Yes I was thinking also many times about this and came to the conclusion that it was possibly not well expressed......
Mr. Pass did you write this?
It is an error by someone else.
What puzzles me is the word "gain" in "stabilizing gain and bias". I do not understand what is being stabilized or possible mechanisms to perform the stabilization.
The circuitry is push-pull complementary. If you build such a thing with no
degeneration, you contend with high variable open loop gain and bias
figures. These should be stabilized.
You can imagine it as you like, but you can assume it's fairly simple.
The circuitry is push-pull complementary. If you build such a thing with no
degeneration, you contend with high variable open loop gain and bias
figures. These should be stabilized.
You can imagine it as you like, but you can assume it's fairly simple.
A conceptually simple approach might be 1 Farad cap across a 0.2R degeneration resistor, but that would be impractical. Or would it? AVX SCMR22C155MSBA0 is 1.5F, 5V, ESR=9mOhms and has a relatively small 16mm x 24mm radial package.
Because I still cannot really grab the phase margin problem I want to warn people seeing or even building F4 beasts similar to the circuits I posted that they could be unstable.
On the other side all builds I did showed never any oscillation tendency.
So I relax now a bit......:--))
On the other side all builds I did showed never any oscillation tendency.
So I relax now a bit......:--))
Because I still cannot really grab the phase margin problem I want to warn people seeing or even building F4 beasts similar to the circuits I posted that they could be unstable.
On the other side all builds I did showed never any oscillation tendency.
So I relax now a bit......:--))
Yes, I do not know if low values phase and gain margin are a problem when the OLG is relatively low. Perhaps Nelson's setting of the -3dB frequency well below the frequencies where there might be an oscillation addresses the issue.
An externally hosted image should be here but it was not working when we last tested it.
Perhaps you can educate us poor blokes with either facts or opinions. Perhaps point us at some relevant theory.I have no issues with any of this, but I'm evil so I'm enjoying watching you blokes suffer in your jocks.
Hahaha
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