Need help to figure out the function of this diode connected capacitor (is it what it is called?).
Comparing the 2 cct attached, the only diff. is the diode connected at the capacitor. The capacitor basically acts as phase compensation from input stage to the output stage, but by adding the diode in between the cap, what is the effect of the diode to the whole cct?
This seems to be an op amp made from an old bipolar technology. And, this diagram seems to be an equivalent diagram. My hunch is that they are indicating this capacitor to be a depletion capacitor as a poly-poly cap cannot be realized in this process.
Did you confirm if there was indeed a diode in the layout in parallel with the cap? Or, is this just a cap realized using the depletion region of a pn diode(base-emitter or a collector-base diode?)