favorable cost-performance benefits compared to linear and discrete switcher
supplies in many high-volume applications. However, there has been sizeable
overcapacity of discrete components, which

                                       12


resulted in significant price erosion for these products during 1999 and 2000. A
continuation of the price decline of discrete components, such as high-voltage
Bipolar and MOSFET transistors and PWM controller ICs, could adversely affect
the cost effectiveness of the TOPSwitch products. Also, older alternative
technologies like linear transformers are more cost-effective than discrete
switchers and integrated switchers that use our ICs in certain power ranges for
certain applications. If power requirements for certain applications in which
our products are currently utilized, such as battery chargers for cellular
telephones, drop below certain power levels, these older alternative
technologies can be used more cost effectively than switchers. Our TinySwitch IC
family, introduced in September 1998, was specifically designed to enhance the
cost effectiveness of our integrated switcher solutions in the low power range.
However, we cannot guarantee that our efforts in this area will be successful.

     Recently, our TOPSwitch product families have begun to meet increased
competition from hybrid and single high-voltage ICs similar to TOPSwitch. These
competing products are being developed or have been developed and are being
produced by companies such as ON Semiconductor, STMicroelectronics, Fairchild
Semiconductor and Sanken Electric Company. We expect competition to increase as
companies like these see the success we have had in converting older
technologies to the integrated solutions enabled by our product offerings. To
the extent these competitors' products are more cost effective than our
products, our business, financial condition and operating results could be
materially adversely affected. Many of our emerging competitors, including
Motorola, STMicroelectronics, Samsung and Sanken, have significantly greater
financial, technical, manufacturing and marketing resources than do we. In the
context of a market where a high-voltage IC is designed into a customer's
product and the provider of such ICs is therefore the sole source of the IC for
that product, greater manufacturing resources may be a significant factor in the
customer's choice of the IC because of the customer's perception of greater
certainty in its source of supply.

     Our ability to compete in our target markets also depends on such factors
as:

     .    timing and success of new product introductions by us and our
          competitors;

     .    the pace at which our customers incorporate our products into their
          end user products;

     .    availability of wafer fabrication and finished good manufacturing
          capability;

     .    availability of adequate sources of raw materials;

     .    protection of our products by effective utilization of intellectual
          property laws; and

     .    general economic conditions.

     We cannot assure you that our products will continue to compete favorably
or that we will be successful in the face of increasing competition from new
products and enhancements introduced by existing competitors or new companies
entering this market. Our failure to compete successfully in the high-voltage
power supply business would materially adversely affect our business, financial
condition and operating results.

Employees

     As of December 31, 2000, we employed 237 full time personnel, consisting of
94 in manufacturing, 58 in research and development, 30 in applications support,
30 in sales and marketing and 25 in finance and administration.

                                       13


Executive Officers of Power Integrations

     As of February 28, 2001, our executive officers, which are elected by and
serve at the discretion of the board of directors, were as follows:



Name                          Position With Power Integrations                                      Age
- --------------------------    ------------------------------------------------------------      --------
                                                                                          
Howard F. Earhart             Chairman of the Board, President and Chief Executive Officer          61
Balu Balakrishnan             Vice President, Engineering and Strategic Marketing                   46
Roderick D. Davies            Vice President, Operations                                            50
Joyce Engberg                 Vice President, Information Technology                                51
Richard S. Fassler            Vice President, Marketing                                             49
Robert J. Lelieur             Acting Vice President, Finance and Chief Financial Officer            58
Vladimir Rumennik             Vice President, Technology Development                                55
Daniel M. Selleck             Vice President, Worldwide Sales                                       54
Clifford J. Walker            Vice President, Corporate Development                                 49
Alan D. Bickell(1)(2)         Director                                                              64
Nicholas E. Brathwaite(2)     Director                                                              42
R. Scott Brown(1)             Director                                                              59
E. Floyd Kvamme(1)(2)         Director                                                              63
Steven J. Sharp               Director                                                              59


_________________

(1)  Member of the compensation committee

(2)  Member of the audit committee

     Howard F. Earhart has served as our president, chief executive officer and
as a director since January 1995. Mr. Earhart brings more than 30 years of
executive management experience to Power Integrations. His management experience
includes photographic film products at Eastman Kodak and consumer products at
Memorex Corporation where he was president of the Consumer Products Group. Mr.
Earhart also served as the CEO of Lin Data Corp. and Information Magnetics
Corporation; both companies manufacture semiconductor-based components for the
disk drive industry. He holds a B.S. in Chemical Engineering from Clarkson
University.

     Balu Balakrishnan has served as our vice president, engineering and
strategic marketing since September 1997. From September 1994 to September 1997,
Mr. Balakrishnan served as our vice president, engineering and marketing. Mr.
Balakrishnan served as our vice president, design engineering from April 1989 to
September 1994.

     Roderick D. Davies has served as our vice president, operations since
August 1999. In the previous eight years Mr. Davies held various positions,
including vice president of the business unit management, and marketing and
operations positions at International Rectifier, a worldwide supplier of power
semiconductors used for power conversion.

     Joyce Engberg has served as our vice president, information technology
since February 1999. From January 1996 to January 1999, Ms. Engberg served as
chief information officer of Spectrian, a manufacturer of RF power amplifiers.
From January 1993 to January 1996, Ms. Engberg served as director of technical
services of Consilium, a software company.

                                       14


     Richard S. Fassler has served as our vice president, marketing since
January 2000. From 1986 to 2000, Mr. Fassler held various positions, most
recently as the vice president of sales and marketing at IXYS Corporation, a
designer and developer of power semiconductors.

     Robert J. Lelieur has served as our acting vice president, finance and
chief financial officer since September 2000. From September 1997 to September
2000, Mr. Lelieur served as our director of finance. From July 1990 to September
1997, Mr. Lelieur held various senior level financial positions at Advanced
Computer Communications, a developer and manufacturer of inter-networking
software products, and National Insurance Group, a high-tech developer of risk
management services.

     Vladimir Rumennik has served as our vice president, technology development
since April 1991. From February 1990 to March 1991, Mr. Rumennik was our
director of technology development. Prior to January 1990, Mr. Rumennik was a
manager at Signetics, a semiconductor company and a subsidiary of Philips
Semiconductor.

     Daniel M. Selleck has served as our vice president, worldwide sales since
May 1993. From February 1984 to May 1993, Mr. Selleck held various sales
management positions with Philips Semiconductor including European regional
sales manager and western area sales manager in the United States.

     Clifford J. Walker has served as our vice president, corporate development
since June 1995. From September 1994 to June 1995, Mr. Walker served as vice
president of Reach Software, a software company. From December 1993 to September
1994, Mr. Walker served as president of Morgan Walker, a consulting company.

     Alan D. Bickell has served as a member of the board of directors since
April 1999. Mr. Bickell retired in 1996 after more than 30 years with Hewlett
Packard, serving as a corporate senior vice president and managing director of
geographic operations since 1992.

     Nicholas E. Brathwaite has served as a member of the board of directors
since January 2000. Mr. Brathwaite currently serves as senior vice president and
chief technology officer for Flextronics International, a provider of
engineering, advanced electronics manufacturing and logistical services, and has
held various engineering management positions with Flextronics since 1995. From
1989 to 1995, Mr. Brathwaite held various management positions at nChip, a
multi-chip module company.

     R. Scott Brown has served as member of the board of directors since July
1999. From 1985 to May 1999, Mr. Brown served as senior vice president of
worldwide sales and support for Xilinx, Inc., a designer and developer of
complete programmable logic solutions for use by electronic equipment
manufacturers.

     E. Floyd Kvamme has served as a member of the board of directors since
September 1989. Mr. Kvamme has been a general partner of Kleiner Perkins
Caufield & Byers, a venture capital company, since 1984. Mr. Kvamme also serves
on the boards of Brio Technology, Harmonic Inc., National Semiconductor, Photon
Dynamics and several private companies.

     Steven J. Sharp is one of our founders and has served as a member of the
board of directors since our inception. Mr. Sharp has served as president, chief
executive officer and chairman of the board of TriQuint Semiconductor, a
manufacturer of gallium arsenide integrated circuits, since September 1991.

                                       15


Item 2.   Properties.

     Our main executive, administrative, manufacturing and technical offices are
located in a 118,000 square foot facility in San Jose, California under a lease,
which expires in September 2010 with two conditional five-year options which if
exercised would extend the lease to September 2020.

Item 3.   Legal Proceedings.

     None.

Item 4.   Submission of Matters to a Vote of Security Holders.

     None.

                                       16


PART II

Item 5.  Market for Power Integration's Common Equity and Related Stockholder
         Matters.

     Our common stock trades on the Nasdaq National Market under the symbol
"POWI." As of February 28, 2001, there were approximately 132 stockholders of
record. Because brokers and other institutions on behalf of stockholders hold
many of such shares, we are unable to estimate the total number of stockholders
represented by these record holders. The following table sets forth, for the
quarter indicated, the range of daily closing prices per share of our common
stock as reported on the Nasdaq National Market:

                                                            Price Range
                                                       --------------------
           Year Ended December 31, 2000                  High        Low
           ----------------------------                --------    --------
           Fourth quarter                              $ 17.188    $  9.344
           Third quarter                               $ 26.125    $ 12.750
           Second quarter                              $ 30.750    $ 15.063
           First quarter                               $ 65.625    $ 22.750

           Year Ended December 31, 1999                  High        Low
           ----------------------------                --------    --------
           Fourth quarter                              $ 56.687    $ 34.875
           Third quarter                               $ 38.625    $ 25.968
           Second quarter                              $ 36.562    $ 14.218
           First quarter                               $ 17.187    $ 10.750

     All prices per share have been adjusted to reflect the 2-for-1 stock split
we effected on November 22, 1999.

     We have not paid any cash dividends on our capital stock. We currently
intend to retain our earnings for use in the operation and expansion of our
business and, therefore, do not anticipate paying any cash dividends in the
foreseeable future.

                                       17


Item 6.   Selected Financial Data.

     The following selected consolidated financial data should be read in
conjunction with "Management's Discussion and Analysis of Financial Condition
and Results of Operations" and the Consolidated Financial Statements and the
Notes thereto included elsewhere in this Form 10-K.



                                                                               Years Ended December 31,
                                                                ----------------------------------------------------
                                                                   2000        1999       1998      1997       1996
                                                                   ----        ----       ----      ----       ----
                                                                        (in thousands, except per share data)
                                                                                              
Consolidated Statements of Operations Data:
Net revenues:
     Product sales..........................................    $  109,759   $102,655    $68,206   $44,827  $  23,324
     License fees and royalties.............................         1,755      1,412      1,802     1,162        619
                                                                ----------   --------    -------   -------  ---------
          Total net revenues................................       111,514    104,067     70,008    45,989     23,943
Cost of revenues............................................        53,876     46,794     36,638    26,291     15,546
                                                                ----------   --------    -------   -------  ---------
Gross profit................................................        57,638     57,273     33,370    19,698      8,397
                                                                ----------   --------    -------   -------  ---------
Operating expenses:
     Research and development...............................        12,521     10,764      7,231     5,253      3,519
     Sales and marketing....................................        12,953     11,085      8,468     6,417      3,905
     General and administrative.............................         6,451      8,760      3,641     2,053      1,558
                                                                ----------   --------    -------   -------  ---------
          Total operating expenses..........................        31,925     30,609     19,340    13,723      8,982
                                                                ----------   --------    -------   -------  ---------
Income (loss) from operations...............................        25,713     26,664     14,030     5,975       (585)
Interest and other income (expense), net....................         2,523      2,147      1,248      (683)      (726)
                                                                ----------   --------    -------   -------  ---------
Income (loss) before provision for income taxes.............        28,236     28,811     15,278     5,292     (1,311)
Provision for income taxes..................................         8,471      4,334      2,600       530         30
                                                                ----------   --------    -------   -------  ---------
Net income (loss)...........................................    $   19,765   $ 24,477    $12,678   $ 4,762  $  (1,341)
                                                                ==========   ========    =======   =======  =========
Earnings (loss) per share:
     Basic..................................................    $     0.73   $   0.94    $  0.52   $  1.26  $   (0.78)
                                                                ==========   ========    =======   =======  =========
     Diluted................................................    $     0.69   $   0.87    $  0.48   $  0.25  $   (0.78)
                                                                ==========   ========    =======   =======  =========
Shares used in per share calculation:
     Basic..................................................        27,179     25,958     24,426     3,776      1,712
                                                                ==========   ========    =======   =======  =========
     Diluted................................................        28,774     28,197     26,452    18,678      1,712
                                                                ==========   ========    =======   =======  =========




                                                                                      December 31,
                                                                -------------------------------------------------------
                                                                   2000       1999       1998       1997      1996
                                                                   ----       ----       ----       ----      ----
                                                                                    (in thousands)
                                                                                               
Consolidated Balance Sheets Data:
Cash, cash equivalents and short-term investments...........      $ 63,434    $61,672    $44,418   $29,008    $ 7,692
Working capital.............................................      $ 87,005    $71,169    $42,988   $30,131    $ 9,769
Total assets................................................      $127,391    $98,571    $65,054   $48,559    $19,535
Long-term debt and capitalized lease obligations, net of
   current portion..........................................      $    715    $ 1,393    $ 1,963   $ 2,435    $ 5,499
Stockholders' equity........................................      $108,787    $80,248    $47,364   $33,327    $ 9,098


                                       18


Item 7.   Management's Discussion and Analysis of Financial Condition and
          Operating Results.

     This Management's Discussion and Analysis of Financial Condition and
Operating Results includes a number of forward-looking statements, which reflect
our current views with respect to future events and financial performance. These
forward-looking statements are subject to certain risks and uncertainties,
including those discussed in the "Risk Factors" and elsewhere in this report
that could cause actual results to differ materially from historical results or
those anticipated. In this report, the words "anticipates," "believes,"
"expects," "future," "intends," and similar expressions identify forward-looking
statements. We caution you not to place undue reliance on these forward-looking
statements, which speak only as of the date of this report.

