Bob Pease and opamp-modelling

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I can't make out what he means from the rendering of the article - makes no sense to me either.

There is a simple way around his dislike of using the -3dB point of the Laplacian open-loop gain expression:

H=3D Ao ----------------- 1 + (s*Ao/wo)

where Ao is the dc open loop gain, and the new wo is the radian frequency at which the gain goes to unity. While it is a tiny bit ugly (Ao appearing twice), it can now be varied without altering wo.

-f

As usual, Pease tries to make things too complicated.

The "AC" gain is simply GBW/s, where s is the Laplace variable.

DC gain is just a straight _horizontal_ line, of value, Gdc.

The "corner" is the intersection of Gdc and GBW/s.

See the behavioral OpAmp model on my website for more details.

...Jim Thompson

Thanks for answering but I think the expression you suggested should be: A0 H=3D----------------- 1+ s /w0

with A0 the DC-gain and w0 the openloop corner frequency (rad/ s) of course Bob's equation (4) still remains a mystery

maybe he does, but to be sure of that we first have to know what he really meant with the fourth equation... I guess we all know here the first order opamp model but Bob seems to want to replace it with a more accurate model, I really like to know what it is, I don't care if it is in the time domain or in the f-domain as converting from one to the other is not difficult.