A stimulus identification method for high-resolution ADC linearity testing using low-precision ramp signals

Abstract

Linearity testing of an analog-to-digital converter (ADC) with automatic test equipment is expensive and challenging. In this paper, an improved method is proposed for high-precision ADC linearity testing to substantially relax the stimulus linearity requirement and reduce the test time. Two nonlinear but functionally related input signals are used as the ADC excitation, and a stimulus error removal technique is used to obtain the test results. This method makes it possible to test the static parameters of high-resolution ADCs by using low-precision ramp signals with fewer sampled points. Compared to the histogram method, the proposed method can save 90% of the test time to achieve the same accuracy. Simulation and measurement results demonstrate the functionality and robustness of the proposed method.