looking for high voltage mosfet

[Tolstoy]

Hi all, I've looked around but haven't had any luck finding a logic
level n-channel mosfet rated around 400 volts Vds. I have bought
automotive coil driver logic level IGBT's before, but this time I'd
like to use mosfets.
The mosfet needs to turn hard on at six volts and conduct several
amps. I'd like to get Rds around a tenth of an ohm; I'll parallel
them if I have to.

 

[Ray King]

Hi,

I think Motorola was the only 5v logic 400v fet. Most folks use an IC ( TTL
5 voltage to 12v out put 4730 ? )or an npn in the common base mode. Drive
the emitter from 5v ( 1k in the base to the 5v supply ) the collector with a
resistor pull-up to 12v. A buffer on the output is a good idea.
Ray



I think it wou

 

[Lostgallifreyan]

Most folks use an IC ( TTL
5 voltage to 12v out put 4730 ? )or an npn in the common base mode.
Drive the emitter from 5v ( 1k in the base to the 5v supply ) the
collector with a resistor pull-up to 12v. A buffer on the output is a
good idea.

Or something from "The Best Of EDN". (One of my favourite ideas of all.)

Try an n-channel JFET, gate to common ground, pull-up resistor on the
drain to 12V, input to the source. Anything over 1 to 2V input should be
fine. This single FET (and pullup resistor to 12V or so) will make a non-
inverting level translator to give you the volts needed by the MOSFET. I'm
assuming that your positive turn-on voltage means you're using an
enhancement mode FET, so if not, this idea will need rethinking.