EXHIBIT 99.1

 PMC-Sierra Calls Convertible Subordinated Notes Due August 15, 2006

    SANTA CLARA, Calif.--(BUSINESS WIRE)--Dec. 17, 2004--PMC-Sierra,
Inc. (Nasdaq:PMCS) today announced that it has called the remaining
balance of its outstanding 3.75% Convertible Subordinated Notes due
August 15, 2006 (the "Notes") for redemption on January 18, 2005. The
Notes bear CUSIP Nos. 69344F-AA-4 and 69344F-AB-2. There is
approximately $68.1 million aggregate principal amount of the Notes
outstanding.
    On or prior to the close of business on January 14, 2005, holders
of the Notes may elect to convert their Notes into common stock of
PMC-Sierra, Inc. at a conversion price of $42.43, or approximately
23.57 shares of common stock per $1,000 principal amount of Notes. The
Company will pay cash in lieu of fractional shares. On December 16,
2004 the last reported sale price of PMC-Sierra's common stock on the
NASDAQ National Market was $10.97 per share. To the extent that Note
holders do not convert their Notes into common stock of PMC-Sierra,
such Notes will be automatically redeemed on January 18, 2005, at a
total redemption price of approximately $1,030.94 per $1,000 amount of
Notes, consisting of $1,015 principal amount plus accrued interest of
approximately $15.94. The Company expects to pay cash redemptions from
its available cash and cash equivalent balances, and believes that
remaining sources of liquidity will satisfy its requirements through
the end of 2005.
    The Company is mailing a Notice of Redemption and a Letter of
Transmittal, which may be used to surrender notes for conversion or
redemption, to all holders of the Notes. Holders of Notes held in
book-entry form through the Depository Trust Company (DTC) must follow
the DTC's customary practices for surrendering the Notes. Holders who
hold their Notes in certificate form may convert their Notes or
receive the redemption price by surrendering their Notes to U.S. Bank
National Association, the conversion and redemption agent, as
stipulated in the Notice of Redemption. Copies of the Notice of
Redemption and Letter of Transmittal may be obtained from U.S. Bank by
calling Paula Oswald at 212-615-6043.
    From and after January 18, 2005, the Notes will cease to accrue
interest, and holders of the Notes will only have the right to receive
the redemption price plus accrued and unpaid interest.
    The above-referenced CUSIP numbers are included solely for the
convenience of the holders of the Notes. No representation is made as
to the correctness of such numbers.

    Safe Harbor Statement

    PMC-Sierra's forward-looking statement regarding the adequacy of
its cash requirements are subject to risks and uncertainties. Changes
in the Company's operating cash flow, foreign exchange, working
capital, venture investing, capital expenditures, wafer deposits and
remaining restructuring requirements may cause its actual requirements
to differ from these projections. In addition, the Company
contemplates mergers and acquisitions of other companies or assets as
part of its business strategy. Consequently, the Company may determine
in the future that its sources of liquidity are insufficient and it
may proceed with financing or other activities, which could dilute
stockholder ownership. The Company's SEC filings describe more fully
the risks associated with our liquidity and capital resources. The
Company does not undertake any obligation to update the
forward-looking statements.

    About PMC-Sierra

    PMC-Sierra(TM) is a leading provider of high speed broadband
communications and storage semiconductors and MIPS-Powered(TM)
processors for Enterprise, Access, Metro Optical Transport, Storage
Area Networking and Wireless network equipment. The company offers
worldwide technical and sales support, including a network of offices
throughout North America, Europe and Asia. The company is publicly
traded on the NASDAQ Stock Market under the PMCS symbol and is
included in the S&P 500 Index. For more information, visit
www.pmc-sierra.com.

    (C) Copyright PMC-Sierra, Inc. 2004. All rights reserved. PMC,
PMCS, PMC-Sierra, and "Thinking you can build on" are trademarks of
PMC-Sierra, Inc. All other trademarks are the property of the
respective owners.

    CONTACT: PMC-Sierra, Inc.
             Alan Krock, 408-988-1204
             Glen Kayll, 408-988-7717