| 摘要 |
PURPOSE: To provide an abnormal high voltage detection protecting device in which a normal operation is maintained and a protection function is attained with safety in a fault mode of a switching power supply when the supplied power of a high voltage generating circuit is increased and supplied power of the abnormal high voltage detection protecting device is decreased. CONSTITUTION: This abnormal high voltage detection protecting device is provided with a switching power supply circuit 1, a high voltage generating circuit use supply power line 2, a supply power line 3 for the abnormal high voltage detection circuit, a backup circuit 4, a high voltage generating circuit 8 and an abnormal high voltage detection protecting circuit 9. The backup circuit 4 is composed of a Zener diode 5 and a diode 6, and power is supplied to the abnormal high voltage detection protecting circuit 9 through the supply power line 2 for the high voltage generating circuit and the backup circuit 4. |
