Exhibit 10.84

                             MICROSEMI CORPORATION
                    SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

  Effective September 15, 1986 (the "Effective Date"), Microsemi Corporation
(the "Company") hereby establishes the Microsemi Corporation Supplemental
Executive Retirement Plan (the "Plan") for the benefit of those Participants and
their Beneficiaries set forth on Exhibit "A" attached to the Plan, and
incorporated herein by this reference.


                                   ARTICLE I
                              PURPOSE OF THE PLAN

  1.1  Plan Purpose.  The Plan is established for the purpose of providing
       ------------                                                       
retirement benefits for a select group of management or highly compensated
employees of the Company and is intended to be an unfunded plan within the
meaning of the Employee Retirement Income Security Act of 1974 ("ERISA").  All
benefits under the Plan will be provided solely from the general assets of the
Company.  It is intended that the Plan be exempt from Parts II, III and IV of
Title I of ERISA pursuant to ERISA Sections 201(2), 301(a)(3) and 401(a)(1).


                                  ARTICLE II
                                 PARTICIPATION

  2.1  Eligibility.  The Board of Directors of the Company (the "Board"), in its
       -----------                                                              
sole discretion, has designated those individuals eligible to participate in the
Plan.  Each individual so designated shall automatically become a participant
("Participant") as of the date determined by the Board.  Each Participant who
has commenced participation in the Plan shall continue to be a Participant until
he or she terminates his or her employment with the Company by reason of his or
her retirement, death, disability, resignation, dismissal or otherwise.
Notwithstanding the foregoing, the Board expressly reserves the right to remove
any Participant under the Plan from participation in the Plan at any time for
cause prior to the Participant's Retirement Date.  The persons designated as
Participants as of the Effective Date are those individuals set forth on Exhibit
"A" attached hereto and incorporated herein by this reference.


                                  ARTICLE III
                               AMOUNT OF BENEFIT

  3.1  Retirement Benefit.  Commencing with the Commencement Date and
       ------------------                                            
terminating on the first day of the 119th calendar month following the
Commencement Date (the "Pension Period"), the Company shall pay each Retiree an
amount equal to his Monthly Benefit.  In the event that the Retiree dies after
the Commencement Date, the Monthly Benefit shall be paid to the Beneficiary for
the remainder of the Pension Period.

  3.2  Death Benefit.  In the event that a Participant dies while he or she is
       -------------                                                          
an employee of the Company, commencing with the Beneficiary Commencement Date
and terminating on the first day of the 119th calendar month following the
Beneficiary Commencement Date (the "Death Benefit Period"), the Company shall
pay the Beneficiary an amount equal to the Monthly Death Benefit.  In the event
that the Beneficiary dies after the Beneficiary Commencement Date, the Monthly
Death 

 
Benefit shall be paid to the Beneficiary's estate during the Death Benefit
Period.

  3.3  Definitions.  As used in this Agreement, the following defined terms
       -----------                                                         
shall mean:

  (a) Beneficiary.  "Beneficiary" means:
      -----------                       

     (i)   the Participant's surviving spouse;

     (ii)  If his or her surviving spouse is still alive, the Participant may
           designate another person to be the Beneficiary only if his or her
           spouse consents in writing to the designation of such person as the
           Beneficiary and the consent acknowledges the effect of the
           designation and is witnessed by an officer of the Company or a notary
           public, or it is established to the satisfaction of an officer of the
           Company that the consent required under this paragraph may not be
           obtained because there is no spouse, the spouse cannot be located, or
           such other circumstances as may be authorized by the Board.

     (iii) In the case where a deceased Participant failed to designate a
           Beneficiary, the Board is unable to locate a designated Beneficiary,
           the Beneficiary predeceased the Participant, or the designation of
           the Beneficiary by the Participant is legally ineffective, any
           distribution on behalf of a Participant shall be paid to the person
           or persons included in the highest priority category among the
           following:

                (A)  The Participant's surviving Spouse;

                (B)  The Participant's surviving children, including adopted
                children;

                (C)  The Participant's surviving parents;

                (D)  The Participant's surviving brothers and sisters (whether
                whole or half-blood); or

                (E)  The Participant's estate.  In the event the Participant has
                neither a surviving spouse nor a properly designated
                Beneficiary, the remaining portion of his benefit shall be made
                to his estate.

 (b)  Beneficiary Commencement Date.  "Beneficiary Commencement Date" means the
      -----------------------------                                            
first day of the calendar month following the calendar month in which a
Participant dies.

 (c)  Commencement Date. "Commencement Date" means the first day of the calendar
      -----------------
month following the calendar month in which a Participant attains his Retirement
Date.

 (d)  Monthly Benefit.  "Monthly Benefit" means one-twelfth of a Participant's
      ---------------                                                         
Plan Benefit for the Plan Year in which the Participant commences retirement.

 (e)  Monthly Death Benefit.  "Monthly Death Benefit" means one-twelfth of a
      ---------------------                                                 
Participant's Plan Benefit for the Plan Year in which the Participant dies.

