A 32-Channel Cryo-CMOS ASIC for SNSPD Biasing and Readout with Picosecond Timing

Superconducting nanowire single-photon detectors (SNSPD) are a promising technology for particle detection.Although SNSPDs have demonstrated picosecond timing accuracy, scaling up large arrays has proved challenging.In this work, we introduce a 32-channel cryo-CMOS application-specific integrated circuit (ASIC) that can be tightly integrated with SNSPD arrays.The ASIC is designed to operate at a temperature of 4K and can perform up to 32 simultaneous timing measurements with a root-mean-square (RMS) accuracy of 8.0ps.The ASIC includes on-chip circuitry for externally biasing superconducting devices, low-noise amplifiers for reading superconducting devices, high-resolution time-to-digital converters (TDC) for time-tagging events, and serializers for transmitting data to room-temperature electronics.The ASIC is manufactured in a 22nm FDSOI process and occupies an area of 4.0mm x 1.0mm.The performance of the ASIC was verified using custom cryogenic device models internally developed for the 22nm SOI process.Measurement results will be presented at the conference.