On-Orbit Single Event Effect of the Digital Signal Processor of the Alpha Magnetic Spectrometer and Discrepancy Analysis for the Rate Prediction

Three hundred commercial off-the-shelf ADSP-2187L chips on AMS-02 have been operating without major problems on the International Space Station since launch. The conversion rates from the single event upset (SEU) to single event function interrupt varied with the operation methods. The correlation between the on-orbit SEU and radiation environments during the 24th solar cycle was studied. The on-orbit SEU rate was much lower than expected. Possible reasons for the higher predicted SEU rate were discussed and thought to be the different circuit operations of the ground test method and the on-orbit one in the sensitive linear energy transfer range.