Thank you,willyboy19
What you mean is that when we design the op-amp used in the integrator,we need not to have a phasemargin larger than 45(or 60),why can we do it in this manner? would the op-amp oscillate in lower frequency than the close loop bandwidth? perhaps the feedback capacitor of the integrator(CF) can help to compensate the op-amp?
I have another question: the close loop gain of an inteegrator is Ci/Cf, so we can say the feedback factor of the negative feedback sysytem(the integrator) is Cf/Ci,which is always bigger than 1,but in a negative feedback sysytem,the feedback factor should be equal to orsmaller than 1,I am confused
Can somebody help me? Thank you in advance.