Active charge pumping power-saving technique for SC integrators

Abstract

This paper presents a method to save the power consumption of switched capacitor (SC) integrators in sigma-delta analog-to-digital converters (ADCs). It is based on open-loop charge injection in the output of the first integrator. The injected charge is a continuous function of the input voltage and feedback, the idea is to minimize the initial transient voltage in the input of the first amplifier and hence bypass the slewing of the amplifier. Circuit simulations show that a 10-bit performance can be obtained by about 60% power dissipation, compared to a traditional implementation.