Diodes ZXGD3105N8 synchronous MOSFET controller

Enabling flyback power supply designers to replace inefficient Schottky rectifiers with a MOSFET driven as a diode, the ZXGD3105N8 synchronous MOSFET controller can achieve a standby power consumption for set-top boxes of less than 100 mW and full-load efficiencies greater than 87%.

Drawing a quiescent current of less than 1 mA and able to operate from supply voltages of 4.5, the controller delivers flyback power supplies capable of exceeding the Energy Star standby ratings.

The device can also operate at switching frequencies to 500 kHz, reducing transformer size.

To help maximise power circuit efficiency, the controller functions as a proportional gate drive that both protects against unnecessary MOSFET turn-off and reduces MOSFET turn-off propagation delay down to 15 ns, minimising reverse current flow.