POWER OF ATTORNEY
KNOW ALL BY THESE PRESENTS, that the undersigned
hereby constitutes and appoints each of CLAUDIA BARANOWSKI,
SCOTT DAWSON and CYNTHIA MORELAND, signing individually,
as the undersigned's true and lawful attorney-in fact and agent to:
(1)	execute for and on behalf of the undersigned, an
officer or director of Applied Micro Circuits Corporation
(the "Company"), Forms 3, 4 and 5 in accordance with
Section 16(a) of the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), and the rules thereunder;
(2)	do and perform any and all acts for and on behalf
of the undersigned that may be necessary or desirable to
complete and execute such Form 3, 4 or 5, complete and
execute any amendment or amendments thereto, and timely
file such forms or amendments with the U.S. Securities and
Exchange Commission and any stock exchange or similar
authority; and
(3)	take any other action of any nature whatsoever in
connection with the foregoing, which in the opinion of such
attorney-in-fact may be of benefit, in the best interest of, or
legally required by, the undersigned, 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 in
such attorney-in-fact's discretion.
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 Exchange Act, and the undersigned hereby
agrees to indemnify and hold harmless each of the attorneys-in-fact
and the Company from any liabilities or damages that arise out of
the performance or failure to perform any of the actions described
herein.
This Power of Attorney shall remain in full force and effect
until the earliest to occur of (a) the undersigned is no longer
required to file Forms 3, 4 and 5 with respect to the undersigned's
holdings of and transactions in securities issued by the Company,
(b) revocation by the undersigned in a signed writing delivered to
the foregoing attorneys-in-fact or (c) as to any attorney-in-fact
individually, until such attorney-in-fact shall no longer be
employed by the Company.
IN WITNESS WHEREOF, the undersigned has cause this
Power of Attorney to be executed as of this 23rd day of August,
2005.

/s/ Julie H. Sullivan
[Signature]
Julie H. Sullivan
[Name]