Patent ID: 6657840
Filing Date: 2003-12-02
Classification: H04N

Abstract:
A protecting circuit for a horizontal transistor used in a horizontal deflecting circuit of a cathode ray tube, the horizontal deflecting circuit comprising a horizontal driving circuit, a horizontal output circuit, and a S-character correcting loop, wherein a D.C. voltage is provided by a D.C. voltage source to the horizontal deflecting circuit, the horizontal output circuit comprises the horizontal transistor, the S-correcting loop comprises a main capacitor, a sub capacitor, and a controlled switch, the controlled switch is used for selectively connecting the sub capacitor and the main capacitor in parallel, the protecting circuit comprising:a switching circuit coupled to the controlled switch, the controlled switch electrically connecting the sub capacitor and the main capacitor in parallel when the switching circuit being on; and a power sensor coupled to the D.C. voltage source and the switching circuit, the power sensor detecting a status of the D.C. voltage source and controlling the switching circuit, wherein the power sensor turning on the switching circuit when the D.C. voltage source being substantially reduced.