A Calibration-Free Pipelined-SAR ADC With Cross-Stage Gain-Mismatch Error Shaping and Inherent

Abstract

This article presents a calibration-free pipelined- successive-approximation-register (SAR) analog-to-digital converter (ADC) based on the proposed cross-stage gain- mismatch-error shaping (CS-GMES) mechanism. The CS-GMES is realized by including the entire 2nd stage into MES operation to unify the gain error and the 2nd-stage mismatch error. A feedback capacitor provides cross-stage connection and mismatch reference, and prevents saturation issues. Besides, low-cost noise shaping (NS) is achiev