how to decide gbw of ota
Thank you Vamsi!
As we known, when apply a large signal to the opamp, for example 1Vpp, one of the input transistor of opamp turns off, the other is still on, so the slew rate SR=Iss/Cc.
But for an amplifier, we also want to get a voltage gain (Vout/Vin). For exampe gain=10, that means for a 2Vpp output, the input signal is only 0.2Vpp. this situation is different with gain=1, the slew rate at this situation should be higher in order to meet the request.
Now the compensation capacitance I used is 500ff, the tail current is 200us. but the SR(400V/us) seems still not enough to work at 10MHz sampling frequency(T=100ns). How should I do? It seems a little difficult to go on increasing the tail current.