superleaf
Junior Member level 3

Hi,
I have designed a two-stage opamp,and then i use the opamp to construct a low-pass filter,through the AC simulation,i found that the amptitude drop at about -150dB instead of 0dB at the low-frequency region,this result is unbelievable,and i don't know why?the gain of the opamp is about 6300,the bandwidth is about 60kHZ~~~
I have designed a two-stage opamp,and then i use the opamp to construct a low-pass filter,through the AC simulation,i found that the amptitude drop at about -150dB instead of 0dB at the low-frequency region,this result is unbelievable,and i don't know why?the gain of the opamp is about 6300,the bandwidth is about 60kHZ~~~