Characterization of Metrological Grade Analog-to-Digital Converters Using a Programmable Josephson Voltage Standard

A test bench has been developed for systematic characterization of high-resolution analog-to-digital converters. The reference signal is generated by a programable Josephson voltage standard. Three 24-bit digitizers have been characterized. Noise performance has been measured at direct current using the Allan deviation, whereas integral nonlinearity has been measured with quasi-dynamic stepwise triangular waveforms at frequencies between 0.5 Hz and 1 kHz. None of the digitizers outperforms all others for each tested characteristics. Therefore, such a systematic characterization provides the overview needed to identify the most suitable digitizer for a given application.