Measurement of Parameters of Analog-to-Digital Converters Based on the NI Hardware-Software Complex in the Course of a Radiation Experiment

The paper presents an automated system for functional and parametric control of analog-to-digital converters (ADC) during a radiation experiment. The automated measuring system is based on the combined use of modular PXI equipment manufactured by National Instruments and the signal generator SMA100B manufactured by Rohde & Schwarz (R&S). The PXI-4461 module is the most significant module in the system. Hardware and software operations of the measuring system are discussed in the paper. The parameters controlled during total ionizing dose (TID) tests are listed in the paper alongside the algorithm for parametric control. We describe a histogram method for removing input noise. In order to mitigate drawbacks of histogram method, we measured sample median for each ADC code value during the experiment. With the help of this system, the main static and dynamic parameters of test ADCs are calculated and their degradation during irradiation at the Cs-137 isotope source is shown. Specifications for quantifying ADC dynamic performance were based on an FFT results analysis. Typical TID effects in ADCs are observed: degradation of the transfer function and associated deterioration of the accuracy parameters: integral nonlinearity, differential nonlinearity, offset and gain errors.