Fred Bartoli wrote:

Eeyore a écrit :
Winfield Hill wrote:

It's nice to see the diff-pair currents going directly to
the output opamp, with it's 6.8k resistors. But why'd ya
steal away loop gain so aggressively by choosing 680-ohms?

It doesn't. The + and - op-amp input nodes see almost no differential ac signal
voltage due to feedback action.

Hence no-need for active loading either. The 680Rs simply set the DC condition.

Win wasn't speaking about this. Well, you've splendidly succeeded in
reducing the loop gain by a 1:11 factor.

Come on then. Let's see your explanation.

Graham