Overcurrent protection circuit

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.