To provide an inexpensive storage charge discharging circuit which safely and stably operates by constituting, so that a power source output terminal intended to start up earliest starts up earlier even if the start-up occurs at any timing due to momentary interruption, in a power supply unit having a plurality of power supply output terminals in which start-up sequence speeds to reach an output voltage value are different from each other.

A partial pressure resistance is connected with the power supply output terminal that falls earliest and starts up latest in the power supply unit. In an npn transistor Q1, a base thereof is connected with a divided voltage, an emitter thereof is connected with a GND, and a collector hereof is connected with the power supply output terminal that has been kept stable until the last, respectively through a resistance R5. In an npn transistor Q2, a base thereof is connected with the collector of Q1, an emitter thereof is connected with the GND, and a collector thereof is connected with the power supply output terminal to be discharged, respectively through a resistance R6. Therefore, even if momentary interruption in any term occurs, the power supply output terminal to start up earliest can start up earliest.

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