A Versatile Mixed-Signal Large Dynamic Range Front-End ASIC for High Capacitance Detectors

A 64-channel mixed-mode ASIC, suitable for particle detectors of large dynamic range and high capacitance up to 100 pF, is presented. Each channel features an analogue front-end for signal amplification and filtering, and a mixed signal back-end to digitize and store the signal information. The analogue part consists of a versatile low impedance pre-amplifier based on Regulated Common-Gate amplifier, and two shapers optimised for time and energy measurements. The back-end part mainly includes discriminators, TDCs and ADCs, which are used to process the signal and encode both the time of arrival and the charge of the input signal with a fully digital output. The programmable gain of the front-end (2-400 fC input dynamic range) and the versatile back-end allow the readout of different types of gaseous detectors.The ASIC is designed for an event rate up to 100 kHz per channel with a power consumption less than 10 mW/channel, has been fabricated in a 110 nm CMOS technology. This chip is a revised version of the TIGER ASIC, which was developed for the readout of the new BESIII CGEM Inner Tracker.