A Full Current-Mode Timing Circuit with Dark Noise Suppression for the CERN CMS Experiment

In this paper we present an analog circuit for the new MIP Timing Detector of the CMS experiment at CERN, featuring, for the first time, a silicon implementation of the Differential Leading Edge Discriminating technique to suppress SiPM dark noise. This technique also stabilizes the baseline, leading to a time resolution of 25 ps at beginning of life and 55 ps at end of life while dissipating less than 4 mW. The full analog front-end ASIC has 32 channels and has been designed in a CMOS 130 nm technology with a total die area of 8.5 x 5.2 mm2. The radiation tolerance of this design has been confirmed by radiation tests.