Insulated gate bipolar transistor

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A power IGBT

Cross section of a typical IGBT. Please note that an IGBT is usually constituted of many paralleled cells and that dimensions are not to scale.

Static characteristic of an IGBT.

The Insulated (sometimes called Isolated) Gate Bipolar Transistor is a Power semiconductor device that combines the simple gate drive characteristics of the MOSFETs with the high current and low saturation voltage capability of bipolar transistors by combining an isolated gate FET for the control input, and a bipolar power transistor as a switch, in a single device. The IGBT is mainly used in switching power supplies and motor control applications.

The IGBT is a recent invention. The "first-generation" devices of the 1980s and early '90s were relatively slow in switching, and prone to failure through such modes as latchup and secondary breakdown. Second-generation devices were much improved, and the current third-generation ones are even better, with speed rivaling MOSFETs, and excellent ruggedness and tolerance of overloads.

The extremely high pulse ratings of second- and third-generation devices also make them useful for generating large power pulses in areas like particle and plasma physics, where they are starting to supersede older devices like thyratrons and triggered spark gaps.

Their high pulse ratings, and low prices on the surplus market, also make them attractive to the high-voltage hobbyist for generating large amounts of high-frequency power to drive experiments like Tesla coils.

Availability of affordable, reliable IGBTs is a key enabler for electric vehicles and hybrid cars. Toyota's second generation hybrid Prius has a 50 kW IGBT inverter controlling two AC motor/generators connected to the DC battery pack.

In addition, for about 20 years Toshiba has applied IGBTs as audio amplifiers.^{[citation needed]}