This Application Note compares the MOSFET to its more known and more used relative, the bipolar transistor. It shows the major advantages the MOSFET has over the BJT as well as some trade-offs. The most important conclusion is that overall circuit efficiency is application-specific; one has to closely estimate the balance of conduction and switching losses under all operating conditions and then decide on the device to be used: a regular bipolar or a MOSFET—or maybe an IGBT.

For more information on power MOSFETs, visit Microsemi’s Web site.