| 摘要 |
Provided is a solenoid drive circuit for suppressing a response delay caused by a surge voltage. The solenoid drive circuit (10) is provided with: a solenoid coil (11) which performs a plunger suction-attachment operation; a bidirectional Zener diode (40) which is connected in parallel to the solenoid coil (11) and absorbs, up to a Zener voltage, the surge voltage generated when the power supplied to the solenoid coil (11) is stopped; and a holding transistor (32) which is connected in series to the solenoid coil (11) and the bidirectional Zener diode (40). When a power supply voltage is applied, the holding transistor (32) turns on and a conduction path for the solenoid coil (11) is thereby formed. In this structure, the surge voltage reduced to the Zener voltage by the bidirectional Zener diode (40) is applied to the holding transistor (32). |
