HIGH VOLTAGE POWER SUPPLY CIRCUIT

摘要

PROBLEM TO BE SOLVED: To prevent the response of the circuit against a sudden change in a load of a CRT from being deteriorated by quickening a rising time of the CRT when a power switch of a monitor is closed. SOLUTION: A high speed processing circuit 10 connects to a detection line 6 through which a feedbacks signal is fed from a high voltage detection circuit 5 to a high voltage stabilizing circuit 1, a pnp transistor(TR) 12 of the high speed processing circuit 10 is conductive to connect a resistor 11 connecting to the detection line 6 to ground so as to forcibly decrease a detected high voltage. Thus, the high voltage stabilizing circuit 1 allows a resonance power supply circuit 2 to increase a peak level of a flyback pulse as a higher pulse voltage so as to quicken a rising time of the high voltage output fed to an anode of a CRT. When a voltage across a capacitor 13 charged via a resistor 14 is nearly higher than a voltage at a point A after the lapse of a prescribed time, the pnp TR 12 is non-conductive and the resistor 11 is disconnected from ground and then a sudden change of a load of the CRT does not slow down the response of the circuit.