APPARATUS FOR SWITCHING MODE POWER SUPPLY DETECTING THE AC-OFF STATUS

摘要

The present invention relates to a power supply apparatus for sensing an AC-off state. The present invention includes: a rectifier which rectifies AC power into DC power; a transformer which converts the voltage of the DC power rectified from the rectifier and supplies an output voltage; and a PWM control module which controls the output voltage by switching a power switching element connected to the transformer, operates the power supply apparatus by connecting the power of an HV pin to a VCC pin, and determines an AC-off state by sensing the voltage rectified from the rectifier. The present invention senses the AC-off state more accurately and minimizes possibility of abnormal operation by allowing the power supply apparatus to operate normally after sensing the AC-off state through the voltage rectified from a wave rectifier and resetting operation power of the power supply apparatus.