Characterization and testing of analog-to-digital converters (ADCs) are important in many different aspects. Histogram test is a common method to characterize the linearity features of an ADC. Two commonly used stimuli signals are sine waves and Gaussian noise. This paper presents a metrological comparison between Gaussian and sine wave histogram tests for wideband applications; that is we evaluate the performance in characterization of the ADC and the usability of post-correction. A post-correction procedure involves characterization of the ADC non-linearity and then use of this information by processing the ADC output samples to remove the distortion.
The results show that the Gaussian histogram test gives reasonable accuracy to measure non-linearities. However, it does not result in a suitable model for post-correction in wideband applications. A single-tone sine wave histogram will be a better basis for post-correction. Best result can be obtained if the look-up table is trained with several single-tone sine waves in the frequency band.