Exhibit 5.1


                                November 25, 2002

Microchip Technology Incorporated
2355 W. Chandler Boulevard
Chandler, Arizona  85244

     RE: REGISTRATION STATEMENT ON FORM S-8

Ladies and Gentlemen:

     In connection with the registration under the Securities Act of 1933, as
amended (the "Act"), of $5,000,000.00 in deferred compensation obligations (the
"Obligations") of Microchip Technology Incorporated (the "Company") issuable
under the Microchip Technology Incorporated Supplemental Retirement Plan (the
"Plan") on a Registration Statement on Form S-8 filed with the Securities and
Exchange Commission (the "Commission") on December 6, 2002 (the "Registration
Statement"), you have requested our opinion with respect to the matters set
forth below.

     In our capacity as your counsel in connection with such registration, we
are familiar with the proceedings taken and proposed to be taken by the Company
in connection with the issuance of the Obligations. In addition, we have made
such legal and factual examinations and inquiries, including an examination of
originals or copies certified or otherwise identified to our satisfaction of
such documents, corporate records and instruments, as we have deemed necessary
or appropriate for purposes of this opinion.

     In our examination, we have assumed the genuineness of all signatures, the
authenticity of all documents submitted to us as originals, and the conformity
to authentic original documents of all documents submitted to us as copies.

     We are opining herein as to the effect on the subject transaction only of
the federal securities laws of the United States, federal laws and regulations
under the Employee Retirement Income Security Act of 1974, as amended ("ERISA"),
and the General Corporation Law of the State of Delaware, and we express no
opinion with respect to the applicability thereto, or the effect thereon, of the
laws of any other jurisdiction, or in the case of Delaware, any other laws, or
as to any matters of municipal law or the laws of any local agencies within any
state.

     Subject to the foregoing, it is our opinion that (i) upon the issuance of
the Obligations in the manner contemplated by the Registration Statement and in
accordance with the terms of the Plan, such Obligations will be legally valid
and binding obligations of the Company, and (ii) the written provisions of the
Plan comply with the applicable requirements under ERISA.

Microchip Technology Incorporated
November 25, 2002
Page 2 of 2


     Our opinion is subject to: (i) the effect of bankruptcy, insolvency,
reorganization, moratorium or other similar laws now or hereafter in effect
relating to or affecting the rights or remedies of creditors; (ii) the effect of
general principles of equity, including without limitation concepts of
materiality, reasonableness, good faith and fair dealing and the possible
unavailability of specific performance or injunctive relief, regardless of
whether enforcement is considered in a proceeding in equity or at law; and (iii)
the effect of the laws of usury or other laws or equitable principles relating
to or limiting the interest rate payable on indebtedness.

     This opinion is rendered only to you and is solely for your benefit in
connection with the transactions covered hereby. This opinion may not be relied
upon by you for any other purpose, or furnished to, quoted to, or relied upon by
any other person, firm or corporation for any purpose, without our prior written
consent. We consent to your filing this opinion as an exhibit to the
Registration Statement.

                                        Sincerely,

                                        WILSON SONSINI GOODRICH & ROSATI
                                        Professional Corporation

                                        /s/ Wilson Sonsini Goodrich & Rosati

Palo Alto, California
November 25, 2002