RE: Series connection of Mosfets/IGBTs

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

Original poster: Greg Leyh <lod-at-pacbell-dot-net> 

The IGBT's we work with utilize the standard IGBT technology; that is they 
have a bipolar region [either PT or NPT] that is heavily influenced by the 
MOSFET body current.  They do not contain a string of devices in 
series.  All of the internal IGBT dies are in parallel, and all are rated 
for the full operating voltage.
IGBT's aren't limited by frequency per se, but more so by their maximum 
di/dt rating. So the max operating freq would be dependent on the peak 
current as well:

di/dt = Ipeak * 2pi * freq

And like many other bits of technology, prices are always coming down.



>Original poster: "Mccauley, Daniel H" <daniel.h.mccauley-at-lmco-dot-com>
>
>Yes Greg, but those HV IGBT's are basically just a series connection of
>single FETs anyways.
>Also, they (particularly the HV IGBTs) are still relatively low PRF type
>devices.  I don't believe
>you could get 300kHz operation out of them.
>
>Also, at the current price tag, they are well above the price range for
>most amateurs and there is slim
>chance they'll start showing up on EBAY anytime soon.