SEE Enhancement of Advanced Commercial Microprocessors for Space Applications

Commercial microprocessors are challenged for use in satellite computers due to the damaging effects of radiation, particularly single event upsets (SEU) and functional interrupts (SEFI). Space Micro has developed innovations for mitigating SEU/SEFI, enabling the use of high-speed microprocessors (>1,500 MIPS) with improved SEU tolerances (>1E-5 errors/day). Time-Triple Modular Redundancy (TTMR) applies traditional triple modular redundancy on a single microprocessor. TTMR improves SEU rates substantially. SEFI is solved through the use of a SEFI ?Hardened Core? circuit, external to the microprocessor, along with SEFI recovery software embedded into application code. It monitors the ?health? of the processor, and if SEFI occurs, forces the processor to return through a series of escalating events (interrupts, reset). Space Micro successfully demonstrated monitoring and recovery of Pentiums from SEFI, 100% of the time, using a prototype of the H-Core in a proton environment. This is significant in being the industry?s first (only) demonstrated solution for SEFI in microprocessors. In Phase II, the H-Core will be advanced into a radiation hardened IC that operates with any advanced microprocessor, allowing automatic return to operational status after a SEFI event. Additionally, software recovery algorithms will allow applications to recover part or all of their lost data.