A highly energy-efficient, highly area-efficient capacitance multiplexing switching scheme for SAR ADC

摘要

The capacitance multiplexing technology is put forward innovatively in this letter. The technology divides the traditional differential capacitance array into two parts: high bits array and low bits array. And through a simple control circuit, this method realizes low bits capacitance array multiplexing. It can improve the performance of successive approximation register (SAR) analog-to-digital converters (ADC). Based on the capacitance multiplexing technique and split-MSB mode, a highly energy-efficient and highly area-efficient capacitance multiplexing switching scheme for SAR ADC is proposed. The novel switching scheme can achieve a 86% reduction in capacitor area and 99.37% switching energy reduction compared with the conventional switching scheme for SAR ADC, respectively.