Proton SEU test of MC68020, MC68882, TMS320C25 on the ARIANE5 launcher On Board Computer (OBC) and Inertial Reference System (SRI)

The ARIANE5 On Board Computer (OBC) and Inertial Reference System (SRI) are based on Motorola MC68020 processor and MC68882 coprocessor. The SRI data acquisition board also uses the DSP TMS320C25 from Texas Instruments. These devices were characterized to proton induced SEUs. But representativeness of SEU test results on processors was questioned during ARIANE5 studies. Proton test of these devices was also performed on the actual equipments with flight (or representative) software. The results show that the On Board Computer and the Inertial Reference System can satisfy the requirements of the ARIANE5 missions.