Overview

     We design, develop, manufacture and market proprietary, high-voltage,
analog ICs for use in AC to DC power conversion primarily for the cellular
telephone, personal computer, cable and direct broadcast satellite and various
consumer electronics markets. From our inception in March 1988 through 1993, we
developed numerous standard and custom products incorporating high levels of
features and functionality, each intended to address the needs of various
markets. Although we succeeded in developing the core of our patented technology
during this period, market penetration of our products was low because these
products were not as cost-effective as alternative products. Limited product
revenue and the high costs associated with developing and marketing numerous
solutions to numerous target markets resulted in our being unprofitable.

     In 1993, we changed our strategy to focus on bringing cost-effective,
integrated products to the high-voltage AC to DC power supply markets. As a
result, in 1994, we completed development of TOPSwitch, the first in our family
of cost effective, high voltage, power conversion ICs. The TOPSwitch family of
products, with its proprietary integrated architecture, is designed to address
with relatively few products broad applications in a number of high-volume,
high-voltage AC to DC power supply markets. The initial target markets served by
TOPSwitch are particularly sensitive to size, portability, energy efficiency and
time-to-market. The TOPSwitch products and the solutions enabled by them are
significantly lower in cost than our previous products and the solutions enabled
by those products. Commercial shipments of TOPSwitch began in May 1994.
Primarily as a result of the increasing sales of TOPSwitch products, our net
revenues from product sales more than tripled between 1994 and 1995, increasing
from $5.0 million to $17.4 million. Net revenues from product sales increased
sequentially by 34% in 1996, 92% in 1997, 52% in 1998, 51% in 1999 and 7% in
2000.

     In response to increasing market acceptance of our TOPSwitch products and
faster revenue growth in 1996, we accelerated our investment in research and
development and sales and marketing, including technical customer support. As a
result, operating expenses were $9.0 million in 1996, $13.7 million in 1997,
$19.3 million in 1998, $30.6 million in 1999 and $31.9 million in 2000. We
expect our operating expenses to increase in absolute dollars, but to fluctuate
as a percentage of net revenues, as we continue to add resources to research and
development, sales and marketing and general and administrative activities.

     Our quarterly and annual operating results are volatile and difficult to
predict. Our net revenues and operating results have varied significantly in the
past, are difficult to forecast and are subject to numerous factors both within
and outside of our control. As a result, our quarterly and annual operating
results may fluctuate significantly in the future. For a discussion of the
factors that may affect our quarterly and annual operating results, please see
Factors that May Affect Future Results of Operations.

     We license certain technologies and grant limited product manufacturing and
marketing rights to strategic parties in return for foundry relationships,
license fees and product royalty arrangements. Prior to the introduction of
TOPSwitch in 1994, our analog ICs generated limited product sales while license
fees and prepaid royalties accounted for a significant percentage of our total
revenues. In future periods, we expect license fees and royalties to consist
primarily of royalties on products shipped by licensees incorporating licensed
technology, and anticipate that license fees and royalties will account for a
small percentage of net revenues.

     A portion of our cost of revenues consists of the cost of wafers. The
contract prices to purchase wafers from Matsushita and OKI are denominated in
Japanese yen. Changes in the exchange rate between the U.S. dollar and

                                       19


the Japanese yen subject our gross profit and operating results to the potential
for material fluctuations. From time to time, as these strategic parties close
old production lines and move to new fabrication facilities, we must absorb a
portion of the costs of physically moving the manufacturing of our products to
new production lines, including the costs of installation of new process
technologies.

     Product revenues consist of sales to OEMs and merchant power supply
manufacturers and to distributors. Revenues from product sales to OEMs and
merchant power supply manufacturers are recognized upon shipment. At that time,
we provide for estimated sales returns and other allowances related to those
sales. Between 40 and 50 percent of our sales are made to distributors under
terms allowing certain rights of return and price protection for our products
held in the distributors' inventories. Therefore, we defer recognition of
revenue and the proportionate cost of revenues derived from sales to
distributors until the distributors sell our products to their customers. The
gross profit deferred as a result of this policy is reflected as "deferred
income on sales to distributors" on our consolidated balance sheets. See Note 2
in the notes to consolidated financial statements.

Results of Operations

     The following table sets forth certain operating data as a percentage of
total net revenues for the periods indicated.



                                                                                       Percentage of
                                                                                    Total Net Revenues
                                                                             For the Years Ended December 31,
                                                                             --------------------------------
                                                                               2000        1999        1998
                                                                             --------    --------   ---------
                                                                                           
Net revenues:
     Product sales....................................................          98.4%       98.6%       97.4%
     License fees and royalties.......................................           1.6         1.4         2.6
                                                                             -------     -------     -------
          Total net revenues..........................................         100.0       100.0       100.0
Cost of revenues......................................................          48.3        45.0        52.3
                                                                             -------     -------     -------
Gross profit                                                                    51.7        55.0        47.7
                                                                             -------     -------     -------
Operating expenses:
     Research and development.........................................          11.2        10.3        10.3
     Sales and marketing..............................................          11.6        10.7        12.1
     General and administrative.......................................           5.8         8.4         5.2
                                                                             -------     -------     -------
          Total operating expenses....................................          28.6        29.4        27.6
                                                                             -------     -------     -------
Income from operations................................................          23.1        25.6        20.1
Interest and other income, net........................................           2.2         2.1         1.8
                                                                             -------     -------     -------
Income before provision for income taxes..............................          25.3        27.7        21.9
Provision for income taxes............................................           7.6         4.2         3.7
                                                                             -------     -------     -------
Net income   .........................................................          17.7%       23.5%       18.2%
                                                                             =======     =======     =======


Comparison of Years Ended December 31, 2000 and 1999

     Net revenues. Net revenues consist of revenues from product sales, which
are calculated net of returns and allowances, plus license fees and royalties
paid by licensees of our technology. Net revenues increased 7.2% to $111.5
million in 2000 compared to $104.1 million in 1999. Net revenues from product
sales represented $109.8 million and $102.7 million of net revenues in 2000 and
1999, respectively. The increase in net revenues from product sales was due
primarily from our "other" end market category in which no one market
represented more than 5% of our net revenues. Sales to the cellular phone
market, which is our largest end market, accounted for approximately 30% of our
net product revenues for 2000 compared to 39% of net product revenues in 1999.
Sales of our TOPSwitch and TinySwitch products represented 98% and 97% of net
revenues from product sales in 2000 and 1999, respectively. Net revenues from
royalties were $1.8 million in 2000 compared to $1.4 million in 1999. We expect
net revenues from royalties to continue to account for a small percentage of our
net revenues.

                                       20


     International sales were $93.7 million in 2000 compared to $81.6 million in
1999, representing approximately 84% and 78% of net revenues in those respective
periods. Although the power supplies using our products are designed and
distributed worldwide, most of these power supplies are manufactured in Asia. As
a result, the largest portion of our net revenues is derived from sales to this
region. We expect international sales to continue to account for a large portion
of our net revenues.

     In 2000, two separate customers, both of whom are distributors, accounted
for approximately 22% and 10% of net revenues. In 1999, the same customers
accounted for approximately 16% and 11% of net revenues, respectively. See Note
2 in the notes to consolidated financial statements.

     Cost of revenues; Gross profit. Gross profit is equal to net revenues less
cost of revenues. Our cost of revenues consists primarily of costs associated
with the purchase of wafers from Matsushita and OKI, the assembly and packaging
of our products, and internal labor and overhead associated with the testing of
both wafers and packaged components. These costs include expenses incurred in
connection with the physical move of the manufacturing of our products between
wafer production lines at our foundry suppliers and with the installation of new
process technologies at these foundries. These costs may recur from time to time
and adversely affect our cost of revenues.

     Gross profit was $57.6 million, or 51.7% of net revenues in 2000 compared
to $57.3 million, or 55.0% of net revenues, in 1999. We continued to see some
impact of increased pricing pressures to gross margins, and lost some
manufacturing efficiencies due to new product introductions. In 1999, gross
profit benefited from a one-time credit from one of our wafer suppliers in the
amount of $1.4 million, which improved our gross profit by 1.3% for that year.
We cannot assure you that our gross profit will remain at these levels in future
periods.

     Research and development expenses. Research and development expenses
consist primarily of employee-related expenses, and expensed material and
facility costs associated with the development of new processes and new
products. We also expense prototype wafers and mask sets related to new products
as research and development costs until new products are released to production.
Research and development expenses were $12.5 million, or 11.2% of net revenues
in 2000, compared to $10.8 million, or 10.3% of net revenues in 1999. The
increase in absolute dollars was primarily the result of increased salaries and
other costs related to the hiring of additional engineering personnel, outside
consulting fees and expensed prototype materials resulting from the transition
of foundry manufacturing processes, and bringing newly developed products into
manufacturing.

     Sales and marketing expenses. Sales and marketing expenses consist
primarily of employee-related expenses, commissions to sales representatives and
facilities expenses, including expenses associated with our regional sales and
support offices. Sales and marketing expenses were $13.0 million, or 11.6% of
net revenues in 2000, compared to $11.1 million, or 10.7% of net revenues in
1999. This increase in absolute dollars represented the addition of personnel to
support international sales and field application engineers.

     General and administrative expenses. General and administrative expenses
consist primarily of employee-related expenses for administration, finance,
human resources and general management, as well as consulting, outside services,
legal and auditing expenses. In 2000 and 1999, general and administrative
expenses were $6.5 million and $8.8 million, respectively, which represented
5.8% and 8.4% of net revenues in each respective period. The decrease in
absolute dollars in general and administrative expenses in 2000 was primarily
attributable to reduced professional and legal expenses related to the
settlement in 1999 of the patent infringement lawsuit that we filed.

     Interest and other income, net. Interest and other income, net, was $2.5
million and $2.1 million in 2000 and 1999, respectively. The increase in other
income reflected additional interest income related to the increase in cash
equivalents and short-term investments from 1999 to 2000, and lower interest
expense related to a reduction in our capital equipment lease obligations.

     Provision for income taxes. Provision for income taxes for 2000 and 1999
represents Federal, state and foreign taxes. The effective tax rate was 30% for
2000 and 15% for 1999. The increased tax rate in 2000 is primarily because the
impact of benefiting net operating loss carry-forwards ended in 1999. The
difference

                                       21


between the statutory rate of 35% and our effective tax rate for 2000 is due
primarily to the favorable effects of research and development tax credits,
foreign sales corporation and apportionment of state taxes, net of the federal
benefit. See Note 7 in the notes to consolidated financial statements.

Comparison of Years Ended December 31, 1999 and 1998

     Net revenues. Net revenues increased 48.7% to $104.1 million in 1999
compared to $70.0 million in 1998. Net revenues from product sales represented
$102.7 million and $68.2 million of net revenues in 1999 and 1998, respectively.
The increase in net revenues from product sales was due primarily to strong
demand for our products across all of our major markets and geographies. In
particular, sales to the cellular phone market accounted for approximately 39%
of our product revenues for 1999 compared to 26% of product revenues in 1998,
and increased 118% over 1998 sales into that market. Sales of our TOPSwitch and
TinySwitch products represented 97% and 95% of net revenues from product sales
in 1999 and 1998, respectively. Net revenues from royalties were $1.4 million in
1999 compared to $1.8 million in 1998.

     International sales were $81.6 million in 1999 compared to $58.1 million in
1998, representing approximately 78% and 83% of net revenues in those respective
periods. Although the power supplies using our products are designed and
distributed worldwide, most of these power supplies are manufactured in Asia. As
a result, the largest portion of our net revenues is derived from sales to this
region.

     In 1999, two separate customers accounted for approximately 16% and 11% of
net revenues. In 1998, the same customers accounted for approximately 22% and
13% of net revenues, respectively. See Note 2 in the notes to consolidated
financial statements.

     Cost of revenues; Gross profit. Gross profit was $57.3 million, or 55.0% of
net revenues in 1999 compared to $33.4 million, or 47.7% of net revenues in
1998. Efficiencies realized from higher volumes, reductions in wafer costs, and
improved test yields contributed to the improvement in gross profit. Gross
profit also benefited from a one-time credit from one of our wafer suppliers in
the amount of $1.4 million recorded in 1999. The credit improved our gross
profit by 1.3% for the year.

Research and development expenses. Research and development expenses were $10.8
million in 1999 compared to $7.2 million in 1998. The increase was primarily the
result of increased salaries and other costs related to the hiring of additional
engineering personnel, outside consulting fees and expensed prototype materials
resulting from the transition of foundry manufacturing processes, and bringing
newly developed products into manufacturing. These expenses remained unchanged
as a percentage of net revenues at 10.3% in both 1999 and 1998.

     Sales and marketing expenses. Sales and marketing expenses were $11.1
million, or 10.7% of net revenues in 1999, compared to $8.5 million, or 12.1% of
net revenues in 1998. This increase in absolute dollars represents the addition
of personnel to support international sales and field application engineers.

     General and administrative expenses. In 1999 and 1998, general and
administrative expenses were $8.8 million and $3.6 million, respectively, which
represented 8.4% and 5.2% of net revenues in each respective period. This
increase in general and administrative expenses was primarily attributable to
increased professional and legal expenses related to a patent infringement
lawsuit filed that we filed.

     Interest and other income, net. Interest and other income, net, was $2.1
million and $1.2 million in 1999 and 1998, respectively. The increase in other
income reflected additional interest income related to the increase in cash
equivalents and short-term investments from 1998 to 1999, and lower interest
expense related to a reduction in our capital equipment lease obligations.

     Provision for income taxes. Provision for income taxes for 1999 and 1998
represented Federal, state and foreign taxes. The effective tax rate was 15% for
1999 and 17% for 1998. The difference between the statutory rate and our
effective tax rate for 1999 and 1998 is due to the impact of benefiting net
operating loss carry-forwards, offset by the reduction in the deferred tax
valuation allowance. See Note 7 in the notes to consolidated financial
statements.

                                       22


Selected Quarterly Results of Operations

     The following tables set forth certain consolidated statements of
operations data for each of the quarters in the years ended December 31, 2000
and 1999 as well as the percentage of our net revenues represented by each item.
This information has been derived from our unaudited consolidated financial
statements. The unaudited consolidated financial statements have been prepared
on the same basis as the audited consolidated financial statements contained
herein and include all adjustments, consisting only of normal recurring
adjustments, that we consider necessary for a fair presentation of such
information when read in conjunction with our annual audited consolidated
financial statements and notes thereto appearing elsewhere in this report. The
operating results for any quarter are not necessarily indicative of the results
for any subsequent period or for the entire fiscal year.



