Exhibit 10.28

          FEBRUARY 3, 2003 AMENDMENT TO THE ADOPTION AGREEMENT TO THE
         MICROCHIP TECHNOLOGY INCORPORATED SUPPLEMENTAL RETIREMENT PLAN

1.03 COVERAGE

     (a)  ONLY THOSE EMPLOYEES LISTED IN ATTACHMENT A WILL BE ELIGIBLE TO
          PARTICPATE IN THE PLAN.

     (b)  THE ENTRY DATE(S) SHALL BE (CHECK ONE):

          (1)  [ ] the first day of each Plan Year.

          (2)  [ ] the first day of each Plan Year and the date six months
                   later.

          (3)  [ ] the first day of each Plan Year and the first day of the
                   fourth, seventh, and tenth months.

          (4)  [X] the first day of each month.

1.04 COMPENSATION

     FOR PURPOSES OF DETERMINING CONTRIBUTIONS UNDER THE PLAN, COMPENSATION
     SHALL BE AS DEFINED IN SECTION 2.01(a)(6), BUT EXCLUDING (CHECK THE
     APPROPRIATE BOX(ES)):

     (a)  [X] Overtime Pay.

     (b)  [ ] Bonuses.

     (c)  [X] Commissions.

     (d)  [X] The value of a qualified or a non-qualified stock option granted
              to an Employee by the Employer to the extent such value is
              includable in the Employee's taxable income.

     (e)  [ ] No exclusions.

1.05 CONTRIBUTIONS

     (a)  DEFERRAL CONTRIBUTIONS. THE EMPLOYER SHALL MAKE A DEFERRAL
          CONTRIBUTION IN ACCORDANCE WITH SECTION 4.01 ON BEHALF OF EACH
          PARTICIPANT WHO HAS AN EXECUTED SALARY REDUCTION AGREEMENT IN EFFECT
          WITH THE EMPLOYER FOR THE PLAN YEAR (OR PORTION OF THE PLAN YEAR) IN
          QUESTION, NOT TO EXCEED 50% COMPENSATION FOR THAT PLAN YEAR.

Effective: January 1, 2000
Authorized Signer: Sue Flores
Date: 12/9/99

                                                  Effective date: 3/31/03
                                                  Authorized signer: Linda Croft
                                                  Date: 1/30/03

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