A SKIROC2-based prototype electronics system for silicon PIN array

Abstract

Silicon PIN (Si-PIN) diode has been widely used in high-energy physics experiments. The next-generation experiments ask for a large amount of the Si-PIN diode arrays, leading to a requirement for the electronics system with features of higher integration and lower power consumption than the traditional ones. The aim was to design and implement a prototype of multi-channel electronic system, which is based on the SKIROC2 ASIC. The system is also considered as the pre-research of the silicon–tungsten (Si-W) ECAL for CEPC. The prototype is divided into two parts, so that it has the potentiality for the expansion of more readout channels. The front-end board (FEB), which carries a Si-PIN diode array and an ASIC of SKIROC2 on it, provides high voltage to the Si-PIN diodes and processes the signals as well. The FEB is configured by a data interface board (DIF) and sends data to the DIF, which then transfers data to PC via USB interface after packing process. The prototype electronics system has been implemented. The equivalent noise level of all the 64 channels is below 0.4 fC. The dynamic range is up to +3000 fC with an integral nonlinearity (INL) of 0.2 %, and the gain non-uniformity is better than 5 %. The energy resolution with 59 keV X-rays from 241Am is about 13.3 % (in RMS), while the signal-to-noise ratio (SNR) reaches about 10.9 for minimum ionizing particles (MIPs). In this paper, a SKIROC2-based prototype electronics system for Si-PIN array, as well as the performance test, has been presented. The system has features of high integration, low noise, and high dynamic range. The SKIROC2, as well as the design concept of the electronics system, can be applied to the preliminary prototype Si-W ECAL of CEPC.