[Don Pearce[_3_]]

On Tue, 13 Sep 2011 12:08:14 -0500, John Byrns
wrote:

So if I follow you, you are not talking about a single overall negative
feedback
loop containing a dominant pole within, but instead you are talking about
nested
feedback loops where the dominant pole within the overall feedback loop is
created by a second shorter internal feedback loop that rolls off the high
frequencies?

That is exactly what a dominant pole is - a nested feedback system in
which the voltage amplifier is controlled by a single capacitive
feedback element. The overall feedback which surrounds it is flat, and
composed of two resistors, the ratio of which sets the gain of the
amplifier.

I beg to differ, a "dominant pole" does not require nested feedback loops, it
can also be a simple pole within a single overall feedback loop controlled by
the same two resistors you describe.

Oh jeez. OK. But the way it is done 99%, no, 100% of the time is by
putting the pole around the voltage amplifier. That way the dominant
pole reduces the voltage amplifier distortion at high frequencies. If
you just stick in a pole it can't. Why would anyone compromise their
HF open loop gain for nothing?

d