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PROSPECTUS SUPPLEMENT
(To Prospectus dated October 19, 1999,
as supplemented on November 12, 1999)
OFFER TO EXCHANGE
11 1/2% SENIOR SUBORDINATED NOTES DUE 2009
FOR ANY AND ALL OUTSTANDING
11 1/2% SENIOR SUBORDINATED NOTES DUE 2009 OF
INTEGRATED CIRCUIT SYSTEMS, INC.
GUARANTEED BY ICS TECHNOLOGIES, INC., MICROCLOCK, INC. AND ICST, INC.
THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON
NOVEMBER 30, 1999 (AS SUCH DATE MAY BE EXTENDED, THE "EXPIRATION DATE").
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The exchange offer was originally scheduled to expire at 5:00 p.m.,
New York City time, on November 18, 1999. In order to allow note holders
additional time to consider the offer, we are extending the expiration date to
5:00 p.m., New York City time, on November 30, 1999.
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THE DATE OF THIS SUPPLEMENT IS NOVEMBER 19, 1999
