Extreme Total Ionizing Dose Survival of a COTS Artix-7 FPGA Under Prolonged Gamma Irradiation

Commercial Off-The-Shelf (COTS) FPGAs offer a low-cost platform for nuclear robotics, yet their radiation survivability is often underestimated because vulnerable onboard peripherals fail before the FPGA silicon. Furthermore, most studies irradiate unpowered devices at high dose rates, leaving Enhanced Low Dose Rate Sensitivity (ELDRS) behavior largely unexplored for these architectures. This paper presents an extended gamma irradiation campaign at Harwell, UK, where a Trenz Electronic TE0725 board hosting an AMD Artix-7 FPGA was continuously powered and actively benchmarked via 14m of remote cables for 93.6hours, accumulating a Total Ionizing Dose (TID) of 6,680Gy ±10%. Post-irradiation diagnostics confirmed that the Artix-7 silicon fabric remained functional and reprogrammable via JTAG, with stable internal voltage and temperature readings; only the QSPI flash memory failed, preventing autonomous reconfiguration. This work represents one of the longest continuously powered COTS FPGA irradiation campaigns in the literature, demonstrating survival beyond the ≈6.7 kGy threshold without local shielding, differentiating this work from previous lead-shielded architectures. The findings validate remote power delivery as a practical, cost-effective strategy for deploying COTS FPGAs in high-radiation environments.