 (f)  Plan Year.  "Plan Year" means the calendar year, January 1 through
      ---------                                                         
December 31.

                                       2

 
 (g) Retiree.  "Retiree" means a Participant who has attained his Retirement    
     -------                                                                
Date.

 (h)  Retirement Date.  "Retirement Date" means the date on which a Participant
      ---------------                                                          
terminates his employment with the Company after he or she has retired from
employment with the Company and has been designated as a Retiree by the Board of
Directors, in its sole and absolute discretion.

 (i)  Years of Service.  "Years of Service" means a Plan Year in which the
      ----------------                                                    
Participant was employed on a full time basis by the Company on each business
day during the Plan Year.

  3.4  Payees under Legal Disability.  If the Board reasonably believes that any
       -----------------------------                                            
payee is legally incapable of giving a valid receipt and discharge for any
payment due him, the Board may have the payment, or any part of it, made to the
person (or persons or institution) whom it reasonably believes is caring for or
supporting such payee.  Any such payment shall be a payment for the benefit of
the payee and shall, to the extent thereof, be a complete discharge of any
liability under the Plan to the payee.

  3.5  Payment of Benefits.  All payments under the Plan shall be delivered in
       -------------------                                                    
person or mailed to the last address of the Participant (or, in the case of the
death of the Participant, to that of the Beneficiary determined under the rules
of Section 3.3).  Each Participant shall be responsible for furnishing the
Committee with the Participant's correct current address and the correct current
name and address of the Beneficiary.

  3.6  Claims Procedure.  In the event a claim for benefit by either a
       ----------------                                               
Participant, Retiree or Beneficiary is denied (in whole or in part), the denial
and the appeal of the decision shall be handled in accordance with the
provisions of Department of Labor Regulation 2560.503-1.


                                  ARTICLE IV
                               BENEFITS UNFUNDED

  4.1  Benefits Unfunded.  The benefits under this Plan shall not be funded, but
       -----------------                                                        
shall constitute an unsecured liability payable, when due, by the Company out of
its general assets.

  4.2  Program to Satisfy Plan Obligations.  Notwithstanding Section 4.1 above,
       -----------------------------------                                     
the Board may, in its sole discretion, elect to set aside amounts ("Reserves")
for the purpose of paying benefits under the Plan.  Reserves, if any, may be in
an amount determined by the Board in its sole discretion.  Reserves may be
invested or not invested in the manner determined by the Board in its sole
discretion.  Should the Board decide to establish Reserves, the Reserves shall
remain assets of the Company.  In no event shall any Participant, Retiree or
Beneficiary have any right to any specific asset designated to be Reserves under
this Section.

                                       3

 
                                   ARTICLE V
                              VESTING OF BENEFITS

  5.1  Vesting.  Except as provided in this Article, all Participants are fully
       -------                                                                 
vested in their Accounts in the Plan.

  5.2  Termination for Cause.  In the event that a Participant's employment with
       ---------------------                                                    
the Company is terminated for cause by the Board, the Board, in its sole and
absolute discretion, may declare the benefits payable under Section 3.1 or 3.2
forfeited and may terminate the Company's obligation to pay future benefits to
that Participant, Retiree or Beneficiary under the Plan.

  5.3  Unfair Trade Practices.  Notwithstanding the provisions of Section 5.1,
       ----------------------                                                 
if a Participant, Retiree or Beneficiary either uses, divulges, furnishes or
makes accessible to anyone any knowledge or information with respect to any
confidential, proprietary or secret aspect of the business or any program of the
Company or engages in any act of unfair competition with the Company or accepts
employment or consults for a competitor of the Company, the Board, in its sole
and absolute discretion, may declare the benefits payable under Section 3.1 or
3.2 forfeited and may terminate the Company's obligation to pay future benefits
to that Participant, Retiree or Beneficiary under the Plan.

  5.4  Limitation on Vesting.  Notwithstanding the vesting of a Participant's
       ---------------------                                                 
benefits under this Article, a Participant's benefits under this Plan shall
remain an unsecured, unfunded promise to pay benefits by the Company.  All
benefits under the Plan, whether fully vested, partially vested or unvested, are
payable only in accordance with Article VI.


                                  ARTICLE VI
                              PLAN ADMINISTRATION

  6.1  Plan Administration.
       ------------------- 

  (a) Authority to control and manage the operation and administration of the
Plan shall be vested in the Board. The Board shall have all powers necessary to
supervise the administration of the Plan and control its operations.

  (b) In addition to any powers and authority conferred on the Committee
elsewhere in the Plan or by law, the Board shall have the following powers and
authority:

     (i)   To designate agents to carry out responsibilities relating to the
           Plan;

     (ii)  To administer, interpret, construe and apply this Plan and to answer
           all questions which may arise or which may be raised under this Plan
           by the Participant, Retiree, Beneficiary or other person whatsoever;

     (iii) To establish rules and procedures from time to time for the conduct
           of its business and for the administration and effectuation of its
           responsibilities under the Plan; and

     (iv)  To perform or cause to be performed such further acts as it may deem
           to be 

                                       4

 
           necessary, appropriate, or convenient for the operation of the Plan.

