Path: ...!news.snarked.org!xmission!usenet.csail.mit.edu!nntp.TheWorld.com!usenet.blueworldhosting.com!diablo1.usenet.blueworldhosting.com!nnrp.usenet.blueworldhosting.com!.POSTED!not-for-mail From: "Edward Rawde" Newsgroups: sci.electronics.design Subject: Re: LTSpice model for a SiC MOSFET Date: Wed, 21 May 2025 09:42:11 -0400 Organization: BWH Usenet Archive (https://usenet.blueworldhosting.com) Lines: 96 Message-ID: <100kl7l$30hs$1@nnrp.usenet.blueworldhosting.com> References: <100c4og$t4lo$1@dont-email.me> <100e4nq$1dhk3$1@dont-email.me> <9n8l2k9pc9jq3iichdq1baq04uqqk13ksg@4ax.com> <100epio$1h4ca$1@dont-email.me> <100ft5h$1s0j$1@nnrp.usenet.blueworldhosting.com> <100hb9s$24itl$3@dont-email.me> <100i0k2$ea0$1@nnrp.usenet.blueworldhosting.com> <100ibpi$2at8a$2@dont-email.me> <100if1h$tds$1@nnrp.usenet.blueworldhosting.com> <100jsf2$2n1hq$2@dont-email.me> Injection-Date: Wed, 21 May 2025 13:42:13 -0000 (UTC) Injection-Info: nnrp.usenet.blueworldhosting.com; logging-data="98876"; mail-complaints-to="usenet@blueworldhosting.com" Cancel-Lock: sha1:JN1/VuFUC6V3J2r6egv1FBs9QLk= sha256:F7gtUnsJa/ZnvL5Zqyq0jpEZT+01yLqSUZ+rsBcC8mw= sha1:d2DB6laGVQXAN1BAFkH+EcNXvmc= sha256:BzX294h98mBtPe5lNwlcGj7RYJLOhZCmyjbaz0WJgXc= X-Newsreader: Microsoft Outlook Express 6.00.2900.5931 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6157 X-Priority: 3 X-RFC2646: Format=Flowed; Response X-MSMail-Priority: Normal Bytes: 5772 "Bill Sloman" wrote in message news:100jsf2$2n1hq$2@dont-email.me... > On 21/05/2025 3:44 am, Edward Rawde wrote: >> "Bill Sloman" wrote in message news:100ibpi$2at8a$2@dont-email.me... >>> On 20/05/2025 11:38 pm, Edward Rawde wrote: >>>> "Bill Sloman" wrote in message news:100hb9s$24itl$3@dont-email.me... >>>>> On 20/05/2025 4:26 am, Edward Rawde wrote: >>>>>> "Bill Sloman" 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 >>>>>>>> wrote: >>>>>>>> >>>>>>>>> On 19/05/2025 12:15 am, john larkin wrote: >>>>>>>>>> On Sun, 18 May 2025 18:11:58 +1000, Bill Sloman >>>>>>>>>> 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". Does the word "hyperbole" mean anything to you Bill? A search engine should help. I don't mean (x^2)/(a^2)-(y^2)/(b^2)=1 > >> 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. > > > > -- > Bill Sloman, Sydney > >