Patent ID: 8270138

Claim:
A threshold adjustment method for a power supply controller having an overcurrent protective function provided for performing a first shutoff operation for a semiconductor switching element, disposed on a power supply line from a power source to a load, for a first reference time if a load current passing through said semiconductor switching element exceeds a first threshold, and thereafter restoring said semiconductor switching element to a conductive state, said threshold adjustment method for the power supply controller comprising: decreasing a level of said first threshold with time if a current supply detection signal is outputted from a current supply detecting circuit configured to detect current supply on said power supply line; and performing an initialization operation at most a predetermined number of times, the initialization operation restoring said first threshold to an initial level if said first shutoff operation for said semiconductor switching element is performed due to said overcurrent protective function being performed, and after the level of the first threshold is decreased, determining if the load current passing through the semiconductor switching element exceeds a decreased value of the first threshold.