HORIZONTAL AUTOMATIC FREQUENCY CONTROL (AFC) CIRCUIT

A horizontal automatic frequency control (AFC) used in a display having a display device such as a cathode ray tube (CRT) is provided. The AFC circuit reduces a horizontal distortion and horizontal jitter on the CRT. The AFC circuit includes a video signal processor for demodulating and converting an input video signal into a desired signal such as a YUV signal or an RGB signal, a synchronous separator for separating a synchronizing signal from the video signal, a dual-port line memory, an Hout generator for generating a horizontal driving pulse which drives a horizontal deflection yoke, a read clock generator for generating a read clock (RCK) signal which is synchronized in phase with a flyback pulse, and a horizontal deflection driver for controlling horizontal deflection of the CRT and generating the flyback pulse. The line memory absorbs a horizontal position change of a displayed image caused by a temperature change or a load change in the horizontal deflection driver.