Dark Matter Particle Explorer (DAMPE) is a Chinese scientific satellite designed for cosmic ray study with a primary scientific goal of indirect search of dark matter particles. As a crucial sub-detector, BGO calorimeter measures the energy spectrum of cosmic rays in the energy range from 5 GeV to 10 TeV. In order to implement high-density front-end electronics (FEE) with the ability to measure 1848 signals from 616 photomultiplier tubes on the strictly constrained satellite platform, two kinds of 32-channel front-end ASICs, VA160 and VATA160, are customized. However, a space mission period of more than 3 years makes single event effect (SEE) a probable threat to reliability. In order to evaluate the SEE sensitivity of the chips and verify the effectiveness of mitigation methods, a series of laser-induced and heavy ion-induced SEE tests were performed. Benefiting from the single event latch-up (SEL) protection circuit for power supply, the triple module redundancy (TMR) technology for the configuration registers and optimized sequential design for data acquisition process, VA160 and VATA160 with the quantity of 54 and 32 respectively have been applied in the flight model of BGO calorimeter with radiation hardness assurance.
تحميل البحث