AN4150 Datasheet, PDF (1/20 Pages) STMicroelectronics – Power MOSFET technology gate current needs in a synchronous buck converter

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
bench tests and OrCAD^® simulation results, focusing on the impact of Power MOSFET
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
tests and simulations (by Cadence^® OrCAD Capture) on a single-phase synchronous buck
converter, allowing a full understanding of the impact of the silicon technology on device
gate current.
October 2012
Doc ID 023526 Rev 1
1/20
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