Gain error, offset error and ENOB estimation of an A/D converter using histogram technique

Abstract

This paper reports estimation of gain error, offset error and Effective Number of Bits (ENOB) of an Analog to Digital Converter (ADC) using histogram technique for sine wave as input test signal. Computation of code transition levels of ADC transfer characteristics is done by collecting large number of samples of full scale sine wave and estimating cumulative histogram. Gain error and offset error are determined from first and last code transition levels of ADC transfer characteristics. ENOB is determined from actual rms error and ideal rms error. Simulation of 5–8 bit ADC transfer characteristics is done and ADC parameters are estimated by introducing arbitrary nonlinearity errors. Comparison of simulation results of this method with existing methods is done and improvement in results is obtained as compared to existing. The main aim of dynamic testing is to determine functional parameters of an ADC which are responsible for the accuracy, resolution, speed and linearity of the conversion process.