A 19-bit monolithic charge-balancing A/D converter

Abstract

Existing high-resolution ADC topologies are expensive, complicated and vulnerable to switch leakage at high temperature. This thesis introduces the Modified Landsburg ADC, a high-resolution converter optimized for minimum cost and die area. Switch resistance cancellation, charge-injection compensation and auto-zero methods are used to build a simple and robust ADC which will operate reliably across the military temperature range. Implemented on a 0.25[mu]m CMOS process, with a die area of under 300mil², the Modified Landsburg ADC achieves an ENOB of 15.6 bits and an SNR of 95.8dB at 5 Samples/s while consuming <2mW. It enables the integration of a high-resolution converter in smaller, cheaper systems.