Patent ID: 6147464
Filing Date: 2000-11-14
Classification: G09G,H04N

Abstract:
A compensation control circuit for compensating the variation of a horizontal scanning size due to an anode load current, the anode load current being generated by a secondary winding of a fly-back transformer in a monitor and outputted from a first terminal of the secondary winding, the horizontal scanning size being controlled by a horizontal deflection yoke with a first end connected to a horizontal scanning control signal, comprising:a horizontal scanning size compensation circuit, coupled to a second terminal of the secondary winding, for generating a compensation signal in response to the variation of the anode load current, the voltage of the compensation signal being lower than the voltage level at the first terminal of the secondary winding;a horizontal scanning size control circuit, coupled to the horizontal scanning size compensation circuit, for generating a modulation reference signal by combining the compensation signal and a parabolic A.C. modulation signal; anda modulation device, coupled to the horizontal scanning size control circuit, for generating a modulation voltage relative to the modulation reference signal and sending to a second end of the horizontal deflection yoke for compensating the variation of horizontal scanning size due to the effect of the anode load current.