200V N-channel FET 200V with nsec speed?

Hello Tom,

There is already some inductance ;-)

I did already suggest push-pull which would remedy a lot of problems. Hopefully the engineers there will warm up to that idea because it makes life easier.

Those are generally too low in breakdown voltage. The option is, of course, push-pull with a step-up transformer. For that scenario we'd already have the right FETs.

--
Regards, Joerg

http://www.analogconsultants.com

Hello Robert,

Or employ a fast clamp that charges up a capacitor, then use the cap as a "kicker".

--
Regards, Joerg

http://www.analogconsultants.com

Hello Robert,

It has poor tdoff and tf (>>10nsec), plus we'd need to parallel about ten of them which drives the capacitances to uncomfortable levels. Infineon does have some newer nice devices but I am a bit hesitant with that manufacturer after they weren't able to get samples of their BSP297 to us. Despite the fact that I told them we'd pay whatever it takes to get them across the ocean and almost two hours on the phone :-(

--
Regards, Joerg

http://www.analogconsultants.com

Look at ST Micro STN1N20 or STQ1NC45R-AP.

When I was working on ground penetrating radar we discovered several things most of which are still true today. The on and off times are as per test circuit and not absolute limits of the device. Many devices could sustain larger than specified gate voltage overdrive. Caveat here, our duty cycle was low. Often unspecified Internal Source Inductance was the unwelcome wall.

--

    Boris Mohar

Hello Robert,

Thanks. Whatever they mean with crossover time is a bit long but we'll order some.

This one is a bit slow but as Win hinted one has to take that data with a grain of salt. So, we'll order some of these as well.

--
Regards, Joerg

http://www.analogconsultants.com

I've been casting about for fast MOSFETs too (though I can live with

100V but need 10W or so dissipation rating) and found that Infineon's OptiMOS series looks quite promising. But nobody seems to stock much of what is supposedly available !

Steve

Hello Steve,

That's just the problem. They do not seem to understand how electronic parts are marketed. By now I believe it would take some high-level management changes over there to correct that problem. Then their sales will probably increase, big time. They need some execs who pound the pavement and regularly do spot-check visits on clients large and small. Just to feel the pulse. That's what we did in our med biz and the CEO expected it from us.

--
Regards, Joerg

http://www.analogconsultants.com