FPGA-DSP Tightly Coupled PHM Architecture with Radiation-Tolerant Mechanisms for Spaceborne NOR Flash

The growing demand for low-cost, high-reliability onboard storage in commercial aerospace missions poses significant challenges for industrial-grade NOR Flash memory, which must contend with gradual total-ionizing-dose (TID) degradation and potentially abrupt single-event effects (SEEs) in space radiation environments. This paper proposes an FPGA–DSP tightly coupled Prognostics and Health Management (PHM) architecture for spaceborne NOR Flash. The architecture is implemented with a TMS320F28335 floating-point DSP and an A3PE3000 Flash FPGA, establishing a complete “sensing–evaluation–decision–execution” closed loop. The time-domain evaluator uses sliding-window least squares for online remaining useful life (RUL) prediction, while the spatial-domain evaluator performs dynamic wear leveling through minimum-error replacement. A Dual-Domain Collaborative Arbiter (DDCA) fuses both assessments to schedule adaptive refresh, dual-mode Reed–Solomon (RS) coding, backup pre-switching, and eFuse isolation. The experimental claims in this study are limited to laboratory 60Co γ-ray TID irradiation at 1 rad(Si)/s; the SEE-oriented functions are architecture-level mitigation provisions and have not yet been validated by heavy-ion, proton, or neutron beam tests. Using four control groups, the proposed scheme reached an observed failure total dose of 24.7 krad, compared with 12.3 krad for the unprotected baseline. Under the tested control group definitions, this corresponds to a 100.8% improvement and a 4.9 krad excess over the additive estimate from the two single-domain groups. Because independent device-level repeats were not available, these dose values are reported as observations rather than population means. The complete PHM decision loop executes in under 60 μs.