SWITCHING MODE POWER SUPPLY AND THE DRIVING METHOD THEREOF

摘要

A switching mode power supply and a driving method thereof are provided to secure stable driving by preventing screen noise due to a ripple and damage of an element due to transient power. A switching mode power supply includes a power supply unit(100) and a PWM(Pulse Width Modulation) signal generation unit(600). The power supply unit includes a first switching element(QSW) and supplies power to second and third coils of a secondary side(200) of a transformer according to operation of the first switching element. The first switching element is coupled to a first coil(L1) of a primary side of the transformer for converting an input voltage(Vin). The PWM signal generation unit controls on/off of the first switching element by receiving a feedback voltage(Vfb), a sensing signal(Vsense), and a third voltage.