Re: LTSpice model for a SiC MOSFET

On 21/05/2025 3:44 am, Edward Rawde wrote:

"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:100ibpi$2at8a$2@dont-email.me...

On 20/05/2025 11:38 pm, Edward Rawde wrote:

"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:100hb9s$24itl$3@dont-email.me...

On 20/05/2025 4:26 am, Edward Rawde wrote:

"Bill Sloman" <bill.sloman@ieee.org> wrote in message news:100epio$1h4ca$1@dont-email.me...

On 19/05/2025 1:38 pm, john larkin wrote:

On Mon, 19 May 2025 12:23:54 +1000, Bill Sloman <bill.sloman@ieee.org>
wrote:
>

On 19/05/2025 12:15 am, john larkin wrote:

On Sun, 18 May 2025 18:11:58 +1000, Bill Sloman <bill.sloman@ieee.org>
wrote:
>

I'm looking at a problem where somebody wants to step down a 1kV low
current source to 3.3V.
>
The Baxandall class-D oscillator could do it, but it needs a pair 1.7kV
MOSFETs for the job. The Infineon SiC IMH170R450M1 would do it - though
it's a much higher current part (10A) than the job needs (about 1mA).
>
I've dived into the Infineon rabbit-hole which promises LTSpice models,
but wasn't able to find one.
>
Does anybody know of a similar - ideally cheaper and smaller - part for
which there is an LTSpice model?

>
I use a Cree/Wolfspeed 1200v part, C2M0280120D, in my Pockels Cell
driver.
>
https://www.dropbox.com/scl/fi/5arhyamrp0bl3tgb2fasn/DSC02771.JPG?rlkey=3ttcc2yt6s9nrtdouuv3aneol&raw=1
>
They do have an LT Spice model library that works.
>
Gate drive for SiC parts is a bear. I did it myself, but I think there
are chips for that now.
>
There are multi-kilovolt silicon mosfets too.
>
Baxandal looks to be inefficient and expensive as a low power
converter. The drain swing is 2x the supply voltage, and it needs two
fets and a difficult custom transformer.

>
It isn't going to be inefficient. That configuration is famous efficient.
>
The drain swing is actually 1.67 times the supply voltage, but it does
need two switching devices and a specially wound transformer (and we
know how reluctant you are to design them or get them made).
>
It is probably going to be too expensive for the application, and we'd
be grateful for your insights into a cheaper alternative. I can't think
of one.

>
I'm not sure what the specs are, but I have a few ideas.
>
One could make a flyback converter with a high-ratio transformer.
Coilcraft makes some, capacitor charging transformers and CCFLs. There
must be crazy cheap Indian or Chinese CCFL transformers.
>
ST makes a 1400v NPN transistor for under a dollar.

>
But you can't be bothered to post the part number.

>
What you should have said is that you couldn't be bothered to use a search engine.

>
I need at least 1.7kV. A 1400V part isn't interesting.

>
Centuries ago they'd put two transistors in series in the TV horizontal deflection department because a single one didn't have
enough Vce max.

>
The transistor was invented in the 1950's. Decades ago is closer to the mark.

 LOL sane people would have known what I meant without needing to point that out Bill.

Sane people don't say "centuries" when they mean "decades".

In any case there was no transistor capable of doing horizontal deflection and EHT  for a 20 or more inch CRT before the late 60s.
My father was never without a spare PL36.

So what.
<snip>
--
Bill Sloman, Sydney