POWER CONVERTER AND DRIVING METHOD THEREOF

摘要

A power converter and a driving method thereof are provided to simplify a structure of an SMPS(Switching Mode Power Supply) by detecting a valley point of the switch voltage without using an additional input and output terminal. A power supply unit(100) includes a primary coil(L1) of a transformer and a switch(M1). An input voltage is inputted to the primary coil of the transformer. The switch has a control electrode, a first electrode, and a second electrode. The second electrode is connected to the primary coil of the transformer. An output unit(200) includes a second coil(L2) of the transformer. The output unit outputs the output voltage transformed by the transformer. A PWM(Pulse Width Modulation) controller(300) receives the sensing voltage corresponding to the switch current flowing between the first electrode and the second electrode and the feedback voltage corresponding to the output voltage and detects the valley point of the switch voltage between the first electrode and the second electrode.