Reverse voltage across IGBT

Well, you can get IGBT's with internal body diodes. ;) That's what I got...

I don't remember if the IGBT structure behaves like a MOSFET or a BJT overall. A MOSFET has an intrinsic body diode (since the substrate is tied to source), although it isn't necessarily rated for duty. An IGBT is often mentioned as a MOSFET + BJT "Darlington", in which case the big part would act like a BJT, no?

On a related subject, what happens when you reverse-bias a generic power transistor, 2SC2625 for example? (800V 10A, I think, NPN power transistor used in computers the world around for a good decade or so.) Obviously the C-B junction gets forward-biased, which will tend to pull the base down as well. But then, current starts diffusing through from the emitter, no? How much current would this withstand, would it be comparable to Ice(max)?

Tim

-- Deep Fryer: a very philosophical monk. Website:

Let's say that due to whatever, there is momentary reverse voltage across the IGBT. Just what levels are actually harmful? My IGBT is of the 1,200 V rated variety. I am not sure how reverse voltage can damage an IGBT.

Not yet... But I do not want to.

You'll have to consult your IGBT's datasheet, but... Typically with the gate at zero volts, reverse collector emitter breakdown will occur nearish

Some IGBTs have a reverse avalanche energy specification. Apparently avalanche rated devices can successfully survive reverse avalanche events provided certain requirements are met (such as maximum avalanche energy is not exceeded). This particular feature doesn't seem to be too well characterized, as far as I can tell.

This document:

Mentions the effect a couple of times briefly in sections 8.2 and 8.4.