                                                                 Three Months Ended
                                     ---------------------------------------------------------------------------
                                     Dec. 31, Sept. 30, June 30, Mar. 31,  Dec. 31, Sept. 30, June 30, Mar. 31,
                                       2000      2000     2000     2000      1999     1999      1999     1999
                                     -------- --------- -------- --------  -------- --------  -------- ---------
                                                                     (unaudited)
                                                        (in thousands, except per share data)
                                                                               
Net revenues:
  Product sales..................... $ 26,158  $ 27,377 $ 28,637 $ 27,587  $ 29,725 $ 29,829  $ 22,655 $ 20,446
  License fees and royalties........      474       483      375      423       402      311       324      375
                                     --------  -------- -------- --------  -------- --------  -------- --------
      Total net revenues............   26,632    27,860   29,012   28,010    30,127   30,140    22,979   20,821
Cost of revenues....................   13,287    13,280   13,867   13,442    14,178   12,667    10,482    9,467
                                     --------  -------- -------- --------  -------- --------  -------- --------
Gross profit........................   13,345    14,580   15,145   14,568    15,949   17,473    12,497   11,354
                                     --------  -------- -------- --------  -------- --------  -------- --------
Operating expenses:
  Research and development..........    2,951     3,084    3,431    3,055     3,080    2,813     2,535    2,336
  Sales and marketing...............    2,968     3,139    3,438    3,408     2,988    2,893     2,729    2,475
  General and administrative........    1,286     1,743    1,505    1,917     1,640    4,324     1,427    1,369
                                     --------  -------- -------- --------  -------- --------  -------- --------
      Total operating expenses......    7,205     7,966    8,374    8,380     7,708   10,030     6,691    6,180
                                     --------  -------- -------- --------  -------- --------  -------- --------
Income from operations..............    6,140     6,614    6,771    6,188     8,241    7,443     5,806    5,174
Interest and other income, net......      371       701      696      755       620      510       433      584
                                     --------  -------- -------- --------  -------- --------  -------- --------
Income before provision for
  income taxes......................    6,511     7,315    7,467    6,943     8,861    7,953     6,239    5,758
Provision for income taxes..........    1,930     2,219    2,240    2,082     1,346    1,185       939      864
                                     --------  -------- -------- --------  -------- --------  -------- --------
Net income.......................... $  4,581  $  5,096 $  5,227 $  4,861  $  7,515 $  6,768  $  5,300 $  4,894
                                     ========  ======== ======== ========  ======== ========  ======== ========
Earnings per share
  Basic ............................ $   0.17  $   0.19 $   0.19 $   0.18  $   0.28 $   0.26  $   0.21 $   0.19
  Diluted........................... $   0.16  $   0.18 $   0.18 $   0.17  $   0.26 $   0.24  $   0.19 $   0.18
Shares used in per share calculation
  Basic ............................   27,418    27,325   27,210   26,756    26,440   26,275    25,814   25,289
  Diluted...........................   28,101    28,495   28,702   28,877    28,916   28,589    28,183   27,425

                                                          Percentage of Total Net Revenues
                                     ---------------------------------------------------------------------------
                                     Dec. 31, Sept. 30, June 30, Mar. 31,  Dec. 31, Sept. 30, June 30, Mar. 31,
                                       2000      2000     2000     2000      1999     1999      1999     1999
                                     -------- --------- -------- --------  -------- --------  -------- ---------
                                                                               
Net revenues:
  Product sales.....................    98.2%     98.3%     98.7%    98.5%    98.7%     99.0%     98.6%    98.2%
  License fees and royalties........     1.8       1.7       1.3      1.5      1.3       1.0       1.4      1.8
                                     -------   -------  -------- --------  -------  --------  -------- --------
      Total net revenues............   100.0     100.0     100.0    100.0    100.0     100.0     100.0    100.0
Cost of revenues....................    49.9      47.7      47.8     48.0     47.1      42.0      45.6     45.5
                                     -------   -------  -------- --------  -------  --------  -------- --------
Gross profit........................    50.1      52.3      52.2     52.0     52.9      58.0      54.4     54.5
                                     -------   -------  -------- --------  -------  --------  -------- --------
Operating expenses:
  Research and development..........    11.1      11.1      11.8     10.9     10.2       9.4      11.0     11.2
  Sales and marketing...............    11.1      11.3      11.9     12.2      9.9       9.6      11.9     11.9
  General and administrative........     4.8       6.2       5.2      6.8      5.4      14.3       6.2      6.6
                                     -------   -------  -------- --------  -------  --------  -------- --------
      Total operating expenses......    27.0      28.6      28.9     29.9     25.5      33.3      29.1     29.7
                                     -------   -------  -------- --------  -------  --------  -------- --------
Income from operations..............    23.1      23.7      23.3     22.1     27.4      24.7      25.3     24.8
Interest and other income, net......     1.3       2.6       2.4      2.7      2.1       1.7       1.9      2.8
                                     -------   -------  -------- --------  -------  --------  -------- --------
Income before provision for income
  taxes.............................    24.4      26.3      25.7     24.8     29.5      26.4      27.2     27.6
Provision for income taxes..........     7.2       8.0       7.7      7.4      4.5       3.9       4.1      4.1
                                     -------   -------  -------- --------  -------  --------  -------- --------
Net income..........................    17.2%     18.3%     18.0%    17.4%    25.0%     22.5%     23.1%    23.5%
                                     =======   =======  ======== ========  =======  ========  ======== ========


                                       23


     Net revenues increased sequentially in the first three quarters of 1999 and
were essentially unchanged from the third quarter to the fourth quarter. Net
revenues decreased in the first quarter of 2000 from the fourth quarter of 1999
due to the seasonal nature of some of our markets, and then remained relatively
flat for the balance of 2000. We did not experience historical seasonal
increases in the third and fourth quarters of 2000, due primarily to weakening
of the cell phone market during that time.

     Our gross profit, as a percentage of net revenues, remained flat during the
first three quarters of 2000 and was down in the fourth quarter due primarily to
increased pricing pressures and some lost manufacturing efficiencies due to new
product introductions. The third quarter of 1999 benefited approximately 4% from
a one-time credit from one of our wafer suppliers.

     Research and development expenses, as a percentage of net revenues,
generally increased during the eight quarters presented, primarily due to
increased staffing in the areas of new product design and technology
development.

     Sales and marketing expenses generally increased in absolute dollars over
the first six quarters presented and then were down slightly in the third and
fourth quarter of 2000. The increases were due primarily to the additional
staffing in sales and application engineering and increased sales commissions
due to the increased revenues from product sales. Sales expenses were down in
the third and fourth quarters of 2000 due primarily to reduced commissions
because of lower net revenues.

     General and administrative expenses, as a percentage of net revenues,
remained relatively flat over the eight quarters presented except for a
significant increase in the third quarter of 1999 due primarily to increased
legal expenses related to a patent infringement lawsuit that we filed.

     Interest and other income, net, with the exception of the fourth quarter of
2000, essentially increased over the eight quarters presented primarily from
increased interest income due to higher cash balances created by a net positive
cash flow. Other income, net was down in the fourth quarter of 2000 due to a
one-time write off of abandoned leasehold improvements connected with the move
to our new facilities in that quarter.

Liquidity and Capital Resources

     Since our initial public offering of common stock in December 1997, our
principal source of funding has been cash from our operations with some funding
from capital equipment lease lines.

     As of December 31, 2000, we had approximately $63.4 million in cash, cash
equivalents and short-term investments. In addition, under a revolving line of
credit agreement with Union Bank of California, we can borrow up to $10.0
million. A portion of the credit line is used to cover advances for commercial
letters of credit and standby letters of credit, which we provide to Matsushita
and OKI prior to the shipment of wafers by those foundries to us. The balance of
this credit line is unused and available. The line of credit agreement contains
financial covenants and requires that we maintain profitability on a quarterly
basis and not pay or declare dividends without the bank's prior consent. We have
financed a significant portion of our machinery and equipment through capital
equipment leases. We financed additional equipment during the year ended
December 31, 1999 in the amount of $772,000 with no additional financing in the
year ended December 31, 2000. We may obtain additional financing for equipment
purchases in future quarters. As of December 31, 2000, we owed approximately
$1.4 million on our various capital equipment leases.

     As of December 31, 2000, we had working capital, defined as current assets
less current liabilities, of approximately $87 million, which was an increase of
approximately $15.9 over December 31, 1999. Our operating activities generated
cash of $14.2 million and $22.9 million in the year ended December 31, 2000 and
1999, respectively. Cash generated in the year ended December 31, 2000 was
principally the result of net income in the amount of $19.8 million,
depreciation and amortization and an increase in accrued liabilities. This was
partially offset by increases in deferred income taxes, inventory and prepaid
expenses. Cash generated in the year ended December 31, 1999 was principally the
result of net income of $24.5 million, depreciation and amortization

                                       24


and an increase in accrued liabilities, offset by increases in deferred income
taxes, accounts receivable and inventories.

     Our investing activities were a net transfer from short-term investments to
cash and cash equivalents of $6.8 million for the year ended December 31, 2000,
and a transfer from cash and cash equivalents to short-term investments of $13.5
million for the year ended December 31, 1999. We also purchased capital assets
in the amount of $16.2 million and $6.6 million for the years ended December 31,
2000 and 1999, respectively. The increase in purchases of capital assets in 2000
was primarily due to expenditures related to the purchase of tenant improvements
on our new facilities in San Jose.

     We believe that cash generated from operations, together with existing
sources of liquidity, will satisfy our projected working capital and other cash
requirements for at least the next 12 months.

New Accounting Standards

     In June 1999, the Financial Accounting Standards Board issued SFAS No. 137,
"Accounting for Derivative Instruments and Hedging Activities - Deferral of the
Effective Date of FASB Statement No. 133," which amends SFAS No. 133 to be
effective for all fiscal years beginning after June 15, 2000. In June 2000, SFAS
No. 133 was amended by SFAS No. 138, "Accounting for Certain Derivative
Instruments and Certain Hedging Activities", which amended or modified certain
issues discussed in SFAS No. 133. SFAS No. 138 is also effective for all fiscal
years beginning after June 15, 2000. SFAS No. 133 and SFAS No. 138 establish
accounting and reporting standards requiring that every derivative instrument be
recorded in the balance sheet as either an asset or liability measured at its
fair value. The statements also require that changes in the derivative's fair
value be recognized currently in earnings unless specific hedge accounting
criteria are met. The Company does not expect the adoption of SFAS No. 133 and
SFAS No. 138 to have a material impact on its financial statements.

     In December 1999, the Securities and Exchange Commission issued Staff
Accounting Bulletin No. 101 ("SAB 101"), "Revenue Recognition in Financial
Statements." SAB 101 provides guidance on applying generally accepted accounting
principles to revenue recognition issues in financial statements. We have
reviewed our revenue recognition policies and determined that we are in
compliance with SAB 101. Accordingly, there was no impact on our financial
statements from adopting SAB 101 in the fourth quarter of 2000.

Factors That May Affect Future Results of Operations

     In addition to the other information in this Report, the following factors
should be considered carefully in evaluating our business before purchasing
shares of our stock.

     Our quarterly and annual operating results are volatile and difficult to
predict. If we fail to meet the expectations of public market analysts or
investors, the market price of our common stock may decrease significantly. Our
net revenues and operating results have varied significantly in the past, are
difficult to forecast, are subject to numerous factors both within and outside
of our control, and may fluctuate significantly in the future. As a result, our
quarterly operating results will likely fall below the expectations of public
market analysts or investors. If that occurs, the price of our stock may
decline.

Some of the factors that could affect our operating results include the
following:

     .    the volume and timing of orders received from customers;

     .    the volume and timing of orders placed by us with our foundries;

     .    changes in product mix including the impact of new product
          introduction on existing products;

     .    our ability to develop and bring to market new products and
          technologies on a timely basis;

     .    the timing of investments in research and development and sales and
          marketing;

     .    cyclical semiconductor industry conditions; and

                                       25


        .    fluctuations in exchange rates, particularly the exchange rates
             between the U.S. dollar and the Japanese yen.

     Our quarterly results may be subject to seasonality. Historically, our
revenues are strongest in our third and fourth quarters, due to what we believe
are seasonal factors attributed to the high volume consumer markets for the end
products into which our ICs are sold. Our revenues have then followed a pattern
of being sequentially linear or somewhat down in the first and second quarters
of the next year.

     We do not have long-term contracts with any of our customers and if they
fail to place, or if they cancel or reschedule orders for our products, our
operating results and business may suffer. Our business is characterized by
short-term customer orders and shipment schedules. The ordering patterns of some
of our existing large customers have been unpredictable in the past and we
expect that customer-ordering patterns will continue to be unpredictable in the
future. Not only does the volume of units ordered by particular customers vary
substantially from period to period, but also purchase orders received from
particular customers often vary substantially from early oral estimates provided
by those customers for planning purposes. In addition, customer orders can be
canceled or rescheduled without significant penalty to the customer. In the past
we have experienced customer cancellations of substantial orders for reasons
beyond our control, and significant cancellations could occur again at any time.

     Intense competition in the high-voltage power supply industry may lead to a
decrease in the average selling price and reduced sales volume of our products,
which may harm our business. The high-voltage power supply industry is intensely
competitive and characterized by significant price erosion. Our products face
competition from alternative technologies, including traditional linear
transformers and discrete switcher power supplies. If the price of competing
products decreases significantly, the cost effectiveness of our products will be
adversely affected. If power requirements for applications in which our products
are currently utilized, including battery chargers for cellular telephones, drop
below current power levels, these older alternative technologies can be used
more cost effectively than our TOPSwitch-based switchers.

     We cannot assure you that our products will continue to compete favorably
or that we will be successful in the face of increasing competition from new
products and enhancements introduced by existing competitors or new companies
entering this market. We believe our failure to compete successfully in the
high-voltage power supply business, including our ability to introduce new
products with higher average selling prices, would materially harm our operating
results.

