vivkr
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Hi Lutz,
First of all, a clipping integrator is a nonlinear system and so I would be a bit careful defining phase in the same way as for linear systems. That being said, a clipping integrator is somehow like a lossy integrator, since the opamp input will no longer be a true virtual ground anymore and so some charge is now being lost and not ending up on the integrating cap. The finite gain of an opamp also causes it to be lossy and keeps the phase at slightly less than 90 degrees. A clamping opamp is like a very low-gain or even a no-gain opamp.
And a lossy integrator has a phase shift less than +90 degrees. On the other hand, if you were to place a clipping element after an ideal integrator, then the original integration was still correct (with a phase shift of 90 degrees).
Does that help answer the question?
Regards,
Vivek
P.S.: There are many things that one may not find in the literature. They may be there but in some obscure corner, or no one may have bothered to think about them.
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