Patent ID: 6731344
Filing Date: 2004-05-04
Classification: H04N

Abstract:
A horizontal automatic frequency control (AFC) circuit used in a display having a cathode ray tube (CRT) and a horizontal deflection yoke for performing horizontal deflection of the CRT, the display receiving a video signal and displaying the video signal on the CRT, said horizontal AFC circuit comprising:a synchronous separator for generating a horizontal (H) reference pulse from the video signal; an Hout circuit for generating, from an output of said synchronous separator, a horizontal driving pulse which drives the horizontal deflection yoke; a horizontal deflection driver for driving, in responsive to the horizontal driving pulse, the horizontal deflection yoke to control the horizontal deflection of the CRT and for generating a flyback pulse; a line memory into which each line of the video signal is written with a write clock (WCK) from the H reference pulse, and from which the written video signal with a read clock (RCK) synchronized with the flyback pulse from the flyback pulse; and a read clock generator for generating the RCK from the flyback pulse and the WCK.