Power Sources and Supplies: World Class Designs

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Chapter 7

7.5 Power MOSFETs

7.5.1 Introduction

Compared to BJTs, which are current controlled devices, fi eld effect transistors are

voltage controlled devices. There are two basic fi eld-effect transistors (FETs): the

junction FET (JFET) and the metal-oxide semiconductor FET (MOSFET). Both have

played important roles in modern electronics. The JFET has found wide application in

such cases as high-impedance transducers (scope probes, smoke detectors, etc.) and the

MOSFET in an ever-expanding role in integrated circuits, where CMOS (complementary

MOS) is perhaps the most well-known.

Power MOSFETs differ from bipolar ...