Patent ID: 7355830

Claim:
An overcurrent protection device for protecting a main switch of a switching regulator from an overcurrent, the switching regulator supplying a current to a load circuit via the main switch and a rectifier switch which are cyclically turned on and off by a control signal, comprising: a judging unit operable to make a judgment whether the overcurrent is flowing through the main switch; a controller operable to turn off the main switch when the judging unit judges that the overcurrent is flowing through the main switch; a first prohibiting unit operable to prohibit the controller from turning off the main switch during a first time period following after the control signal being output to instruct the controller to turn on the main switch; an edge pulse generator operable to detect an edge of an input signal of the rectifier switch, and output a prohibition signal during a second time period following after the main switch being turned on; and a second prohibiting unit operable to prohibit the controller from turning off the main switch by providing the prohibition signal wherein the second time period starts at or before an end of the first time period, and the first time period ends before an end of the second time period.