65 nm CMOS 8 mV/fC, 14.6 ns Rising Time Analog Front-End for ATLAS Muon Drift Tubes Detectors

This paper presents an ultra-low power, area-efficient 4-channel front-end electronics for Monitored Drift Tubes (MDT) at Atlas Experiment. The proposed design is composed by low-noise Charge Sensitive Preamplffier (for charge-to-voltage conversion), a continuous-time Shaper/filter for Bipolar Time-Domain Pulses feeding a dynamic (no-clocked) Comparator (for voltage to time conversion). The system is designed to detect an input charge in the range of 5-100fC. The peaking time of Analog channel is 14.6 ns and exhibits a sensitivity of 8 mV/fC. The design has a single mode of operation, time-over-threshold (ToT). At the output the ToT encoding of input charge is provided in low-voltage differential signal, for connecting with TDC board, along with digital CMOS level signal. The design is operated from a single 1.2 V supply voltage. The chip is realized in 65 nm CMOS technology and has a total area occupancy of 4 mm2.