LIMITED POWER OF ATTORNEY
FOR MONOLITHIC POWER SYSTEMS
SECTION 16(a) FILINGS
Know all by these presents, that the undersigned, Saria Tseng,
hereby constitutes and appoints each of Michael Hsing and
Meera Rao, signing singly, the undersigned's true and lawful
attorney-in-fact to:
(1) Complete and execute for and on behalf of the undersigned, in the
undersigned's capacity as an officer, director and/or stockholder of
Monolithic Power Systems, Inc. (the "Company"), Forms ID, 3, 4, and 5
and other forms and all amendments thereto as such attorney-in-fact
shall in his or her discretion determine to be required or advisable
in accordance with Section 16(a) of the Securities Exchange Act of
1934 and the rules and regulations promulgated thereunder, or any
successor laws and regulations, as consequence of the undersigned's
ownership, acquisition or disposition of securities of the Company;
(2) Do and perform any and all acts for and on behalf of the
undersigned which may be necessary or desirable to complete and execute
any such forms or amendment thereto and timely file such forms with the
United States Securities and Exchange Commission (the "SEC") and any
stock exchange or similar authority; and
(3) Take any other action of any type whatsoever which, in the opinion
of such attorney-in-fact, may be necessary or desirable in connection
with the foregoing authority, it being understood that the documents
executed by such attorney-in-fact on behalf of the undersigned pursuant
to this Power of Attorney shall be in such form and shall contain such
terms and conditions as such attorney-in-fact may approve.
The undersigned hereby grants to each such attorney-in-fact full power
and authority to do and perform any and every act and thing whatsoever
requisite, necessary, or proper to be done in the exercise of any of
the rights and powers herein granted, as fully to all intents and purposes
as the undersigned might or could do if personally present, with full
power of substitution or revocation, hereby ratifying and confirming all
that such attorney-in-fact, or such attorney-in-fact's substitute or
substitutes, shall lawfully do or cause to be done by virtue of this
Power of Attorney and the rights and powers herein granted. The
undersigned acknowledges that the foregoing attorneys-in-fact, in serving
in such capacity at the request of the undersigned, are not assuming,
nor is the Company assuming, any of the undersigned's responsibilities
to comply with Section 16 of the Securities Exchange Act of 1934.
This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms ID, 3, 4, and 5 with
respect to the undersigneds holdings of and transaction in securities
of the Company, unless earlier revoked by the undersigned in a signed
writing delivered to the Company and the foregoing attorneys-in-fact.
This Power of Attorney may be filed with the SEC as a confirming statement
of the authority granted herein.
IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney
to be executed as of this day of July 25, 2011.
__Saria Tseng       ________
Print Name of Reporting Person


__ /s/Saria Tseng________
Signature