Thanks for the reply. I am looking into designing a pipelined ADC with switched capacitors.Lets say I have 4 stages in my ADC. Would this mean that I would have to have a bare minimum of 4 opamps as a starting point? Also I see that for pipelines ADC they pass the input signal through an aliasing filter, perform sample and hold, pass it through a comparator and at the same time through a DAC followed by a gain stage(subtract the value at each stage). When I am trying to simulate these block I would have to build each of these in terms of CMOS transistors. There are many good resources for opamp design. There are also good resources for a comparator(I can use a very high gain open loop opamp itself for the time being. I would not have to build anything else.) What I am having a problem with is the design of the MDAC unit. I know there are a couple of tutorials online about switched capacitors. But none of them are complete enough to help me get started with building an MDAC. What would you suggest is a good reference for me to get started with designing an ADC?