Patent ID: 7759920

Claim:
A switching regulator converting an input voltage input to an input terminal thereof to a prescribed substantially constant voltage and outputting the converted voltage from an output terminal thereof as an output voltage, the switching regulator comprising: a switching transistor performing a switching operation based on a control signal input to the switching transistor; an inductor charged by the input voltage based on the switching operation of the switching transistor; a control circuit unit performing a switching control of the switching transistor so that the output voltage output from the output terminal is substantially equal to the prescribed substantially constant voltage; a first ground terminal for connecting the control circuit unit to a ground potential; a second ground terminal for connecting the switching transistor to the ground potential; and a protection circuit unit for turning OFF the switching transistor to be electrically non-conducting regardless of a status of a control signal output from the control circuit unit when a disconnection between the first ground terminal and the ground potential is detected.