| 摘要 |
PROBLEM TO BE SOLVED: To make use of an overvoltage protection circuit to simplify a circuit, and make it possible to restart even if the off time is short. SOLUTION: A power supply contains a power circuit 1 that produces output to a computer and the like; a power on/off control circuit 2; and an overvoltage protective circuit 2 that detects overvoltage in power supply output and stops the operation of the power circuit. The power supply is also provided with a circuit IC 2 that supplies the overvoltage protection circuit 3 with auxiliary power A through an auxiliary power circuit 21 when a switch SW1 for operating an a.c. power supply relay SSR1 is turned on. Further, it is provided with a circuit PC1, R4 that operates the overvoltage protective circuit 3 according to a power supply off signal. When a power supply off signal is input, the overvoltage protective circuit 3 is actuated through the PC1, R4 to turn off power. To restart, the SW1 is turned off and the power supply A to the overvoltage protective circuit is turned off. Overvoltage protective operation is thereby stopped, and then the SW1 is turned on. |
