Development of a high-granularity, high-precision timing readout electronics system for large-area MRPC detectors
Multi-gap Resistive Plate Chamber (MRPC) detectors offer excellent time resolution and detection efficiency, creating a strong demand for high-precision, highly scalable timing readout systems. In this work, a readout electronics system is designed for a large-area 100*100 cm MRPC detector containing 2400 high-granularity 2*2 cm pad channels. The system consists of two Front-End Boards (FEBs), a central clock distribution module, and a back-end DAQ aggregator. Each FEB is equipped with 40 32-channel PETIROC2B ASICs mounted directly behind the sensing pads. An automated S-curve calibration procedure equalizes the baseline dispersion across all 2400 channels, reducing the FWHM of the baseline voltage distribution from 50 mV to 12 mV and establishing a uniform triggering threshold. Signal-injection measurements confirm an intrinsic single-channel electronic time resolution of 33 ps RMS, alongside inter-chip and inter-board time resolutions of 43 ps RMS and 45 ps RMS, respectively. This high-granularity, high-precision timing readout system can be widely applied to Time-of-Flight systems, cosmic-ray muon imaging, as well as other fast-timing detector systems.