New clock feedthrough cancellation technique for analogue MOS switched-capacitor circuits

Abstract

A new technique for minimising DC offsets caused by clock feedthrough in switched-capacitor circuits is presented. Unlike some techniques presented in the past, the clock feedthrough cancellation is dependent only on matching and the common mode rejection ratio of the op-amps. The technique is quite general and can be applied to most switched-capacitor circuits that use differential input op-amps.