POWER FACTOR CORRECTING CONTROLLER FOR CONTROLLING VOLTAGE AND OPERATING METHOD OF POWER SUPPLY

摘要

PURPOSE: A power factor correcting controller for controlling voltage and an operating method of power supply are provided so that an improved power factor correcting can be achieved by the operation of a naturally commutated controller of a variable frequency or fixed off-time controller. CONSTITUTION: A power factor correcting controller for controlling voltage and an operating method of power supply include several devices. A reference voltage and bias elements(220) is used to a controller and then generates an inside reference voltage and bias for determining states of various outside signals(204). A mode detection and pulse width modulation element(206) determines that the controller operates at the fixed off-time mode or ZVS mode from an outside signal(204) and an inside reference(202) for providing a voltage output signal(234). A timing circuit(260) produces a fixed off time signal and voltage lamp signal(208) and these signals is used by the controller, thereby producing a double operating mode.