Re: The OLTC IGBTs

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi Ken,

MicroSim does not have a nice IGBT model (free version) so I fake a few
things in the MicroSim schematics.  I am using a switch in the models that
is working like an IGBT.

IGBTs work just like transistors for CE stuff.  You can get IGBTs with or
without the big anti-parallel diodes in them.  There are actually two die
in the package in that case.  The data sheet for my IGBTs is at:

http://hot-streamer-dot-com/temp/irg4pf50wd.pdf

FETs have "intrinsic" diodes due to their design.  I am not sure if that is
true of IGBTs.  If IGBTs do have a "natural" diode in them, no one uses it.
 They either use snubber circuits or add a big diode external to the IGBT
(but in the same plastic package.

Cheers,

	Terry




At 01:36 PM 8/28/2002 -0700, you wrote:
>I've just put together 3 things I've noticed:  1) Terry's schematics
>don't show any "catch" diodes across the IGBTs (unless I missed them); 2)
>The IGBT data sheets I happen to have don't show intrinsic (substrate)
>diodes e.g. in MOSFETs and the max. reverse collector-emitter voltage is
>listed as some 18 V; and 3) I recall a remark in an app. note that IGBTs
>didn't have them.  Did I miss them, or are they needed?
>
>Ken Herrick
>