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Small bump in an opamp uses as integrator

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firsttimedesigning

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So I have designed an Op-Amp that has a gain of 80dB and its phase margin is about 45 degrees so it is stable. the problem is that when i hooked it up with a capacitor and resistor to make it operate as an integrator, it always has this small bump at the beginning. When the input voltage is changed at 500ns it also has another bump (please see attached file). I know this bump has to do with the capacitor that is connected at the output. is there anyway to eliminate this bump?
any suggestion is welcome. thank you
 

arsenal

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integrator

How did u get the bumping? or is it the overshoot?
Try increase the pm to about kinda 60?
 

robicyang

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Re: integrator

i think the phase margin is too small, 45 withou the load cap. because of the effect of the load, the load phase will affect the phase margin.
 

firsttimedesigning

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Re: integrator

thank you for the reply.
i did try to increase the pm by increasing the loading capacitance.
however, the bump just gets even bigger....
 

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