Method and apparatus reducing overshoot in a power supply controller

摘要

A power supply controller with reduced overshoot at the power supply output during start up. In one embodiment, a power supply controller for a switched mode power supply includes a drain terminal to be coupled to a primary winding of a power supply transformer, a source terminal to be coupled to ground and a control terminal. The control terminal is to be coupled to provide bias supply power to the power supply controller and receive a feedback current from the power supply output. The control terminal is also to be coupled to an external capacitor to provide power to the power supply controller during normal operation. The power supply controller includes a charging circuit and a logic circuit to maintain the voltage at the control terminal at a control terminal regulation voltage during start up.