A 25 V synchronous MOSFET controller for notebook and laptop power supply designs of 90 W and above enables the replacement of inefficient Schottky diodes in flyback converters.
The ZXGD3104N8 is claimed to increase power supply efficiency by up to 3.5% through a reduction in rectifier losses of up to 70%. As a result, the device helps power supplies more easily attain the 87% Energy Star V2.0 rating.
With its wide operating voltage range of 5 to 25, this SO8 packaged MOSFET controller can be directly powered from the adapter’s 19 V supply rail while ensuring sufficient headroom if there is a transient overvoltage.
Combined with the device’s direct 180 V MOSFET drain-sense capability that eliminates the need for an external clamp circuit, designers can reduce component count.
The device’s proportional gate-drive operation guards against premature MOSFET turn-off as the drain current decays, thereby maximising circuit efficiency and ensuring body diode conduction losses are minimised.
