Method and apparatus for preventing inherent error propagation of successive approximation register analog-to-digital converter through digital correction

Abstract

A method and apparatus for preventing inherent error propagation of a successive approximation register (SAR)-based analog-to-digital converter (ADC) through digital correction. A sample-and-hold circuit captures an input analog signal and generates a hold sample of the input analog signal. A digital-to-analog converter (DAC) generates an iterative sample corresponding to a digital code for each iteration. A comparator compares the hold sample and the iterative sample and generates a decision signal based on the comparison. A successive approximation register updates the digital code for each iteration based on the decision signal and supplies the updated digital code to the DAC. The SAR ADC includes an error detection circuit to detect an error condition. A controller ceases iteration operation if the error condition is detected and outputs the current digital code as a result.