PROTECTIVE DEVICE OF TELEVISION RECEIVER

摘要

PROBLEM TO BE SOLVED: To prevent a television receiver from smoking and catching a fire beforehand by completely stopping the operation of a switching power circuit when there is the possibility that overcurrent is caused to flow due to short circuit to bring about secondary damage in another circuit and when the switching power supply continues an intermittent oscillation operation resulting from an overcurrent limiting circuit operation. SOLUTION: Pulse voltage outputted from a flyback transformer 15 is inputted to a microcomputer 13. When the pulse voltage deviates from a set value that has been set beforehand by the microcomputer 13 due to short circuit and intermittent oscillation of the switching power circuit, the microcomputer 13 is made to output a signal for turning off a power supply relay 7 to stop power supply to the power circuit. COPYRIGHT: (C)2004,JPO&NCIPI