| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an overcurrent protection circuit that is superior in responsiveness and moreover, is further low in power consumption and small in size. <P>SOLUTION: In the overcurrent protection circuit 10, a power supply line 16 connects an input terminal 12, to which main supply voltage Vcc is applied and an output terminal 14, to which a load circuit 100 is connected. This power supply line is provided therein with a semiconductor switch circuit 18 that turns on/off the power supply line 16 and a current detection circuit 20, that detects a driving current Ia that has passed through the power supply line 16. The current detection value Ia from the current detection circuit 20 is supplied to a control circuit 22. Here, the control circuit 22 controls the semiconductor switch circuit 18, based on the current detection value Ia. Hence, the overcurrent protection circuit uses FET as the semiconductor switch circuit 18, and its power consumption and size can be reduced, as compared with cases where, for example, a mechanical relay is adopted. By turning the semiconductor switch circuit 18 on/off based on the result of the detection of drive current Ia, high responsiveness can be obtained. <P>COPYRIGHT: (C)2008,JPO&INPIT |
