摘要 |
<p>Improvements to a power supply backup circuit used to backup the operation of a radio device or the like when a power supply therefor is interrupted. A reverse current preventing diode is connected such that its anode is connected to the junction point of a DC power source and a voltage stabilizing circuit, and a cathode connected to the stabilizing circuit. A transistor is provided which has a collector connected to the cathode of the diode, an emitter connected to one end of a capacitor the other end of which is grounded, and a base connected to a DC power source via a first resistor, and which has a second resistor connected across the base and emitter thereof. A third resistor is further connected across the collector and emitter of the transistor.</p> |