Biasing potentials monitoring circuit for multichannel radiation imaging ASIC in-system diagnostics

This paper shows the architecture and simulation results of the biasing potentials monitoring circuit which will be implemented in the next revision of the STS/MUCH-XYTER2 full-size prototype radiation imaging ASIC for the Silicon Tracking System and Muon Chamber detectors which will be built for the Compressed Baryonic Matter experiment at FAIR center, Darmstadt, Germany. The aim of the circuit is to enable remote measurement of important voltages inside the circuit during the experiment lifetime (10 years) and if necessary correct the circuit's settings to restore the optimum performance in the harsh, irradiated environment and power supply fluctuation conditions. The circuit is built with analog multiplexed inputs attached to 8-bit resolution threshold voltage generation digital-to-analog converter with comparator enabling slow, successive-approximation measurements confined within an area of 660 × 208 μm².