Digital calibration of inter-stage nonlinear errors in pipelined SAR ADC

Abstract

A digital calibration technique to linearize the residue amplifier in pipelined SAR ADC based on Independent Component Analysis (ICA) is presented. The proposed technique utilizes a single, one-bit pseudorandom noise (PN) to simultaneously identify all coefficients of a correction polynomial. Behavioral simulation results demonstrate the effectiveness of the technique, in which the SNDR and SFDR performance of a 12-bit pipelined SAR ADC is improved from 54 dB and 69 dB to 72 dB and 100 dB, respectively. Some circuit design details are included for the PN injection circuit as well as the digital calibration logic.