The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 13, 1998
Filed:
Jul. 31, 1996
Lawrence Tze-Leung Tse, Fremont, CA (US);
King Cheung Yen, San Jose, CA (US);
Chrontel, Inc., San Mateo, CA (US);
Abstract
A color space converter is implemented using current mode analog circuitry to efficiently transform video data from a YC.sub.b C.sub.r format to an RGB format in order to allow the display of video signals on a color monitor. The analog current-mode circuitry is implemented in an integrated circuit that will operate at high clock rates and can be integrated in a small die area so as to reduce its cost. The color space converter includes Y, C.sub.b and C.sub.r current-mode conversion circuits to compute Y, C.sub.b and C.sub.r contributions to the G, R and B signals, and current-mode adders that add those contributions to the G, R and B signals to generate the G, R and B signals. Each conversion circuit includes (A) a respective folded cascode structure having an input coupled to a respective analog Y, C.sub.b or C.sub.r signal, each conversion circuit generating a respective Y, C.sub.b or C.sub.r current output; (B) at least one respective current mirror that generates from the Y, C.sub.b or C.sub.r current output an unadjusted Y, C.sub.b or C.sub.r contribution to at least one of the G, R and B signals, and (C) at least one current adder for subtracting respective offset currents from the unadjusted Y, C.sub.b or C.sub.r contribution to at least one of the G, R and B signals to provide the Y, C.sub.b or C.sub.r contribution to at least one of the G, R and B signals.