The MP9989 is a fast turn-off, intelligent rectifier for flyback converters that integrates a 100V MOSFET. It can replace a diode rectifier for higher efficiency and power density. The chip regulates the forward voltage drop of the internal power switch to 40mV and turns off before the drain-source voltage reverses. The MP9989 can generate its own supply voltage without the need for auxiliary winding, which makes it suitable for charger applications with a low output voltage requirement or any other adaptor applications with high-side set-up. The internal ringing detection circuitry prevents the MP9989 from falsely turning on during discontinuous conduction mode (DCM) or quasi-resonant operations.