     If demand for our products declines in the cellular phone battery charger
and desktop personal computer stand-by markets, our net revenues will decrease.
Applications of our products in the cellular phone battery chargers and desktop
personal computer, or PC, stand-by markets have and will continue to account for
the majority of our net revenues. We expect that our net revenues and operating
results will continue to be substantially dependent upon these markets for the
foreseeable future. The cellular phone and desktop PC markets can be highly
cyclical and have been subject to significant economic downturns at various
times. Any significant downturn in these markets could cause our net revenues to
decline and the price of our stock to fall. In addition, technological advances
in these markets may reduce demand for our products.

     Because the sales cycle for our products can be lengthy, we may incur
substantial expenses before we generate significant revenues, if any. Our
products are generally incorporated into a customer's products at the design
stage. However, customer decisions to use our products, commonly referred to as
design wins, which can often require us to expend significant research and
development and sales and marketing resources without any assurance of success,
often precede volume sales, if any, by a year or more. The value of any design
win will largely depend upon the commercial success of the customer's product.
We cannot assure you that we will continue to achieve design wins or that any
design win will result in future revenues. If a customer decides at the design
stage not to incorporate our products into its product, we may not have another
opportunity for a design win with respect to that product for many months or
years.

     Our products must meet exacting specifications, and undetected defects and
failures may occur which may cause customers to return or stop buying our
products. Our customers generally establish demanding

                                       26


specifications for quality, performance and reliability that our products must
meet. ICs as complex as those we sell often encounter development delays and may
contain undetected defects or failures when first introduced or after
commencement of commercial shipments. We have from time to time in the past
experienced product quality, performance or reliability problems. If defects and
failures occur in our products, we could experience lost revenue, increased
costs, including warranty expense and costs associated with customer support,
delays in or cancellations or rescheduling of orders or shipments and product
returns or discounts, any of which would harm our operating results.

     We depend on third-party suppliers to provide us with wafers for our
products and if they fail to provide us sufficient wafers, our business will
suffer. We have supply arrangements for the production of wafers with Matsushita
and OKI. Although certain aspects of our relationships with Matsushita and OKI
are contractual, many important aspects of these relationships depend on their
continued cooperation and, in many instances, their course of conduct deviates
from the literal provisions of the contracts. We cannot assure you that we will
continue to work successfully with Matsushita or OKI in the future, that they
will continue to provide us with sufficient capacity at their foundries to meet
our needs, or that either of them will not seek an early termination of its
wafer supply agreement with us. We estimate that it would take 9 to 12 months
from the time we identified an alternate manufacturing source before that source
could produce wafers with acceptable manufacturing yields in sufficient
quantities to meet our needs.

     Although we provide Matsushita and OKI with rolling forecasts of our
production requirements, their ability to provide wafers to us is limited by the
available capacity of the foundry in which they manufacture wafers for us. An
increased need for capacity to meet internal demands or demands of other
customers could cause Matsushita and OKI to reduce capacity available to us.
Matsushita and OKI may also require us to pay amounts in excess of contracted or
anticipated amounts for wafer deliveries or require us to make other concessions
in order to acquire the wafer supply necessary to meet our customers'
requirements. Any of these concessions could harm our business.

     If our third-party suppliers and independent subcontractors do not produce
our wafers and assemble our finished products at acceptable yields, our net
revenues may decline. We depend on Matsushita and OKI to produce wafers, and
independent subcontractors to assemble finished products, at acceptable yields
and to deliver them to us in a timely manner. The failure of Matsushita or OKI
to supply us wafers at acceptable yields could prevent us from selling our
products to our customers and would likely cause a decline in our net revenues.
In addition, our IC assembly process requires our manufacturers to use a
high-voltage molding compound available from only one vendor, which is difficult
to process. This compound and its required processes, together with the other
non-standard materials and processes needed to assemble our products, require a
more exacting level of process control than normally required for standard
packages. Unavailability of the sole source compound or problems with the
assembly process can materially adversely affect yields and cost to manufacture.
We cannot assure you that acceptable yields will be maintainable in the future.

     Matsushita has licenses to our technology, which it may use to our
detriment. Our ability to take advantage of the potentially large Japanese
market for our products is largely dependent on Matsushita and its ability to
promote and deliver our products. Pursuant to our agreement with Matsushita,
Matsushita has the right to manufacture and sell products using our technology
to Japanese companies worldwide and to subsidiaries of Japanese companies
located in Asia. Although we receive royalties on Matsushita's sales, these
royalties are substantially lower than the gross profit we receive on direct
sales. We cannot assure you that Matsushita will not use the technology rights
we have granted it to develop or market competing products following any
termination of its relationship with us or after termination of Matsushita's
royalty obligation to us.

     Our international sales activities subject us to substantial risks. Sales
to customers outside of the United States account for a large portion of our net
revenues. These sales involve a number of risks to us, including:

        .   potential insolvency of international distributors and
            representatives;

        .   reduced protection for intellectual property rights in some
            countries;

                                       27


        .   the impact of recessionary environments in economies outside the
            United States;

        .   tariffs and other trade barriers and restrictions; and

        .   the burdens of complying with a variety of foreign laws.

     Our failure to adequately address these risks could reduce our
international sales, which would materially adversely affect our operating
results. Furthermore, because substantially all of our foreign sales are
denominated in U.S. dollars, increases in the value of the dollar increase the
price in local currencies of our products in foreign markets and make our
products relatively more expensive and less price competitive than competitors'
products that are priced in local currencies.

     If our efforts to enhance existing products and introduce new products are
not successful, we may not be able to generate demand for our products. Our
success depends in significant part upon our ability to develop new ICs for
high-voltage power conversion for existing and new markets, to introduce these
products in a timely manner and to have these products selected for design into
products of leading manufacturers. If we fail to develop and sell new products
in a timely manner, our net revenues could decline.

     We cannot be sure that we will be able to adjust to changing market demands
as quickly and cost-effectively as necessary to compete successfully.
Furthermore, we cannot assure you that we will be able to introduce new products
in a timely and cost-effective manner or in sufficient quantities to meet
customer demand or that these products will achieve market acceptance. Our or
our customers' failure to develop and introduce new products successfully and in
a timely manner would harm our business and may cause the price of our common
stock to fall. In addition, customers may defer or return orders for existing
products in response to the introduction of new products. Although we maintain
reserves against returns, we cannot assure you that these reserves will be
adequate.

     We Rely on a Continuous Power Supply to Conduct Operations, and
California's Current Energy Crisis Could Disrupt Our Business and Increase Our
Expenses. California is in the midst of an energy crisis that could disrupt our
operations and increase our expenses. In the event of an acute power shortage,
that is, when power reserves for California fall below 1.5%, California has on
some occasions implemented, and may in the future continue to implement, rolling
blackouts throughout California. Most of our operations are located in
California, although part of our inventory is stored and shipped from an
overseas facility. We currently have only limited backup generators for
emergency alternate sources of power in the event of a blackout. If blackouts
interrupt our power supply, we would be temporarily unable to continue
operations at our facilities. Any such interruption in our ability to continue
operations at our facilities could delay shipments of our products to customers,
and could result in lost revenue, which could harm our business and results of
operations.

     If our products do not penetrate additional markets, our business will not
grow as we predict. We believe that our future success depends in part upon our
ability to penetrate additional markets for our products. We cannot assure you
that we will be able to overcome the marketing or technological challenges
necessary to do so. To the extent that a competitor penetrates additional
markets before we do, or takes market share from us in our existing markets, our
net revenues and financial condition could be materially adversely affected.

     An Economic Downturn in the U.S. Could Cause a Decline in Demand for our
Products. The recent announcements of economic slowdown by major companies in
some of the end markets we serve, indirectly through our customers, may indicate
that there could be a slowdown in demand for some of our ICs. If our customers
are not successful in maintaining high levels of demand for their products,
their demand for our ICs may decrease and adversely affect our operating
results.

     If we are unable to adequately protect or enforce our intellectual property
rights, we could lose market share, incur costly litigation expenses or lose
valuable assets. Our success depends upon our ability to protect our
intellectual property, including patents, trade secrets, and know-how, and to
continue our technological innovation. We cannot assure you that the steps we
have taken to protect our intellectual property will be adequate to prevent
misappropriation or that others will not develop competitive technologies or
products. From time to

                                       28


time we have received, and we may receive in the future, communications alleging
possible infringement of patents or other intellectual property rights of
others. Litigation, which could result in substantial cost to us, may be
necessary to enforce our patents or other intellectual property rights or to
defend us against claimed infringement of the rights of others. The failure to
obtain necessary licenses or other rights or litigation arising out of
infringement claims could cause us to lose market share and harm our business.

     Moreover, the laws of some foreign countries in which our technology is or
may in the future be licensed may not protect our intellectual property rights
to the same extent as the laws of the United States, thus increasing the
possibility of infringement of our intellectual property.

     We must attract and retain qualified personnel to be successful and
competition for qualified personnel is intense in our market. Our success
depends to a significant extent upon the continued service of our executive
officers and other key management and technical personnel, and on our ability to
continue to attract, retain and motivate qualified personnel, such as
experienced systems applications engineers. The competition for these employees
is intense, particularly in Silicon Valley. The loss of the services of one or
more of our engineers, executive officers or other key personnel or our
inability to recruit replacements for these individuals or to otherwise attract,
retain and motivate qualified personnel could harm our business. We do not have
long-term employment contracts with, and we do not have in place key person life
insurance policies on, any of our employees.

     We have adopted anti-takeover measures, which may make it more difficult
for a third party to acquire us. Our board of directors has the authority to
issue up to 3,000,000 shares of preferred stock and to determine the price,
rights, preferences and privileges of those shares without any further vote or
action by the stockholders. The rights of the holders of common stock will be
subject to, and may be adversely affected by, the rights of the holders of any
preferred stock that may be issued in the future. The issuance of shares of
preferred stock, while potentially providing flexibility in connection with
possible acquisitions and for other corporate purposes, could have the effect of
making it more difficult for a third party to acquire a majority of our
outstanding voting stock. We have no present intention to issue shares of
preferred stock.

     In February 1999, our board of directors adopted a Preferred Stock Purchase
Rights Plan intended to guard against hostile takeover tactics. The adoption of
this plan was not in response to any proposal to acquire us, and the board is
not aware of any such effort. The existence of this plan could have the effect
of making it more difficult for a third party to acquire a majority of our
outstanding voting stock.

     The future trading price of our common stock could be subject to wide
fluctuations in response to a variety of factors. The price of our common stock
has been, and is likely to be, volatile. Factors including future announcements
concerning us or our competitors, quarterly variations in operating results,
announcements of technological innovations, the introduction of new products or
changes in our product pricing policies or those of our competitors, proprietary
rights or other litigation, changes in earnings estimates by analysts and other
factors could cause the market price of our common stock to fluctuate
substantially. In addition, stock prices for many technology companies fluctuate
widely for reasons, which may be unrelated to operating results. These
fluctuations, as well as general economic, market and political conditions, may
harm the market price of our common stock.

                                       29


Item 7A. Quantitative and Qualitative Disclosures About Market Risks

     Interest Rate Risk. Our exposure to market risk for changes in interest
rates relate primarily to our investment portfolio. We do not use derivative
financial instruments in our investment portfolio. We invest in high-credit
quality issuers and, by policy, limit the amount of credit exposure to any one
issuer. As stated in our policy, we ensure the safety and preservation of our
invested principal funds by limiting default risk, market risk and reinvestment
risk. We mitigate default risk by investing in safe and high-credit quality
securities and by constantly positioning our portfolio to respond appropriately
to a significant reduction in a credit rating of any investment issuer,
guarantor or depository. The portfolio includes only marketable securities with
active secondary or resale markets to ensure portfolio liquidity.

     The table below presents principal amounts and related weighted average
interest rates for our investment portfolio at December 31, 2000. All
investments mature, by policy, in 15 months or less.

(in thousands, except average interest rates)



                                                                                                     Weighted
                                                                                                     Average
                                                                                         Carrying    Interest
                                                                                          Amount       Rate
                                                                                         ---------   ---------
                                                                                               
Tax-exempt securities:

     Cash equivalents.................................................................    $ 25,950       4.67%

     Short-term investments...........................................................      25,949       3.78%
                                                                                         ---------
          Total investment securities.................................................    $ 51,899       4.22%
                                                                                         =========


     Foreign Currency Exchange Risk. We transact business in various foreign
countries. Our primary foreign currency cash flows are in Japan and Western
Europe. Currently, we do not employ a foreign currency hedge program utilizing
foreign currency forward exchange contracts as the foreign currency transactions
and risks to date have not been significant.

Item 8.  Consolidated Financial Statements and Supplementary Data.

     The Financial Statements and Supplementary Data required by this item are
set forth at the pages indicated at Item 14(a).

Item 9.  Changes in and Disagreements With Accountants on Accounting and
         Financial Disclosure.

     None.

                                       30


PART III

     The SEC allows us to include information required in this report by
referring to other documents or reports we have already or will soon be filing.
This is called "Incorporation by Reference." We intend to file our definitive
proxy statement pursuant to Regulation 14A not later than 120 days after the end
of the fiscal year covered by this report, and certain information therein is
incorporated in this report by reference.

Item 10.  Directors and Executive Officers of the Registrant.

     The information required by this Item is incorporated by reference to
information set forth in our definitive proxy statement under the heading
"Proposal No. 1--Election of Directors" and in Part I of this report under the
heading "Executive Officers of the Registrant."

     The information required by this Item with respect to compliance with
Section 16(a) of the Securities Exchange Act of 1934 is incorporated by
reference to information set forth in the definitive Proxy Statement under the
heading "Executive Compensation and Other Matters."

Item 11.  Executive Compensation.

     The information required by this Item is incorporated by reference to
information set forth in our definitive proxy statement under the heading
"Executive Compensation and Other Matters."

Item 12.  Security Ownership of Certain Beneficial Owners and Management.

     The information required by this Item is incorporated by reference to
information set forth in our definitive proxy statement under the heading "Stock
Ownership of Certain Beneficial Owners and Management."

Item 13.  Certain Relationships and Related Transactions.

     The information required by this Item is incorporated by reference to
information set forth in our definitive proxy statement under the heading
"Certain Relationships and Related Transactions."

                                       31


PART IV

Item 14.  Exhibits, Financial Statement Schedules and Reports on Form 8-K.

