POWER SUPPLY SWITCH

Abstract

A power supply circuit includes a capacitor connected in parallel to a power supply, a processor, and a voltage divider circuit configured to divide an input voltage from the power supply and output the input voltage to the processor. The voltage divider circuit includes a first sensing resistor connected to the power supply, a second sensing resistor connected in series with the first sensing resistor, a discharge resistor connected to the power supply, and a voltage divider resistor connected in series with the discharge resistor, having a lower resistance value than the discharge resistor.The processor is configured to determine whether an abnormality has occurred in the voltage divider circuit, based on a first voltage and a second voltage, respectively, input from a first junction point between the first sensing resistor and the second sensing resistor, and from a second junction point between the discharge resistor and the voltage divider resistor.

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