POWER SUPPLY CONTROLLER AND POWER SUPPLY CONTROL METHOD

摘要

PROBLEM TO BE SOLVED: To cancel a rush current while shortening a period for stopping the operation of a protective function for abnormal current in a semiconductor element with built-in temperature sensor as much as possible. SOLUTION: A timer circuit 1 counts up time required from turning off a switch SW1 up to turning on the switch SW1 again and supplies the timer information to a mask signal generation circuit 2. The level of a rush current is changed in accordance with time from the OFF operation of the switch SW1 up to the ON operation of the switch SW1. Therefore the circuit 2 changes the duty ratio (pulse width) of a mask signal and supplies the changed duty ratio to the '-' input terminal of a comparator CMP1. Consequently the rush current can be canceled while shortening the operation stop period of the protective function for the abnormal current in the semiconductor element AQ with built-in temperature sensor as much as possible.