How does opamp sharing by switching work?

[A.Anand Srinivasan]

i found a ieee paper stating how a opamp is shared by switching.... i found 4 capacitors are being used given in the figure below to sample the input signal... after that one of the capacitors is used in feedback across the opamp and the other 3 capacitors are connected to a supply level based on input form a sub ADC.... i didnt understand how this works... can somebody explain the circuit....

I'm uploading the ieee paper also...

 

[hr_rezaee]

opamp sharing

hi
as I know this image is a simple 2.5 bit gain stage and does not relate to opamp sharing.
you can find it in pipeine theses or books.
regards

 

[A.Anand Srinivasan]

Re: opamp sharing

k... in the ieee paper i have posted it has been said referring to this circuit a logic explaining the usage of the four capacitors and the switching of one cap to the feedback path and connecting the other three to one of the three references (VrefT, Vcom or VrefB) please explain that.....