2stageEF high performance class AB power amp / 200W8R / 400W4R

P.S.: spice models wanted for IXYS vertical mosfets:

  • IXTH80N20L (200V, 80A, 0.032Rdson)
  • IXTH48P20P (200V, 48A, 0.085Rdson)

OK, you took a leap and ordered some;) the least I can do is develop some models based on the specification data.
Maybe we can tune it later based on actual measurements.
It will take a little while, I need to study a bit, when are they due?

Best wishes
David
 
VI Limiters in Amplifiers

Not this test.
But this one does show the high voltage back emf when an inductive load is suddenly cut off.
The back emf peaks can be limited to just above the supply rails by adding in the output to supply rail protection diodes.

Test2 might be the same as I saw elsewhere.
They talk about reading the height of the scope pulse to arrive at the current limit set by the IV limiter.
 
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...
I wonder also if you have tried any of Bob C's suggestion of zobels in the gate leads as well as the series R's?
...

Toni, have you ever experimented with a Zobel from gate to source in lieu of a gate stopper resistor? As described by Cordell...

Yes, have used this RC snubbers with the EXC10[NP]20 to stop the oscillations. AFAIK there was a picture in this thread showing them. Helped a little bit but didn't cure the oscillations. Using the gate/drain snubbers may help to further decrease the gate resistors but I felt uncomfortable doing so.

BR, Toni
 
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SA2016: using vertical power mosfets from IXYS

IXYS power mosfets arrived today!
Fun for upcoming weekend! ;)

BR, Toni
 

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