Patent ID: 8325451

Claim:
A power switching circuit comprising: an output transistor connected between a power supply terminal and an output terminal; an output controller which controls a conducting state of the output transistor according to an input signal, wherein the output controller comprises a delay circuit which delays the input signal, a NAND circuit which outputs a NAND operation result of a short circuit control signal and the input signal input via the delay circuit as an evaluation signal, an AND circuit which outputs an AND operation result of the evaluation signal and the input signal as an enable signal and a charge pump circuit which outputs an output control signal for controlling a conducting state of the output transistor according to the enable signal; a sense transistor having a gate commonly connected to the output transistor, which detects an output current flowing into the output transistor; an output current detection terminal in which a detection voltage corresponding to the output current is generated; a short circuit detector which detects a short circuit condition of the output current detection terminal according to the detection voltage and outputs a short circuit control signal for stopping the output transistor or limiting the output current, wherein the short circuit detector includes a comparator which compares the detection voltage and a first reference voltage and outputs a comparison result as the short circuit control signal; and the output controller cuts off the output transistor irrespective of the input signal if the short circuit control signal indicates that a short circuit is detected.