How to implement the coefficients of feedforward in the SDM

[stormeyes]

Hi,everyone
The topology which I used is shown in figure,but the coefficients of feedforward is not integral when the modulator is stable. I am confused about how to implement the coefficients of feedforward in the sigma delta modulator in schematic circuit. If a1=0.03245 Just as show in the fig,how to implement it in circuit? I haven't found any papers or books about that.Who can tell me ? Are there any papers available
Thanks.

 

[sunking]

for SC, use cap. ratio.
for CT, use current/voltage ratio

 

[stormeyes]

I am still confused about how to implement that. Does it need an amp when using cap.ratio? just like the switched-capacitor gain circuit? Is there any paper containing the schematic circuit of it?
Thanks.