I suspect we will be waiting a very long time before the good professor shows up. I would love to be wrong with that assessment.

Hi Joe,

Yeah that could be true. Either he was thinking in terms of gain blocks or he is very familiar with ways to increase gain. My gut feeling now though is that he made a mistake and that is because of the "two" op amps instead of just one. We all know that two can be used if they have the proper GBWP, but using speed up methods means we dont need two, just one. The need for two spells out the bridge arrangement which would have come about from an error in the details of the op amp.

Kudos to the first one to mention the two bridged amps though

 

The LTSpice idealized opamp is:

.subckt opamp 1 2 3
G1 0 3 2 1 {Aol}
R3 3 0 1.
C3 3 0 {Aol/GBW/6.28318530717959}
.ends opamp

The two parameters I used in my sims were Aol=1e5 and GBW=1e6

Actually I take back my comments above - my equations are fine for this model. I looked at this model and saw the 1ohm output impedance, but it is in parallel with a 15.9mF (millifarad) capacitor (Aol = 1e5, GBW = 1e6), so the output impedance at 1MHz is about 1e-5 ohms, and falling for higher frequencies. This is as good as a voltage source for the circuits considered.