Offline Quasi-Resonant PWM Controller

The FAN602F is an advanced PWM controller aimed at achieving power density of ≥10W/in³ in universal input range AC/DC flyback isolated power supplies. It incorporates Quasi-Resonant (QR) control with proprietary Valley Switching with a limited frequency variation. QR switching provides high efficiency by reducing switching losses while Valley Switching with a limited frequency variation bounds the frequency band to overcome the inherent limitation of QR switching. FAN602F features mWSaver® burst mode operation with extremely low operating current (300 µA) and significantly reduces standby power consumption to meet the most stringent efficiency regulations such as Energy Star’s 5-Star Level and CoC Tier II specifications. FAN602F includes several user configurable features aimed at optimizing efficiency, EMI and protections. FAN602F has a programmable switching frequency range that provides flexibility in choosing noise rejection in targeted frequency zones. It incorporates user-configurable minimum peak current, which allows controlling the burst mode entry/exit power level, thereby enhancing light-load efficiency and eliminating audible noise. It also includes several rich programmable protection features such as Over-Voltage Protection (OVP), precise constant output current regulation (CC) and Over-Temperature Protection (OTP) through external thermistor.