A portable and fault-tolerant microprocessor based on the SPARC v8 architecture

The architecture and implementation of the LEON-FT processor is presented. LEON-FT is a fault-tolerant 32 bit processor based on the SPARC V8 instruction set. The processors tolerates transient SEU errors by using techniques such as TMR registers, on-chip EDAC, parity, pipeline restart, and forced cache miss. The first prototypes were manufactured on the Atmel ATC35 0.35 μm CMOS process, and subjected to heavy-ion fault-injection at the Louvain Cyclotron. The heavy-ion tests showed that all of the injected errors (>100,000) were successfully corrected without timing or software impact. The device SEU threshold was measured to be below 6 MeV while ion energy-levels of up to 110 MeV were used for error injection.