Exhibit 5.1


                                January 17, 2001


Microchip Technology Incorporated
2355 West Chandler Boulevard
Chandler, Arizona 85224


RE: Registration Statement on Form S-8


Ladies and Gentlemen:

     We have examined the Registration  Statement on Form S-8 to be filed by you
with the  Securities  and Exchange  Commission  on or about January 18, 2001, in
connection with the  registration  under the Securities Act of 1933, as amended,
of 1,905,180 shares of Common Stock of Microchip  Technology  Incorporated  (the
"Shares")  to be issued  under  TelCom  Semiconductor,  Inc.'s 1994 Stock Option
Plan,  1996 Director  Option Plan,  1996 Employee  Stock  Purchase Plan and 2000
Nonstatutory Stock Option Plan (each, a "Plan").

     As your legal  counsel,  we have  examined  the  proceedings  taken and are
familiar with the proceedings proposed to be taken by you in connection with the
sale and issuance of the Shares. It is our opinion that the Shares,  when issued
and sold in the manner referred to in each Plan, as applicable,  and pursuant to
the agreements  which  accompany  each Plan, as applicable,  will be legally and
validly issued, fully paid and nonassessable.

     We  consent to the use of this  opinion as an exhibit to said  Registration
Statement and further consent to the use of our name wherever  appearing in said
Registration Statement and any amendments thereto.


                                   Sincerely yours,


                                   /s/ WILSON SONSINI GOODRICH & ROSATI
                                   Professional Corporation