On Sat, 22 Sep 2012 23:52:57 +0000 (UTC), supervinx
put finger to keyboard and composed:

Well, I made some more measurements.
The IRFPE40 shows the following voltages:
VDS=312V (max. 800V)
VGS=0 (?????)

What's the IRFPE40 function ?
Looking at the PCB it seems that the 3844 supply voltage comes from it...

I would expect that the MOSFET is the chopper. Its gate would be
driven by the UC3844 PWM controller.

- Franc Zabkar
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