Switch control device, power supply device comprising the same, and driving method of power supply device utilizing turn-on period half-on time point detection

摘要

The present invention relates to a switch controller, a power supply including the same, and a method for driving the same. An AC input of the power supply is connected to a rectification circuit. The power supply includes a power switch to which an input current passed through the rectification circuit flows during an on-period and a switch controller, the switch controller detects a half-on time point that is the intermediate time point of the on-period, detects a sense voltage that is determined by a current flowing to the power switch during the on-period at the half-on time point, generates a modulation wave by controlling a reference wave according to the detected voltage, and controls switching operation of the power switch according to the modulation wave.

主权项

1. A power supply comprising:
a rectification circuit configured to be coupled to an AC input and generate an input voltage and an input current; a power switch configured to receive the input current from the rectification circuit during an on-period; and a switch controller configured to:
detect a half-on time point that is a half time point of the on-period;detect a sense voltage based on a current flowing to the power switch during the on-period at the half-on time point;generate a modulation wave based on a reference wave and the detected sense voltage; andcontrol switching operation of the power switch based on the modulation wave.