| 摘要 |
PURPOSE: To protect the television receiver from an excessive alta voltage to generate X-rays by generating a signal used to prevent production of switching and to reduce an output voltage on the occurrence of a 3rd signal generated when a frequency transition edge is lost. CONSTITUTION: On the occurrence of a fault state, a high voltage protection circuit 301 generates an inhibit signal 301a and inactivates a signal OH. On the other hand, s signal O32 H is generated even on the occurrence of the fault and a pulse DHa is generated at an output terminal 61a of a monostable multivibrator 61 even when the signal OH is inactivated as a result of the operation of a frequency divider circuit 45, a ramp wave generating circuit 37, a comparator circuit 38 and a flip-flop 61, and given to a base electrode of a transistor (TR) Q2 via a resistor 302 and when an alter voltage U exceeds a predetermined permissible level, production of the signal DH is prevented. When the signal OH is inactive by a protection circuit 301, a flip-flop 303 keeps the TR Q2 nonconductive. Thus, the production of the alta voltage U is prevented. |
