POWER SUPPLY, CONTROL IC THEREFOR AND CONTROL METHOD THEREOF

摘要

PURPOSE: A power supply device, a control integrated circuit and control method thereof are provided to reduce a leakage current by forming elements for the control of the power supply device as one integrated circuit. CONSTITUTION: A first controller(200) operates a PWM control IC in the state of connecting an output terminal and a load. A second controller(300) determines the operation of the PWM control IC according to the voltage variation of a subsidiary capacitor connected to the first controller in the state of not connecting the output terminal and the load. A constant voltage circuit unit(500) supplies a constant voltage to the first controller and the second controller according to the operation state of the PWM control IC. [Reference numerals] (500) Constant voltage circuit unit; (800) PWM control IC; (810) DC/DC converter