     (a) The following documents are filed as part of this Form:

         1. Financial Statements



                                                                                                             Page
                                                                                                             ----
                                                                                                          
               Report of Independent Public Accountants...................................................    33

               Consolidated Balance Sheets................................................................    34

               Consolidated Statements of Operations......................................................    35

               Consolidated Statements of Stockholders' Equity............................................    36

               Consolidated Statements of Cash Flows......................................................    37

               Notes to Consolidated Financial Statements.................................................    38


         2. Financial Statement Schedules

               All schedules, except Schedule II, Valuation and Qualifying
         Accounts, have been omitted because the required information is not
         present or not present in amounts sufficient to require submission of
         the schedules or because the information required is included in the
         Consolidated Financial Statements or Notes thereto.

         3. Exhibits

               See Index to Exhibits. The Exhibits listed in the accompanying
         Index to Exhibits are filed as part of this report.

     (b) Reports on Form 8-K

               None.

                                       32


                   REPORT OF INDEPENDENT PUBLIC ACCOUNTANTS

To Power Integrations, Inc.:

     We have audited the accompanying consolidated balance sheets of Power
Integrations, Inc. (a Delaware corporation) and subsidiaries as of December 31,
2000 and 1999, and the related consolidated statements of operations,
stockholders' equity and cash flows for each of the three years in the period
ended December 31, 2000. These financial statements and the schedule referred to
below are the responsibility of the Company's management. Our responsibility is
to express an opinion on these financial statements based on our audits.

     We conducted our audits in accordance with auditing standards generally
accepted in the United States. Those standards require that we plan and perform
the audit to obtain reasonable assurance about whether the financial statements
are free of material misstatement. An audit includes examining, on a test basis,
evidence supporting the amounts and disclosures in the financial statements. An
audit also includes assessing the accounting principles used and significant
estimates made by management, as well as evaluating the overall financial
statement presentation. We believe that our audits provide a reasonable basis
for our opinion.

     In our opinion, the financial statements referred to above present fairly,
in all material respects, the financial position of Power Integrations, Inc. and
subsidiaries as of December 31, 2000 and 1999, and the results of their
operations and their cash flows for each of the three years in the period ended
December 31, 2000, in conformity with accounting principles generally accepted
in the United States.

     Our audits were made for the purpose of forming an opinion on the basic
financial statements taken as a whole. The schedule listed under Item 14 (a) is
presented for purposes of complying with the Securities and Exchange
Commission's rules and is not a part of the basic financial statements. This
schedule has been subjected to the auditing procedures applied in our audits of
the basic financial statements and, in our opinion, fairly states in all
material respects the financial data required to be set forth therein in
relation to the basic financial statements taken as a whole.

                                                  ARTHUR ANDERSEN LLP

San Jose, California
January 19, 2001

                                       33


                           POWER INTEGRATIONS, INC.

                          CONSOLIDATED BALANCE SHEETS
                       AS OF DECEMBER 31, 2000 AND 1999

              (In thousands, except share and per share amounts)



                                                                                              2000         1999
                                                                                            --------     --------
                                                                                                   
                                         ASSETS
CURRENT ASSETS:
     Cash and cash equivalents..........................................................    $ 36,462     $ 27,883
     Short-term investments.............................................................      26,972       33,789
     Accounts receivable, net of allowances of $1,068 in 2000 and $990 in 1999..........       9,189        9,682
     Inventories........................................................................      21,599       11,406
     Deferred tax assets................................................................       6,054        3,918
     Prepaid expenses and other current assets..........................................       4,618        1,421
                                                                                            --------     --------
          Total current assets..........................................................     104,894       88,099
                                                                                            --------     --------

PROPERTY AND EQUIPMENT, AT COST:
     Machinery and equipment............................................................      28,832       21,632
     Leasehold improvements.............................................................       9,278        1,394
                                                                                            --------     --------
                                                                                              38,110       23,026
     Less: Accumulated depreciation and amortization....................................     (15,613)     (12,554)
                                                                                            --------     --------
                                                                                              22,497       10,472
                                                                                            --------     --------
                                                                                            $127,391     $ 98,571
                                                                                            ========     ========
                          LIABILITIES AND STOCKHOLDERS' EQUITY

CURRENT LIABILITIES:
     Current portion of capitalized lease obligations...................................    $    678     $  1,228
     Accounts payable...................................................................       7,490        6,524
     Accrued payroll and related expenses...............................................       2,980        3,994
     Taxes payable and other accrued liabilities........................................       4,175        1,818
     Deferred income on sales to distributors...........................................       2,566        3,366
                                                                                            --------     --------
          Total current liabilities.....................................................      17,889       16,930
                                                                                            --------     --------

CAPITALIZED LEASE OBLIGATIONS, net of current portion...................................         715        1,393
                                                                                            --------     --------

COMMITMENTS (NOTE 4)

STOCKHOLDERS' EQUITY:
     Common Stock, $0.001 par value
          Authorized-- 140,000,000 shares
          Outstanding--27,430,367 shares in 2000 and 26,468,272 shares in 1999..........          28           26
     Additional paid-in capital.........................................................      74,049       65,553
     Stockholder notes receivable.......................................................         (76)        (201)
     Deferred compensation..............................................................         (41)        (181)
     Cumulative translation adjustment..................................................        (118)        (129)
     Retained earnings..................................................................      34,945       15,180
                                                                                            --------     --------
          Total stockholders' equity....................................................     108,787       80,248
                                                                                            --------     --------
                                                                                            $127,391     $ 98,571
                                                                                            ========     ========


  The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                       34


                           POWER INTEGRATIONS, INC.

                     CONSOLIDATED STATEMENTS OF OPERATIONS
             FOR THE YEARS ENDED DECEMBER 31, 2000, 1999 AND 1998

                   (In thousands, except per share amounts)



                                                                                     2000          1999         1998
                                                                                   --------      --------     --------
                                                                                                     
NET REVENUES:
     Product sales.........................................................        $109,759      $102,655     $ 68,206
     License fees and royalties............................................           1,755         1,412        1,802
                                                                                   --------      --------     --------
         Total net revenues................................................         111,514       104,067       70,008

COST OF REVENUES...........................................................          53,876        46,794       36,638
                                                                                   --------      --------     --------

GROSS PROFIT...............................................................          57,638        57,273       33,370
                                                                                   --------      --------     --------
OPERATING EXPENSES:
     Research and development..............................................          12,521        10,764        7,231
     Sales and marketing...................................................          12,953        11,085        8,468
     General and administrative............................................           6,451         8,760        3,641
                                                                                   --------      --------     --------

         Total operating expenses..........................................          31,925        30,609       19,340
                                                                                   --------      --------     --------

INCOME FROM OPERATIONS.....................................................          25,713        26,664       14,030
                                                                                   --------      --------     --------
OTHER INCOME (EXPENSE):
     Interest income.......................................................           3,049         2,515        1,801
     Interest expense......................................................            (164)         (302)        (432)
     Other, net............................................................            (362)          (66)        (121)
                                                                                   --------      --------     ---------

         Total other income................................................           2,523         2,147        1,248
                                                                                   --------      --------     --------

INCOME BEFORE PROVISION FOR
    INCOME TAXES...........................................................          28,236        28,811       15,278

PROVISION FOR INCOME TAXES.................................................           8,471         4,334        2,600
                                                                                   --------      --------     --------

NET INCOME.................................................................        $ 19,765      $ 24,477     $ 12,678
                                                                                   ========      ========     ========

EARNINGS PER SHARE:
     Basic.................................................................        $   0.73      $   0.94     $   0.52
                                                                                   ========      ========     ========
     Diluted...............................................................        $   0.69      $   0.87     $   0.48
                                                                                   ========      ========     ========

SHARES USED IN PER SHARE CALCULATION:
     Basic.................................................................          27,179        25,958       24,426
                                                                                   ========      ========     ========
     Diluted...............................................................          28,774        28,197       26,452
                                                                                   ========      ========     ========


  The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                       35


                           POWER INTEGRATIONS, INC.

                CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY
             FOR THE YEARS ENDED DECEMBER 31, 2000, 1999 AND 1998

                                (In thousands)



                            Common Stock      Additional           Stockholder                 Cumulative   Retained      Total
                        --------------------   Paid-In                Notes        Deferred    Translation  Earnings   Stockholders'
                          Shares    Amount     Capital    Warrants  Receivable   Compensation  Adjustment   (Deficit)     Equity
                          ------    ------     -------    --------  ----------   ------------  ----------   ---------     ------
                                                                                            
BALANCE AT
  DECEMBER 31, 1997....   24,146    $   25     $ 56,207   $     12  $     (405)   $     (461)  $      (76)  $  (21,975)  $ 33,327
  Issuance of Common
     Stock under
      employee
     stock option
      plan, net of
      repurchases......      275        --          247         --          --            --           --           --        247
  Issuance of Common
     Stock under
      employee
     stock purchase
      plan.............      184        --          627         --          --            --           --           --        627
  Exercise of
      warrants, net....      389        --           46         --          --            --           --           --         46
  Proceeds of
      stockholder
     note repayment....       --        --           --         --         131            --           --           --        131
  Income tax benefit
      from
    employee stock
      option plan......       --        --          240         --          --            --           --           --        240
  Additional IPO
      costs............       --        --          (91)        --          --            --           --           --        (91)
  Amortization of
      deferred
    compensation.......       --        --           --         --          --           140           --           --        140
  Translation
      adjustment.......       --        --           --         --          --            --           19           --         19
  Net income...........       --        --           --         --          --            --           --       12,678     12,678
                        --------   -------     --------  ---------  ----------    ----------   ----------   ----------   --------
BALANCE AT
  DECEMBER 31, 1998....   24,994        25       57,276         12        (274)         (321)         (57)      (9,297)    47,364
  Issuance of Common
     Stock under
      employee
     stock option
      plan, net of
     repurchases.......      769         1        1,678         --          --            --           --           --      1,679
  Issuance of Common
     Stock under
       employee
     stock purchase
       plan............      351        --        1,267         --          --            --           --           --      1,267
  Exercise of
       warrants, net...      354        --           12        (12)         --            --           --           --         --
  Proceeds of
       stockholder
     note repayment....       --        --           --         --          73            --           --           --         73
  Income tax benefit
       from
     employee stock
       option plan.....       --        --        5,320         --          --            --           --           --      5,320
  Amortization of
       deferred
       compensation....       --        --           --         --          --           140           --           --        140
  Translation
       adjustment......       --        --           --         --          --            --          (72)          --        (72)
  Net income...........       --        --           --         --          --            --           --       24,477     24,477
                        --------   -------     --------  ---------  ----------    ----------   ----------   ----------   --------
BALANCE AT
  DECEMBER 31, 1999....   26,468        26       65,553         --        (201)         (181)        (129)      15,180     80,248
  Issuance of Common
     Stock under
      employee
     stock option
      plan, net of
     repurchases.......      704         2        2,919         --          --            --           --           --      2,921
  Issuance of Common
     Stock under
      employee
     stock purchase
      plan.............      258        --        1,942         --          --            --           --           --      1,942
  Proceeds of
      stockholder
     note repayment....       --        --           --         --         125            --           --           --        125
  Income tax benefit
      from
     employee stock
      option plan......       --        --        3,635         --          --            --           --           --      3,635
  Amortization of
      deferred
     compensation......       --        --           --         --          --           140           --           --        140
  Translation
      adjustment.......       --        --           --         --          --            --           11           --         11
  Net income...........       --        --           --         --          --            --           --       19,765     19,765
                        --------   -------     --------  ---------  ----------    ----------   ----------   ----------   --------
BALANCE AT
  DECEMBER 31, 2000....   27,430   $    28     $ 74,049  $      --   $     (76)   $      (41)   $    (118)  $   34,945   $108,787
                        ========   =======     ========  =========   =========    ==========    =========   ==========   ========



   The accompanying notes are an integral part of these consolidated financial
statements.


                                       36


                           POWER INTEGRATIONS, INC.

                     CONSOLIDATED STATEMENTS OF CASH FLOWS
             FOR THE YEARS ENDED DECEMBER 31, 2000, 1999 AND 1998

                                (In thousands)



                                                                                      2000         1999        1998
                                                                                      ----         ----        ----
                                                                                                     
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income                                                                          $ 19,765     $ 24,477     $ 12,678
Adjustments to reconcile net income to net cash provided by
   operating activities:
     Depreciation and amortization..............................................       4,189        3,231        3,034
     Deferred compensation expense..............................................         140          140          140
     Deferred income taxes......................................................      (2,136)      (3,918)         240
     Provision for (reduction in) accounts receivable and other allowances......       1,084          129          838
     Change in operating assets and liabilities:
          Accounts receivable...................................................        (591)      (5,170)         765
          Inventories...........................................................     (10,193)      (2,561)      (1,517)
          Prepaid expenses and other current assets.............................      (3,197)        (610)        (463)
          Accounts payable......................................................         966          656       (1,036)
          Accrued liabilities...................................................       4,989        5,716        2,637
          Deferred income on sales to distributors..............................        (800)         800        1,186
                                                                                    --------     --------     --------
               Net cash provided by operating activities........................      14,216       22,890       18,502
                                                                                    --------     --------     --------
CASH FLOWS FROM INVESTING ACTIVITIES:
     Purchases of property and equipment........................................     (16,214)      (6,592)      (1,956)
     Purchases of short-term investments........................................     (31,349)     (52,070)     (47,904)
     Proceeds from sales and maturities of short-term investments...............      38,166       38,524       31,117
                                                                                    --------     --------     --------

               Net cash used in investing activities............................      (9,397)     (20,138)     (18,743)
                                                                                    --------     --------     --------
CASH FLOWS FROM FINANCING ACTIVITIES:
     Net proceeds from issuance of common stock.................................       4,863        2,946          828
     Proceeds from stockholder note repayment...................................         125           73          131
     Principal payments under capitalized lease obligations.....................      (1,228)      (2,064)      (2,095)
                                                                                    --------     --------     --------
               Net cash provided by (used in) financing activities..............       3,760          955       (1,136)
                                                                                    --------     --------     --------
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS............................       8,579        3,707       (1,377)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD................................      27,883       24,176       25,553
                                                                                    --------     --------     --------
CASH AND CASH EQUIVALENTS AT END OF PERIOD......................................    $ 36,462     $ 27,883     $ 24,176
                                                                                    ========     ========     ========
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:
     Capitalized lease obligations incurred for property and equipment..........    $     --     $    772     $  1,786
                                                                                    ========     ========     ========
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
     Cash paid for interest.....................................................    $    161     $    312     $    445
                                                                                    ========     ========     ========
     Cash paid for income taxes.................................................    $  4,756     $  3,208     $    714
                                                                                    ========     ========     ========


  The accompanying notes are an integral part of these consolidated financial
                                  statements.

