| 摘要 |
PURPOSE:To prevent surge current at the time of recovery from instantaneous power interruption, reclosing of input switch, or slow closing/opening with a predetermined time interval. CONSTITUTION:The surge current preventing circuit comprises a surge current preventing resistor 3 inserted into an input line connected with an input switch 2 which is connected with a power supply 1, a switch element 4 connected in parallel therewith, a capacitor 13 controlling the switching of the switch element according to the power supply voltage and further controlling the switching timing thereof thus constituting a switch element driving circuit, and a transistor 14 for short-circuiting the capacitor upon turn ON. The surge current preventing circuit further comprises a monitor circuit for comparing the divided power supply voltages to perform ON/OFF control of the transistor 14, and a capacitor 22 provided in the monitor circuit in order to control the output timing of the monitor circuit. |
