US Patent 7639073 Switched-capacitor amplifier with improved reset phase

A switch-capacitor (“SC”) amplifier includes a two-stage operational amplifier (“OP-AMP”), an input SC network, and a feedback SC network. The two-stage OP-AMP includes a first OP-AMP stage having an output coupled to an input of a second OP-AMP stage. The input SC network is coupled to an input of the first OP-AMP stage. The feedback SC network is configured to selectively couple the output of the first OP-AMP stage to the input of the first OP-AMP stage during a first phase of operation of the SC amplifier and to couple an output of the second OP-AMP stage to the input of the first OP-AMP stage during a second phase of operation of the SC amplifier.