Hi every one :
I found in a op-amp there is a capicitor in the first stage connected
between the VDD and one of the differential output . I think this capicitor
is for compensation purpose . But I don't know how to calculate the
pole of this capicitor and how this capictor effect the other polse/zeros
of this op-amp .
Is there someone can help me ?
that cap is the decoupling capicator it is not the compensation capicator .
dont know exact role of the cap but i will let u know soon
Hi :
But the capicitor really introduce a pole and maybe it change the location
of the other poles . In fact at high frequency , this capicitor decrease
the gain of the first stage to one-halt of the dc value .
ya you are saying right but the as i think the cap is connected to the gate
through vdd and the gate will be connected to the source or drain of the other transistor
so it will not effect the gain or bandwidth.
But the capicitor really introduce a pole and maybe it change the location
of the other poles . In fact at high frequency , this capicitor decrease
the gain of the first stage to one-halt of the dc value .