Linearity testing issues of analog to digital converters

Abstract

This paper is a detailed overview of the practical issues related to linearity testing of analog to digital converters. The focus is on the available technology and methods for ADC linearity testing, and the goal is to demonstrate the issues and problems affecting the test capability. Delta-Sigma DACs and LC filtered RF Frequency synthesizers are covered as linear sources for the ADCs. Histogram based ramp and sine wave methods are covered as linearity test techniques. Integral non-linearity (INL) plots from a 10-bit 20MSPS pipeline ADC are given to demonstrate the test problems and performance. This work attempts to close the gap between the general theory and actual implementation problems of linearity tests for high performance ADCs.