Revisit to Accurate ADC Testing with Incoherent Sampling Using Proper Sinusoidal Signal and Sampling Frequencies

Abstract

This paper describes that the mature ADC testing method with a simple test system using the incoherent sampling and the standard algorithm of windowing and FFT with 4Kpoint data can measure the SINAD of our target 12-bit SAR ADC accurately by proper setting of the input and sampling frequencies, which is industry-friendly. We show the input sinusoidal signal and sampling clock frequency relationship for accurate testing of the ADC dynamic characteristics with an incoherent sampling method using a flat-top window. We have clarified the measured SINAD accuracy of the input signal frequency dependency for a fixed sampling frequency, a specified resolution of the ADC under test and a given number of FFT points (data samples) in the incoherent sampling environment. Mature technology combinations with their optimal usage and without advanced methods can lead to the low-cost high-quality testing of the ADC, which can be well accepted in industry. Their analysis, simulation and experimental results are shown.