   (c) Any action taken in good faith by the Board in the exercise of authority
conferred upon it by this Plan shall be conclusive and binding upon the
Participant, Retiree and Beneficiaries. All discretionary powers conferred upon
the Board shall be absolute.

  6.2  Limitation on Liability.  No employee or member of the Board shall be
       -----------------------                                              
subject to any liability with respect to his duties under the Plan unless the
person acts fraudulently or in bad faith.  To the extent permitted by law, the
Company shall indemnify each member of the Board, and any other employee of the
Company with duties under the Plan who was or is a party, or is threatened to be
made a party, to any threatened, pending or completed proceeding, whether civil,
criminal, administrative, or investigative, by reason of the person's conduct in
the performance of his duties under the Plan.


                                  ARTICLE VII
                             MISCELLANEOUS MATTERS

  7.1  Amendment and Termination.  The Company expects the Plan to be permanent,
       -------------------------                                                
but since future conditions affecting the Company cannot be anticipated or
foreseen, the Company reserves the right to amend, modify, or terminate the Plan
at any time by action of the Board.  Upon termination of the Plan, all benefits
shall become payable to the Participants and Beneficiaries and shall be subject
to the provisions of Section 4.1.

  7.2  Benefits Not Alienable.  Benefits under the Plan may not be assigned or
       ----------------------                                                 
alienated, whether voluntarily or involuntarily.

  7.3  No Enlargement of Employee Rights.  This Plan is strictly a voluntary
       ---------------------------------                                    
undertaking on the part of the Company and shall not be deemed to constitute a
contract between the Company and the Participant or to be consideration for, or
an inducement to, or a condition of, the employment of the Participant.  Nothing
contained in the Plan shall be deemed to give the right to the Participant to be
retained in the employ of the Company or to interfere with the right of the
Company to discharge the Participant at any time.

     No person shall have any right to any benefits under this Plan, except to
the extent expressly provided herein.

  7.4  Governing Law.  To the extent not preempted by federal law, all legal
       -------------                                                        
questions pertaining to the Plan shall be determined in accordance with the laws
of the State of California.


  IN WITNESS WHEREOF, in order to record the adoption of the Plan, Microsemi
Corporation has caused this instrument to be executed by its duly authorized
officer to be effective January 1, 1994.

                                       MICROSEMI CORPORATION


                                       By:  /s/ Philip Frey, Jr.
                                            --------------------

                                            Its:  President, CEO
                                                  -----------------------------

                                       5

 
                                  EXHIBIT "A"

                 SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN (SERP)
                 ---------------------------------------------



                                 BENEFIT            SERVICE    
    NAME                        *CATEGORY             DATE     
    ----                        ---------           --------   
                                                      
    P. Frey                          1               7/5/71    
    J. Sandera                       1              11/15/71   
                                                               
    J. McKnight                      2               3/12/73   
    B. Brandt                        2               2/12/73   
    R. Robinson                      2                1/5/70   
    P. Kellogg                       2              10/12/64   
    J. Lim                           2               1/11/65   
    C. Schumacher                    2               7/12/76    


* Benefit Category:


1 - 30% of annual salary, defined as the cumulative total salary paid during the
    12 months prior to retirement (excluding all bonus, special allowances,
    401(k) payments, and any other special non-salary payments), shall be paid
    to the participant each year as an annual ONE LUMP SUM PAYMENT WHICH IS TO
    BE PAID ON THE FIRST DAY OF THE SECOND MONTH AFTER RETIREMENT, and on each
    anniversary thereafter for 10 payment years certain.

    Should the participant die prior to the final payment of the 10 payments,
    payments, up to the total of 10 such payments, are to be made to the estate
    of the employee on each scheduled payment date.

    Participants are fully vested and qualified for the benefits of the plan and
    may take full advantage of the SERP immediately or at any future date
    decided either by the Board of Directors or lacking such direction by the
    Board, according to participant choice.

2 - 20% of 1994 salary (excluding all 401(k), bonus or other special non-salary
    payments), shall be paid annually for 10 years certain, to the named
    participants upon their retirement by either their choice or the choice of
    the Company.

    30% of the 1994 salary (excluding all 401(k) or other special non-salary
    payments), shall be paid annually for 10 years certain to the named
    participants upon their retirement by either their choice or the choice of
    the Company, if they will have completed at least 30 years of credited
    employment with the Company.

 
     For all employment years between 20 and 30, the percentage of 1994 salary
     shall be a straight line interpolation, and for each month of employment
     beyond 20, and additional .00833 fraction of their 1994 salary shall be
     added to the 20% base of 20 years, up to a maximum of 30% after 30 years
     (i.e., +1% per year up to 30 years).

     The payments shall be made each month, starting upon the 1st day of the
     second month after retirement, and continue for 120 months.

     Should the participant die before payments have been completed, the
     remainder of the payments will be made to the estate of the participant.