Sorry, no schematic, I'm contemplating switching a 90v, 3A DC motor.
I have a FGA25N120 IGBT, which I thought was the choice, but
now I'm not sure...

Is this part okay, or recommendations?

 

hi H,
Here is the datasheet.
A schematic would help.
E

 

I've read a million datasheets, but I've lost confidence what I'm looking at.
I thought I would make a simple switch with an IGBT, since they're the greatest
thing since sliced bread.

Um, okay, I found it, the graph all the way down, page 5,
SOA Characteristics:

And it won't let me copy and past it. Anyway, at 1200v, it will
switch .01A, and at 10v maybe 30A, continuous. And 90v?
Perhaps 3.5A.

Too close for comfort.

 

You can of course use this transistor, but the dissipated power on the transistor will be approx. 5 watts. If you apply the MOS transistor, then you can dissipate a transistor less than a fraction of a watt (for example: P=Ron*Id=10mOhm*3A=30 mW). Do not forget to shunt the motor in parallel with a diode, or even your transistor will break.

 

hi H,
Did you see the Vgs threshold voltage for that MOSFET.?
How do you plan to drive the Gate.?
E
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