                                       37


                           POWER INTEGRATIONS, INC.

                  NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

                               DECEMBER 31, 2000

1.   THE COMPANY:

     Power Integrations, Inc. (the "Company"), which was incorporated in
California on March 25, 1988 and reincorporated in Delaware in December 1997
(see Note 6), designs, develops, manufactures and markets proprietary, high-
voltage, analog integrated circuits for use in AC to DC power conversion
primarily for the cellular telephone, personal computer, cable and direct
broadcast satellite decoder box market and various consumer and industrial
electronics markets.

     The Company is subject to a number of risks including, among others, the
volume and timing of orders received by the Company from its customers;
competitive pressures on selling prices; the volume and timing of orders placed
by the Company with its foundries; the availability of raw materials;
fluctuations in manufacturing yields, whether resulting from the transition to
new foundries or from other factors; changes in product mix, including the
impact of new product introductions on existing products; the Company's ability
to develop and bring to market new products and technologies on a timely basis;
the introduction of products and technologies by the Company's competitors;
market acceptance of the Company's and its customers' products; the timing of
investments in research and development and sales and marketing; cyclical
semiconductor industry conditions; fluctuations in exchange rates, particularly
exchange rates between the U.S. dollar and the Japanese yen; and changes in the
international business climate and economic conditions.

     All of the wafers used by the Company are manufactured by two offshore
independent foundries. Although there are a number of other suppliers that could
provide similar services, a change in suppliers could cause a delay in
manufacturing and possible loss of sales, which could adversely affect operating
results.

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES:

   Principles of Consolidation and Foreign Currency Translation

     The consolidated financial statements include the accounts of the Company
and its wholly owned subsidiaries after elimination of intercompany transactions
and balances. The functional currencies of the Company's subsidiaries are the
local currencies. Accordingly, all assets and liabilities are translated into
U.S. dollars at the current exchange rates as of the applicable balance sheet
date. Revenues and expenses are translated at the average exchange rate
prevailing during the period. Cumulative gains and losses from the translation
of the foreign subsidiaries' financial statements have been included in
stockholders' equity.

   Reclassifications

     Certain prior year's balances have been reclassified to conform to the
current year's presentation.

   Cash and Cash Equivalents and Short-Term Investments

     The Company considers cash invested in highly liquid financial instruments
with an original maturity of three months or less to be cash equivalents. Cash
investments in highly liquid financial instruments with original maturities
greater than three months but not longer than fifteen months are classified as
short-term investments. As of December 31, 2000 and 1999, the Company's short-
term investments consist of U.S. government backed securities, corporate
commercial paper and other high quality commercial and municipal securities,
which were classified as held-to-maturity and were valued using the amortized
cost method which approximates market.

                                       38


                           POWER INTEGRATIONS, INC.

            NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(Continued)


   The table below summarizes the value of the Company's investments by major
security type (in thousands):



                                                                                                December 31,
                                                                                           --------------------
                                                                                             2000        1999
                                                                                           --------    --------
                                                                                                 
Cash Equivalents:
     U.S. corporate securities.........................................................     $    --     $ 5,488
     Tax-exempt securities.............................................................      25,950      20,500
                                                                                            -------     -------

          Total cash equivalents.......................................................      25,950      25,988
                                                                                            -------     -------
Short-term Investments:
     U.S. corporate securities.........................................................     $    --      17,897
     Foreign securities................................................................          --       3,079
     Tax-exempt securities.............................................................      25,949      11,999
                                                                                            -------     -------

          Total short-term investments.................................................      25,949      32,975
                                                                                            -------     -------

          Total investment securities..................................................     $51,899     $58,963
                                                                                            =======     =======


Inventories

         Inventories (which consist of costs associated with the purchases of
wafers from offshore foundries and of packaged components from several offshore
assembly manufacturers, as well as internal labor and overhead associated with
the testing of both wafers and packaged components) are stated at the lower of
cost (first in, first-out) or market. Provisions, when required, are made to
reduce excess and obsolete inventories to their estimated net realizable values.
Inventories consist of the following (in thousands):



                                                                                     December 31,
                                                                                 ---------------------
                                                                                   2000        1999
                                                                                 ---------   ---------
                                                                                       
          Raw materials....................................................      $   1,520   $   4,039
          Work-in-process..................................................         13,409       4,059
          Finished goods...................................................          6,670       3,308
                                                                                 ---------   ---------
                                                                                 $  21,599   $  11,406
                                                                                 =========   =========


   Property and Equipment

     Depreciation and amortization of property and equipment are provided using
the straight-line method over the shorter of the estimated useful lives of the
assets (over a period of one to four years), or over the applicable lease term.

     Included in property and equipment are assets acquired under capital lease
obligations with an original cost of approximately $4.4 million and $8.0
million, as of December 31, 2000 and 1999, respectively. Related accumulated
amortization on these leased assets was approximately $3.3 million and $5.7
million, as of December 31, 2000 and 1999, respectively.

                                       39


                           POWER INTEGRATIONS, INC.

            NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(Continued)


   Earnings Per Share

     Earnings per share are calculated in accordance with Statement of Financial
Accounting Standards (SFAS) No. 128 "Earnings per Share." SFAS No. 128 requires
companies to compute earnings per share under two different methods (basic and
diluted). Basic earnings per share are calculated by dividing net income by the
weighted average shares of common stock outstanding during the period. Diluted
earnings per share are calculated by dividing net income by the weighted average
shares of outstanding common stock and common stock equivalents during the
period. Common stock equivalents included in the diluted calculation consist of
dilutive shares issuable upon the exercise of outstanding common stock options
and warrants computed using the treasury stock method.

     A summary of the earnings per share calculation is as follows (in
thousands, except per share amounts):



                                                                                                    December 31,
                                                                                         ---------------------------------
                                                                                             2000        1999       1998
                                                                                             ----        ----       ----
                                                                                                         
Basic earnings per share:
     Net income........................................................................      $19,765    $24,477    $12,678
                                                                                             =======    =======    =======
     Weighted average common shares....................................................       27,179     25,958     24,426
                                                                                             =======    =======    =======
          Basic earnings per share.....................................................      $  0.73    $  0.94    $  0.52
                                                                                             =======    =======    =======
Diluted earnings per share:
     Net income........................................................................      $19,765    $24,477    $12,678
                                                                                             =======    =======    =======

     Weighted average common shares....................................................       27,179     25,958     24,426
     Weighted average common share equivalents:
          Options......................................................................        1,569     2,170       1,446
          Employee stock purchase plan.................................................           26        69          10
          Warrants.....................................................................           --        --         570
                                                                                             -------    -------    -------
     Diluted weighted average common shares............................................       28,774     28,197     26,452
                                                                                             =======    =======    =======
          Diluted earnings per share...................................................      $  0.69    $  0.87    $  0.48
                                                                                             =======    =======    =======


   Comprehensive Income

          SFAS No. 130, "Reporting Comprehensive Income," establishes standards
for reporting and the presentation of comprehensive income and its components.
SFAS No. 130, which was adopted by the Company in the first quarter of 1998,
requires companies to report a new measurement of income to include unrealized
gains and losses, net of the tax effect that have historically been excluded
from net income and reflected instead in stockholders' equity. Comprehensive
income for the Company consists of net income plus the effect of foreign
currency translation adjustments, which is not material for each of the three
years ended December 31, 2000. Accordingly, comprehensive income closely
approximates actual net income.

   Segment Reporting

      During 1998, the Company adopted SFAS No. 131, "Disclosures About Segments
of an Enterprise and Related Information." SFAS No. 131 requires a new basis of
determining reportable business segments, i.e., the management approach. This
approach requires that business segment information used by management to assess
performance and manage company resources be the source for information
disclosure. On this basis, the Company is organized and operates as one business
segment, the design, development, manufacture and marketing of proprietary,
high-voltage, analog integrated circuits for use primarily in the AC to DC power
conversion markets.

                                       40


                            POWER INTEGRATIONS, INC.

            NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(Continued)

   New Accounting Standards

     In June 1999, the Financial Accounting Standards Board issued SFAS No. 137,
"Accounting for Derivative Instruments and Hedging Activities - Deferral of the
Effective Date of FASB Statement No. 133," which amends SFAS No. 133 to be
effective for all fiscal years beginning after June 15, 2000. In June 2000, SFAS
No. 133 was amended by SFAS No. 138, "Accounting for Certain Derivative
Instruments and Certain Hedging Activities", which amended or modified certain
issues discussed in SFAS No. 133. SFAS No. 138 is also effective for all fiscal
years beginning after June 15, 2000. SFAS No. 133 and SFAS No. 138 establish
accounting and reporting standards requiring that every derivative instrument be
recorded in the balance sheet as either an asset or liability measured at its
fair value. The statements also require that changes in the derivative's fair
value be recognized currently in earnings unless specific hedge accounting
criteria are met. The Company does not expect the adoption of SFAS No. 133 and
SFAS No. 138 to have a material impact on its financial statements.

   Revenue Recognition, Significant Customers

     In December 1999, the Securities and Exchange Commission issued Staff
Accounting Bulletin No. 101 ("SAB 101"), "Revenue Recognition in Financial
Statements." SAB 101 provides guidance on applying generally accepted accounting
principles to revenue recognition issues in financial statements. The Company
has reviewed its revenue recognition policies and determined that they are in
compliance with SAB 101. Accordingly, there was no impact on the Company's
financial statements from adopting SAB 101 in the fourth quarter of 2000.

     Product revenues consist of sales to OEMs and merchant power supply
manufacturers and to distributors. Revenues from product sales to OEM and
merchant power supply manufacturers are recognized upon shipment. The Company
provides for estimated sales returns and allowances related to such sales at the
time of shipment. During 2000, 1999 and 1998, sales to distributors of the
Company's products accounted for approximately 50%, 40% and 48% of net revenues,
respectively. Sales to distributors are made under terms allowing certain rights
of return and protection against subsequent price declines of the Company's
products held by the distributors. Pursuant to the Company's distributor
agreements, the Company protects its distributors' exposure related to the
impact of price reductions as well as products at distributors that are slow
moving or have been discontinued. These agreements, which may be canceled by
either party on a specified notice, generally contain a provision for the return
of the Company's product in the event the agreement with the distributor is
terminated. Accordingly, the Company defers recognition of revenue and the
proportionate costs of revenues derived from sales to distributors until such
distributors resell the Company's products to their customers. The margin
deferred as a result of this policy is reflected as "deferred income on sales to
distributors" in the accompanying consolidated balance sheets.

     The Company has entered into a separate wafer supply and technology license
agreement with an unaffiliated wafer foundry. The wafer supply agreement, which
expires in June 2005, is renewable. In connection with the technology license
agreement, the Company is entitled to receive a royalty on sales of products by
the foundry, which incorporates the Company's technology into its own products.
For the years ended December 31, 2000, 1999 and 1998, revenue recognized under
this agreement was approximately $1.7 million, $1.4 million and $1.8 million,
respectively.

                                       41


                           POWER INTEGRATIONS, INC.

            NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(Continued)


     The Company's end user base is highly concentrated and a relatively small
number of OEMs, directly or indirectly through merchant power supply
manufacturers, accounted for a significant portion of the Company's revenue. For
the years ended December 31, 2000, 1999 and 1998, ten customers accounted for
approximately 69%, 68% and 67% of net revenues, respectively.

     The following customers accounted for more than 10% of total net revenues:



                                                                        Year Ended December 31,
                                                                   -----------------------------------
                   Customer                                          2000         1999        1998
                   --------                                        ----------   ----------  ----------
                                                                                   
                   A...........................................        22%          16%         22%
                   B...........................................        10%          11%         13%


   Export Sales

     The Company markets its products in North America and in foreign countries
through its sales personnel and a worldwide network of independent sales
representatives and distributors. Export sales, which consist of domestic sales
to customers in foreign countries are comprised of the following:



                                                                        Year Ended December 31,
                                                                    --------------------------------
                                                                      2000        1999        1998
                                                                    --------    --------    --------
                                                                                   
                   Taiwan                                                 25%         19%         26%
                   Hong Kong/China................................        24%         20%         26%
                   Western Europe.................................        17%         16%         15%
                   Korea..........................................        10%         13%          7%
                   Japan..........................................         2%          2%          3%
                   Other..........................................         6%          8%          6%
                                                                    --------    --------    --------
                        Total export sales........................        84%         78%         83%
                                                                    ========    ========    ========


   Product Sales

     Sales of TOPSwitch products accounted for 98%, 97% and 95% of total net
revenues in 2000, 1999 and 1998, respectively. TOPSwitch products include
TOPSwitch, TOPSwitch II, TOPSwitch-FX, TOPSwitch-GX and TinySwitch.

   Foreign Currency Risk

     The Company maintains a Japanese yen bank account with a U.S. bank for
payments to suppliers and for cash receipts from Japanese suppliers and
customers denominated in yen. For the year ended December 31, 2000 the Company's
realized gains and losses on foreign exchange transactions netted to zero. For
the years ended December 31, 1999 and 1998, the Company realized foreign
exchange transaction gains of approximately $123,000 and $35,000, respectively.
These amounts are included in "other income (expense)," in the accompanying
consolidated statements of operations.

   Estimates

     The preparation of financial statements in conformity with accounting
principles generally accepted in the United States requires management to make
estimates and assumptions that affect the reported amounts of assets and
liabilities and disclosures of contingent assets and liabilities at the date of
the financial statements and the reported amounts of revenues and expenses
during the reporting period. Actual results could differ from those estimates.

                                       42


                           POWER INTEGRATIONS, INC.

            NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(Continued)

   Concentration of Credit Risk

     Financial instruments that potentially subject the Company to
concentrations of credit risk consist principally of cash investments and trade
receivables. The Company has cash investment policies that limit cash
investments to short-term, low risk investments. With respect to trade
receivables, the Company performs ongoing credit evaluations of its customers'
financial condition and requires letters of credit whenever deemed necessary.
Additionally, the Company establishes an allowance for doubtful accounts based
upon factors surrounding the credit risk of specific customers, historical
trends related to past losses and other relevant information. As of December 31,
2000 and 1999, approximately 78% and 73% of accounts receivable, respectively,
were concentrated with ten customers.

3. BANK LINE OF CREDIT:

     The Company entered into a $10.0 million revolving line of credit agreement
with a bank in October 1998. Advances under the agreement bear interest at a
fixed rate of the bank's LIBOR rate plus 1.5% per annum or at the bank's
variable interest rate. The Company has the option to choose between the two
rates. As of December 31, 2000 and 1999, there were no amounts due under the
bank line of credit. The agreement also covers advances for commercial letters
of credit and standby letters of credit, used primarily for the shipment of
wafers from wafer supply manufacturers to the Company, provided that at no time
will the aggregate sum of all advances exceed $10.0 million. As of December 31,
2000, there were outstanding letters of credit totaling approximately $3.4
million, and as of December 31, 1999, there were outstanding letters of credit
totaling 96,587,000 Japanese yen (approximately $964,000). The agreement, which
expires on July 1, 2002, restricts the Company from entering into certain
transactions and contains certain financial covenants.

4. COMMITMENTS:

     The Company leases its facilities under noncancellable operating leases,
which expire at various dates through October 2010. The lease for the Company's
main corporate facility in San Jose, California expires in September 2010 and
contains two conditional five-year options, which if exercised would extend the
lease to September 2020. Rent expense under all operating leases was
approximately $2.1 million, $1.1 million and $500,000 in 2000, 1999 and 1998,
respectively. Under the terms of the lease for the San Jose corporate facility,
the Company is entitled to receive reimbursement of tenant improvements from the
landlord in the amount of approximately $3.0 million, which is included in
prepaid expenses and other current assets as of December 31, 2000 in the
accompanying consolidated balance sheets.

     A significant portion of the Company's machinery and equipment is leased
under agreements accounted for as capital leases. The Company had no new lease
financing during 2000 and leased approximately $772,000 and $1,786 million of
equipment during 1999 and 1998, respectively, under capital leasing
arrangements. In 1998, the Company entered into a capital lease line of credit
agreement, which allowed for combined borrowings of up to $4.4 million to
finance the acquisition of property and equipment. This agreement expired on
June 30, 1999.

                                       43


                           POWER INTEGRATIONS, INC.

            NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(Continued)

     Future minimum lease payments under all noncancellable operating and
capital lease agreements as of December 31, 2000 are as follows (in thousands):



     Fiscal Year                                                                      Operating   Capital
     ----------                                                                       ---------   -------
                                                                                           
     2001                                                                             $   1,858  $    747
     2002                                                                                 1,932       463
     2003                                                                                 2,009       241
     2004                                                                                 2,090        42
     2005                                                                                 2,173        --
     Thereafter                                                                          11,450        --
                                                                                      ---------  --------

     Total minimum lease payments....................................................  $ 21,512     1,493
                                                                                       ========
     Less: Amounts representing interest on capital leases (4.4% to 12.0%)...........                (100)
                                                                                                 --------
                                                                                                    1,393
     Less: Current portion...........................................................                (678)
                                                                                                 --------
     Long-term portion...............................................................            $    715
                                                                                                 ========


5. PREFERRED STOCK PURCHASE RIGHTS PLAN:

     In February 1999, the Company adopted a Preferred Stock Purchase Rights
Plan (the "Plan") designed to enable all stockholders to realize the full value
of their investment and to provide for fair and equal treatment for all
stockholders in the event that an unsolicited attempt is made to acquire the
Company. Under the Plan, stockholders received one right to purchase one
one-thousandth of a share of a new series of preferred stock for each
outstanding share of common stock held of record at the close of business on
March 12, 1999 at $150.00 per right, when someone acquires 15 percent or more of
the Company's common stock or announces a tender offer which could result in
such person owning 15 percent or more of the common stock. Each one
one-thousandth of a share of the new preferred stock has terms designed to make
it substantially the economic equivalent of one share of common stock. Prior to
someone acquiring 15 percent, the rights can be redeemed for $0.001 each by
action of the board of directors. Under certain circumstances, if someone
acquires 15 percent or more of the common stock, the rights permit the
stockholders other than the acquirer to purchase the Company's common stock
having a market value of twice the exercise price of the rights, in lieu of the
preferred stock. Alternatively, when the rights become exercisable, the board of
directors may authorize the issuance of one share of common stock in exchange
for each right that is then exercisable. In addition, in the event of certain
business combinations, the rights permit the purchase of the common stock of an
acquirer at a 50 percent discount. Rights held by the acquirer will become null
and void in both cases. The rights expire on February 23, 2009.

6. STOCKHOLDERS' EQUITY:

   Preferred Stock

     With the closing of the Company's IPO in December 1997, all of the
outstanding convertible preferred stock automatically converted into common
stock. Upon conversion of the outstanding preferred stock to common stock, such
preferred stock was retired. The Company is authorized to issue 3,000,000 shares
of new $0.001 par value preferred stock, of which none was issued or outstanding
during each of the three years ended December 31, 2000.

                                       44


                           POWER INTEGRATIONS, INC.

            NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(Continued)

Common Stock

     As of December 31, 2000, the Company was authorized to issue 140,000,000
shares of $0.001 par value common stock. On October 25, 1999, the Company's
Board of Directors approved a two-for-one split of the Company's common stock,
in the form of a 100 percent stock dividend, which was applicable to
stockholders of record at the close of business on November 8, 1999, and
effective on November 22, 1999. All references to share and per-share data for
all periods presented have been adjusted to give effect to this two-for-one
stock split.

   1988 Stock Option Plan

     In June 1988, the board of directors approved the 1988 Stock Option Plan
(the "1988 Plan"), whereby the board of directors may grant options to key
employees, directors and consultants to purchase the Company's common stock at
exercise prices of not less than 85% of the fair value of the shares at the date
of grant. Options expire ten years after the date of grant (five years if the
option is granted to a ten percent owner optionee) and generally vest over 50
months. Options granted under the 1988 Plan will remain outstanding in
accordance with their terms, but effective July 1997, the board of directors had
determined that no further options would be granted under the 1988 Plan.

   1997 Stock Option Plan

     In June 1997, the board of directors approved the 1997 Stock Option Plan
(the "1997 Plan"), whereby the board of directors may grant options to key
employees, directors and consultants to purchase the Company's common stock at
exercise prices of not less than 85% of the fair value of the shares at the date
of grant. The 1997 Plan allows for annual increases on the first day of the
Company's fiscal year (beginning in 1999) by a number of shares equal to five
percent of the number of shares of common stock issued and outstanding on the
last day of the preceding fiscal year. As of December 31, 2000, the 1997 Plan's
maximum share reserve is 6,837,573 shares, which is comprised of the sum of (i)
3,894,609 shares (new shares allocated to the 1997 Plan) and (ii) 2,942,964
shares granted pursuant to the 1988 Plan (the "1988 Plan Options"). The number
of shares available for issuance under the 1997 Plan, at any time, is reduced by
the number of shares remaining subject to the 1988 Plan Options. Options expire
ten years after the date of grant (five years if the option is granted to a ten
percent owner optionee) and generally vest over 48 months.

   1997 Outside Directors Stock Option Plan

     In September 1997, the board of directors approved an Outside Director
Stock Option Plan (the "Directors Plan"). A total of 800,000 shares of common
stock have been reserved for issuance under the Directors Plan. The Directors
Plan provides for the grant of nonstatutory stock options to nonemployee
directors of the Company. The Directors Plan is designed to work automatically
without administration; however, to the extent administration is necessary, it
will be performed by the board of directors. The Directors Plan provides that
each current and future nonemployee director of the Company will be granted an
option to purchase 30,000 shares of common stock on the effective date or the
date on which the optionee first becomes a nonemployee director of the Company
after the effective date as the case may be (the "Initial Grant"). Thereafter,
each nonemployee director who has served on the board of directors continuously
for 6 months will be granted an additional option to purchase 10,000 shares of
common stock (an "Annual Grant"). Subject to an optionee's continuous service
with the Company, approximately 1/3rd of an Initial Grant will become
exercisable one year after the date of grant and 1/36th of the Initial Grant
will become exercisable monthly thereafter. Each Annual Grant will become
exercisable in twelve monthly installments beginning in the 25th month after the
date of grant, subject to the optionee's continuous service. The exercise price
per share of all options granted under the Directors Plan will equal the fair
market value of a share of common stock on the date of grant. Options granted
under the Directors Plan have a term of ten years and are non-transferable. In
the event of certain changes in control of the Company, options outstanding
under the Directors Plan will become immediately exercisable and vested in full.

                                       45


                           POWER INTEGRATIONS, INC.

            NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(Continued)


1998 Nonstatutory Stock Option Plan

     In July 1998, the board of directors approved the 1998 Nonstatutory Stock
Option Plan (the "1998 Plan"), whereby the board of directors may grant
nonstatutory options to employees and consultants to purchase the Company's
common stock at exercise prices of not less than 85% of the fair value of the
shares at the date of grant. As of December 31, 2000, the maximum share reserve
under this plan was 1,000,000 shares. Options expire ten years after the date of
grant (five years if the option is granted to a ten percent owner optionee) and
generally vest over 48 months.

     The following table summarizes option activity under the Company's option
plans:

      (prices are weighted average prices)



                                                            Year Ended December 31,
                                                            -----------------------
                                            2000                      1999                      1998
                                            ----                      ----                      ----

                                    Shares        Price       Shares        Price       Shares        Price
                                    ------        -----       ------        -----       ------        -----
                                                                                  
Options outstanding,
    Beginning of year............   3,329,075     $ 10.40     2,666,422    $   3.11     1,749,512    $   1.38
     Granted.....................   1,523,285     $ 18.97     1,704,875    $  18.06     1,317,300    $   5.08
     Exercised...................    (706,969)    $  4.22      (769,316)   $   2.15      (275,476)   $   0.89
     Cancelled...................    (334,072)    $ 14.78      (272,906)   $  11.23      (124,914)   $   3.28
                                    ---------                 ---------                 ----------
Options outstanding,
    end of year..................   3,811,319     $ 14.59     3,329,075    $  10.40     2,666,422    $   3.11
                                    =========                 =========                 =========

Exercisable, end of year.........   1,072,644     $  9.81       723,496    $   3.71       727,348    $   1.11
                                    =========                 =========                 =========


      Options issued under the 1988, 1997 and 1998 plans may be exercised at any
time prior to their expiration. Options issued under the Directors Plan are
exercisable upon vesting. In addition, the Company has the right, upon
termination of an optionholder's employment or service with the Company, at its
discretion, to repurchase any unvested shares issued under the 1988, 1997 and
1998 plans at the original purchase price. Under the terms of the option plans,
an option holder may not sell shares obtained upon the exercise of an option
until the option has vested as to those shares. As of December 31, 2000, an
aggregate of 91,051 shares of common stock issued under the 1988, 1997 and 1998
plans are subject to repurchase by the Company at $0.68 to $14.22 per share and
a weighted average repurchase price of $4.56 per share.

      The Company accounts for its Plans under APB Opinion No. 25, "Accounting
for Stock Issued to Employees." Had compensation expense for the Plans been
determined under a fair value method consistent with SFAS No. 123, "Accounting
for Stock Based Compensation," the Company's net income would have been
decreased to the following pro forma amounts (in thousands, except per share
information):




                                                                                     Year Ended December 31,
                                                                                     -----------------------
                                                                                     2000      1999      1998
                                                                                     ----      ----      ----
                                                                                              
Net income:
     As reported.................................................................    $19,765   $24,477   $12,678
     Pro forma...................................................................    $ 9,428   $18,891   $11,599
Basic earnings per share:
     As reported.................................................................    $  0.73   $  0.94   $  0.52
     Pro forma...................................................................    $  0.35   $  0.73   $  0.47
Diluted earnings per share:
     As reported.................................................................    $  0.69   $  0.87   $  0.48
     Pro forma...................................................................    $  0.33   $  0.67   $  0.44


                                       46


                           POWER INTEGRATIONS, INC.

            NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(Continued)

     The weighted-average grant date fair value of options granted during fiscal
years 2000, 1999 and 1998 was $15.72, $11.85 and $5.08, respectively. The fair
value of each option grant is estimated on the date of grant using the
Black-Scholes option pricing model with the following weighted average
assumptions used for grants in 2000, 1999 and 1998: risk-free interest rates of
5.77, 5.63 and 5.25 percent, respectively; expected dividend yields of zero
percent; expected lives of 4.2 years for 2000, and 1.5 years for 1999 and 1998;
expected volatility of 97%, 84% and 73% for 2000, 1999 and 1998, respectively.

     The following table summarizes the stock options outstanding at December
31, 2000:



                  Options Outstanding                                               Options Exercisable
- -----------------------------------------------------------------------    --------------------------------------
                                        Weighted         Weighted                                  Weighted
                                         Average         Average                                   Average
      Exercise            Number        Remaining        Exercise                Number            Exercise
        Price          Outstanding        Life            Price                Outstanding          Price
        -----          -----------        -----           -----                -----------          -----
                                                                                  
      $ 0.26--$ 0.85        211,791         5.51           $  0.63                 193,171           $  0.61
      $ 2.55--$ 4.38        678,908         7.41           $  4.25                 398,805           $  4.21
      $ 4.42--$12.28        385,829         7.99           $  9.67                 135,773           $  8.32
      $12.53--$14.22        751,138         8.47           $ 14.14                  52,133           $ 14.02
      $14.50--$15.06        938,538         9.21           $ 15.03                  98,164           $ 14.94
      $15.50--$23.25        275,449         9.20           $ 19.91                  54,048           $ 19.38
      $23.56--$51.50        569,666         8.83           $ 32,69                 140,550           $ 31.00
                          ---------         ----           -------               ---------           -------
      $ 0.26--$ 51.50     3,811,319         8.36           $ 14.59               1,072,644           $  9.81
                          =========         ====           =======               =========           =======


   1997 Employee Stock Purchase Plan

     Under the 1997 Employee Stock Purchase Plan (the "Purchase Plan"),
1,500,000 shares of common stock are reserved for issuance to eligible
employees. The Purchase Plan permits employees to purchase common stock through
payroll deductions, which may not exceed 15 percent of an employee's
compensation, at 85% of the lower of the fair market value of the Company's
common stock on the first or the last day of each offering period. As of
December 31, 2000, 792,825 shares had been purchased and 707,175 shares were
reserved for future issuance under the Purchase Plan.

