CONTROL CIRCUIT OF POWER FACTOR CORRECTION CONVERTER OPERATING IN CRITICAL CONDUCTION MODE AND POWER FACTOR CORRECTION CONVERTER COMPRISING THTEREOF

摘要

The present invention relates to a control circuit of a power factor improving converter, which comprises: a current detection resistor for detecting voltage corresponding to current flowing through an inductor of the power factor improving converter; and a control unit for detecting disconnection of the current detection resistor based on the detected voltage, and controlling a main switch of the power factor improving converter to have a constant turn-on time for every preset period when the disconnection of the current detection resistor is detected. Therefore, the main switch and other elements can be prevented from being damaged for the disconnection of the current detection resistor.