Time-frequency analysis for multistage A/D converter diagnosis

In this paper, we propose a method based on the time-frequency representation for the diagnosis of a multistage parallel pipelined A/D converters which presents harmonic distortion when all the stage are excited. First, a theoretical background of the joint time-frequency analysis is given and an algorithm using the Fourier transform approach with a Gaussian window is proposed. After a brief presentation of the multistage parallel-pipelined A/D converter architecture, its simulated version with three stages is presented. Due to its architecture, this study emphasizes the fact that faults span non-stationary phenomena. Finally, the time-frequency representation should be more adequate in order to analyze the time arrival of this phenomena. Indeed, this information allows a better diagnosis of this kind of converter.