   Stockholder Notes Receivable

     In July 1997, in connection with the purchase of common stock upon exercise
of stock options granted to certain officers and employees of the Company, the
Company loaned to these officers and employees an aggregate of $405,000, at an
interest rate of 6.65% pursuant to Promissory Note and Pledge Agreements. These
loans, which are secured by 238,231 shares of common stock, are full recourse
notes, and are due in full without regard to the value of the Company's common
stock in July 2002, or at the Company's option upon (i) termination of
employment with the Company, (ii) a default in the payment of any installment or
principal and/or interest when due, (iii) a sale of the pledged stock or (iv)
acceleration being reasonably necessary for the Company to comply with any
regulations promulgated by the Board of Governors of the Federal Reserve System
affecting the extension of credit in connection with the Company's securities.
As of December 31, 2000, the unpaid principal portion of these loans was
$76,000.

   Deferred Compensation

     In connection with the issuance of stock options to employees and
consultants prior to December 1997, the Company recorded deferred compensation
in the aggregate amount of approximately $566,000, representing the difference
between the fair market value of the Company's common stock and the exercise
price of the stock

                                       47


                            POWER INTEGRATIONS, INC.

             NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(Continued)


options at the date of grant. The Company is amortizing the deferred
compensation expense over the shorter of the period in which the employee,
director or consultant provides services or the applicable vesting period, which
is typically over 48 months. Amortization expense was $140,000 in each of the
years ended December 31, 2000, 1999 and 1998. Compensation expense is decreased
in the period of forfeiture for any accrued, but unvested compensation arising
from the early termination of an option holder's services. Since recording the
deferred compensation in 1997, there have been no forfeitures.

   Shares Reserved

     As of December 31, 2000, the Company had 5,511,169 shares of common stock
reserved for future issuance under Stock Option and Stock Purchase Plans.

7.   INCOME TAXES:

     The Company accounts for income taxes under SFAS No. 109 "Accounting for
Income Taxes." SFAS No. 109 provides for an asset and a liability approach to
accounting for income taxes under which deferred income taxes are provided based
upon enacted tax laws and rates applicable to the periods in which taxes become
payable.

     The components of the provision for income taxes are as follows (in
thousands):



                                                                               Year Ended December 31,
                                                                               -----------------------
                                                                              2000      1999       1998
                                                                              ----      ----       ----
                                                                                        
          Current provision:
               Federal.....................................................  $10,214    $7,621     $1,886
               State.......................................................      393       616        694
               Foreign.....................................................       --        15         20
                                                                             -------    ------     ------
                                                                              10,607     8,252      2,600
                                                                             -------    ------     ------
          Deferred provision (benefit):
               Federal.....................................................   (1,759)    1,125      4,136
               State.......................................................     (377)       99       (103)
                                                                             -------    ------     ------
                                                                              (2,136)    1,224      4,033
                                                                             -------    ------     ------

          Net decrease in valuation allowance..............................       --    (5,142)    (4,033)
                                                                             -------    ------     ------
                                                                              $8,471    $4,334     $2,600
                                                                             =======    ======     ======


     The provision for income taxes differs from the amount, which would result
by applying the applicable Federal income tax rate to income before provision
for income taxes as follows:



                                                                               Year Ended December 31,
                                                                               -----------------------
                                                                              2000      1999       1998
                                                                              ----      ----       ----
                                                                                        
          Provision computed at Federal statutory rate.....................    35.0%     35.0%      35.0%
          State tax provision, net of Federal benefit......................     3.1       3.1        3.1
          Foreign tax......................................................      --        --        0.1
          Change in valuation allowance....................................      --     (17.9)     (23.0)
          Research and development credits.................................    (2.9)     (3.4)      (3.0)
          Foreign sales corporation........................................    (4.9)     (2.5)        --
          Non deductible expenses and other................................    (0.3)      0.7        4.8
                                                                              -----     -----      -----
                                                                               30.0%     15.0%      17.0%
                                                                              =====     =====      =====


                                       48


                           POWER INTEGRATIONS, INC.

            NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(Continued)

     The components of the net deferred income tax asset were as follows (in
thousands):



                                                                                       December 31,
                                                                                       ------------
                                                                                      2000       1999
                                                                                      ----       ----
                                                                                         
          Tax credit carry-forwards..............................................    $ 1,155   $    494
          Inventory reserves.....................................................      2,218      1,896
          Accounts receivable allowances.........................................        542        377
          Accrued vacation.......................................................        294        121
          Other cumulative temporary differences.................................      1,845      1,030
                                                                                     -------   --------
                                                                                     $ 6,054   $  3,918
                                                                                     =======   ========



     Realization of the deferred tax asset is dependent on generating sufficient
future taxable income. Although realization is not assured, management believes
it is more likely than not that all of the deferred tax asset will be realized.

     As of December 31, 2000, the Company had research and development tax
credit carryforwards of approximately $1.2 million. These carry-forwards expire
on various dates through 2020. The United States Tax Reform Act of 1986 contains
provisions that limit research and development credits available to be used in
any given year upon the occurrence of certain events.

8.  LEGAL PROCEEDINGS:

     In August 1998, the Company filed a complaint in the U.S. District Court,
District of Delaware, alleging that Motorola had infringed two of the Company's
circuit patents. On October 15, 1999, the jury returned a unanimous verdict in
favor of the Company and determined that Motorola had willfully infringed one of
the Company's patents and awarded the Company $32.3 million in compensatory
damages. In March 2000, the Company and Motorola entered into a settlement
agreement, pursuant to which, the Court issued a permanent injunction
prohibiting Motorola from selling the ICs that were the subject of the lawsuit.
Additionally, the Company agreed not to collect the money judgment from Motorola
and will continue as a preferred supplier of high-voltage power conversion ICs
for cellular phone chargers that Motorola manufactures.

                                      49


                           POWER INTEGRATIONS, INC.

                SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS

                                (In thousands)




                                                                  Balance at   Charged to                  Balance at
                                                                 Beginning of   Costs and                    End of
                  Classification                                    Period      Expenses     Deductions      Period
- ----------------------------------------------------------      -------------  ----------    ----------    ----------
                                                                                               
Allowances for doubtful accounts and customer returns:
    Year ended December 31, 1998..........................         $ 1,269       $   838      $   (814)       $ 1,293
    Year ended December 31, 1999..........................         $ 1,293       $   129      $   (432)       $   990
    Year ended December 31, 2000..........................         $   990       $ 1,084      $ (1,006)       $ 1,068


                                      50


                                  SIGNATURES

     Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this Report to be signed on
its behalf by the undersigned, thereunto duly authorized.

                                             POWER INTEGRATIONS, INC.


Dated: March 20, 2001                        By:     /s/ ROBERT J. LELIEUR
                                                --------------------------------
                                                        Robert J. Lelieur
                                                 Acting Chief Financial Officer

                                      51


                               POWER OF ATTORNEY

     KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Howard F. Earhart and Robert J. Lelieur
his true and lawful attorney-in-fact and agent, with full power of substitution
and, for him and in his name, place and stead, in any and all capacities to sign
any and all amendments to this Report on Form 10-K, and to file the same, with
all exhibits thereto and other documents in connection therewith, with the
Securities and Exchange Commission, granting unto said attorney-in-fact and
agent full power and authority to do and perform each and every act and thing
requisite and necessary to be done in connection therewith, as fully to all
intents and purposes as he might or could do in person, hereby ratifying and
confirming all that said attorney-in-fact and agent, or his substitute or
substitutes, may lawfully do or cause to be done by virtue hereof.

PURSUANT TO THE REQUIREMENTS OF THE SECURITIES EXCHANGE ACT OF 1934, THIS REPORT
HAS BEEN SIGNED BY THE FOLLOWING PERSONS ON BEHALF OF THE REGISTRANT AND IN THE
CAPACITIES AND ON THE DATES INDICATED.

                                            /s/  HOWARD F. EARHART
Dated: March 20, 2001                  By:--------------------------------------
                                            Howard F. Earhart
                                            President, Chief Executive Officer
                                            and Chairman of the Board
                                            (Principal Executive Officer)

                                            /s/  ROBERT J. LELIEUR
Dated: March 20, 2001                  By:--------------------------------------
                                            Robert J. Lelieur
                                            Acting Chief Financial Officer
                                            (Principal Financial and Principal
                                            Accounting Officer)

                                            /s/  ALAN D. BICKELL
Dated: March 20, 2001                  By:--------------------------------------
                                            Alan D. Bickell
                                            Director

                                            /s/  NICHOLAS E. BRATHWAITE
Dated: March 20, 2001                  By:--------------------------------------
                                            Nicholas E. Brathwaite
                                            Director

                                            /s/  R. SCOTT BROWN
Dated: March 20, 2001                  By:--------------------------------------
                                            R. Scott Brown
                                            Director

                                            /s/  E. FLOYD KVAMME
Dated: March 20, 2001                  By:--------------------------------------
                                            E. Floyd Kvamme
                                            Director

                                            /s/  STEVEN J. SHARP
Dated: March 20, 2001                  By:--------------------------------------
                                            Steven J. Sharp
                                            Director

                                      52


                            POWER INTEGRATIONS, INC

                                   EXHIBITS
                                      TO
                            FORM 10-K ANNUAL REPORT

                              For the Year Ended
                               December 31, 2000

EXHIBIT NUMBER                              DESCRIPTION
- --------------                              -----------

  3.1***                 Restated Certificate of Incorporation (we also filed in
                         our Current Report on Form 8-K filed with the SEC on
                         March 12, 1999, a Certificate of Designation which
                         amends this Restated Certificate).

  3.2*++                 By-Laws, as amended February 24, 1999.

  4.1*                   Fifth Amended and Restated Rights Agreement dated April
                         27, 1995, as amended, by and among us and certain of
                         our investors.

  4.2*                   Investors' Rights Agreement dated as of May 22, 1996
                         between us and Hambrecht & Quist Transition Capital,
                         LLC.

  10.1*                  Form of Indemnification Agreement for directors and
                         officers.

  10.2*                  1988 Stock Option Plan and forms of agreements
                         thereunder.

  10.3*                  1997 Stock Option Plan and forms of agreements
                         thereunder.

  10.4*                  1997 Outside Directors Stock Option Plan and forms of
                         agreements thereunder.

  10.5*                  1997 Employee Stock Purchase Plan and forms of
                         agreements thereunder.

  10.6*                  Amended Technology License Agreement dated as of June
                         29, 1995, as amended on April 1, 1997 between us and
                         Matsushita.

  10.7*                  Amended Wafer Foundry Agreement dated as of June 29,
                         1997, between us and Matsushita.

  10.9*                  Master Equipment Lease Agreement dated as of February
                         11, 1997 among us and Finova Technology Finance, Inc.

  10.10*                 Master Lease Agreement dated as of September 3, 1996
                         between us and Leasing Technologies International, Inc.

  10.11*                 Master Equipment Lease Agreement dated as of November
                         17, 1995 between us and Lighthouse Capital Partners,
                         L.P.

  10.12*                 Master Equipment Lease Agreement dated as of December
                         29, 1993, as amended, between us and MMC/GATX
                         Partnership No. 1.

                                      53


  10.14*                 Founder Stock Purchase Agreement between us and Steven
                         J. Sharp dated as of April 13, 1988.

  10.15*                 Founder Stock Purchase Agreement between us and Klas H.
                         Eklund dated as of April 13, 1988.

  10.16*                 Founder Stock Purchase Agreement between us and Arthur
                         E. Fury dated as of April 13, 1988.

  10.18**                Industrial Building Lease between us and Mathilda
                         Development, a California limited partnership, dated as
                         of June 3, 1998.

  10.21+                 Wafer Supply Agreement between us and OKI, dated as of
                         October 1, 1998.

  10.22+                 Master Equipment Lease Agreement between us and Metlife
                         Capital Limited Partnership, dated as of July 31, 1998.

  10.23***               Loan Agreement between us and Union Bank of California,
                         N.A., dated as of October 16, 1998.

  10.24+++               Amendment Number One, dated as of February 26, 1999, to
                         the Wafer Supply Agreement between us and OKI, dated as
                         of October 1, 1998.

  10.25****              Sublease between us and Atweb, dated as of July 1,
                         1999.

  10.26++++              Lease agreement dated as of December 29, 1999 between
                         us and Lincoln - RECP Hellyer OPCO, LLC, a Delaware
                         limited liability company.

  10.27*****             Wafer Supply Agreement between us and Matsushita, dated
                         as of June 29, 2000.

  10.28*****             Technology License Agreement between us and Matsushita,
                         dated as of June 29, 2000.

  10.29*****             First Amendment to Loan Agreement dated October 16,
                         1998 between us and Union Bank of California, N.A.,
                         dated August 1, 2000.

  21.1*                  List of subsidiaries.

  23.1                   Consent of Independent Public Accountants.

  24.1                   Power of Attorney (See signature page).

_____________
*      As filed with the SEC in our Registration Statement on Form S-1 on
       September 11, 1997.

**     As filed with the SEC in our quarterly report on Form 10-Q on August
       12, 1998.

***    As filed with the SEC in our annual report on Form 10-K on March
       16, 1999.

****   As filed with the SEC in our quarterly report on Form 10-Q on
       November 9, 1999.

*****  As filed with the SEC in our quarterly report on Form 10-Q on
       November 10, 2000.

+      As filed with the SEC in our quarterly report on Form 10-Q on
       November 10, 1998.

                                      54


++     We filed an amendment to the Bylaws with the SEC in our Current Report on
       Form 8-K on March 12, 1999.

+++    As filed with the SEC in our quarterly report on Form 10-Q on May 10,
       1999.

++++   As filed with the SEC in our annual report on Form 10-K on March 29,
       2000.

                                      55