Event rates were calculated for LEO (ISS) and GEO environments by combining CREME96 orbital integral flux estimations and simplified SEE cross-sections according to methods described in Heavy Ion Orbital Environment Single-Event Effects Estimations. A minimum shielding configuration of 100mils (2.54mm) of aluminum and worst-week solar activity is assumed. (This is similar to a 99% upper bound for the environment). Table 5-2 lists the event rate calculations using the 95% upper-bounds for the SEL. It is important to note that this number is for reference since no SEL events were observed.

MTBE is the mean-time-between-events in years at the given event rates. These rates clearly demonstrate the SEE robustness of the THVD9491-SEP in two harshly conservative space environments. Customers using the THVD9491-SEP must only use the above estimations as a rough guide and TI recommends performing event rate calculations based on specific mission orbital and shielding parameters to determine if the product satisfies the reliability requirements for the specific mission.