Patent ID: 8441767

Claim:
An overcurrent protection circuit comprising: a load driver configured to drive a load; a controller configured to turn ON and OFF the load driver in accordance with an input condition; a current sensor configured to measure a load current flowing through the load; and an add/subtract circuit configured to perform an addition operation on a previous calculation result or a subtraction operation on the previous calculation result so as to produce a present calculation result, the addition operation using a predetermined added value that depends on the presently measured current, the subtraction operation using a predetermined subtracted value that depends on the presently measured current, wherein the add/subtract circuit performs the addition operation when the presently measured current is greater than a predetermined current value, the add/subtract circuit performs the subtract operation when the presently measured current is less than the predetermined current value, and the controller turns OFF the load driver, when the present calculation result of the add/subtract circuit exceeds a predetermined first determination value.