October 2012

Doc ID 023526 Rev 1

1/20

AN4150

Application note

Power MOSFET technology gate current needs in a synchronous

buck converter

Introduction

High frequency converters and applications require the best driver-MOSFET trade-off in

terms of dynamic parameters to optimize the turn-on and turn-off transients. Power

MOSFET technology also plays an important role in minimizing dynamic losses and

improving system efficiency.

In this document, the full characterization of Power MOSFET gate current is realized by

technology on gate current behavior.

Ever increasing system switching frequency pushes designers and converter engineers to

optimize semiconductor technology, improving device switching behavior and system

efficiency. In fact, the higher the switching frequency, the larger the switching and dynamic

losses; in these conditions, the best trade-off between the driver and Power MOSFET is

mandatory to enhance the overall converter performance.

Power MOSFET gate current behavior during switching transients plays an important role in

establishing a good trade-off between Power MOSFET and driver performance.

In this document, Power MOSFET gate current characterization is performed through bench

converter, allowing a full understanding of the impact of the silicon technology on device

gate current.

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