mrcupido
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Shown is the test circuit for a switched capacitor circuit. From the plot waveform, the output for a square wave input is a triangle waveform.
However, the closed loop gain is supposed to be 0.5 because of the ratio Cs/Cf, but my output results to have a gain of 250. Could anyone help me fix the closed loop gain?
Op-Amp Specfication:
Folded Cascode w/ Class AB Output Stage and Gain Boosting
DC Gain: 25,000
GBW: 150 MHZ
SR: ~ 40 V/us
I also tried it with a simpler amplifier (Folded Cascode with Gain Boosting w/o Output Stage), DC Gain = 1,300
but it still has a gain instead of attenuation.
The non overlapping clock has a frequency of 20.48 MHZ, and the input signal is 10 KHZ.
P.S. : Vbias4 of the amplifier is for the SC-CMFB.
Thanks for the help.
However, the closed loop gain is supposed to be 0.5 because of the ratio Cs/Cf, but my output results to have a gain of 250. Could anyone help me fix the closed loop gain?
Op-Amp Specfication:
Folded Cascode w/ Class AB Output Stage and Gain Boosting
DC Gain: 25,000
GBW: 150 MHZ
SR: ~ 40 V/us
I also tried it with a simpler amplifier (Folded Cascode with Gain Boosting w/o Output Stage), DC Gain = 1,300
but it still has a gain instead of attenuation.
The non overlapping clock has a frequency of 20.48 MHZ, and the input signal is 10 KHZ.
P.S. : Vbias4 of the amplifier is for the SC-CMFB.
Thanks for the help.