Patent ID: 8547676

Claim:
An overcurrent protection device for protecting a load-driving circuit having a DC power supply, an electronic switch, an electric wire and a load from an overcurrent, the overcurrent protection device comprising: a voltage detection unit which is configured to detect an output voltage of the DC power supply; a clock unit which is configured to clock an elapsed time after turning the electronic switch on; a switch control unit which is configured to turn the electronic switch off when the output voltage of the DC power supply reduces to a value equal to or lower than a threshold voltage set in advance and to turn the electronic switch on again when a predetermined standby time elapses; a standby time determining unit which is configured to randomly determine the predetermined standby time when the output voltage reduces to the value equal to or lower than the threshold voltage and the electronic switch is caused to be turned off, and a count unit which is configured to count a number of occurrence of a fact that a required time until the output voltage of the DC power supply reduces to the value equal to or lower than the threshold voltage from the turning-on of the electronic switch is equal to or smaller than a preset threshold time, wherein the switch control unit is configured to hold the turned-off state of the electronic switch irrespective of elapse of the predetermined standby time when a count value by the count unit reaches a predetermined count threshold value.