| 摘要 |
PROBLEM TO BE SOLVED: To provide a power supply circuit with a short determining mechanism effective in the integration and improvement of determination accuracy. SOLUTION: The power supply circuit 10 converts power by controlling a switching element SW disposed between a power supply source 100 and a load 102, and is provided: with a clock generating circuit 19 for generating a clock signal as the control timing of the switching element, a PWM circuit 14 for controlling the switching element based on the clock signal; an OCP circuit 16 for detecting the value of a current flowing from the power supply source to the load, and generating an overcurrent pulse in synchronization with the clock signal when the current value is a predetermined value or larger; and a short determining circuit 18 for determining the short circuit of the load by counting the number of the overcurrent pulses generated by the OCP circuit. The PWM circuit controls the switching element based on the overcurrent pulses generated from the OCP circuit and the determined result from the short determining circuit. COPYRIGHT: (C)2005,JPO&NCIPI
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