Pulsed-Laser Testing to Evaluate Transient Dose Rate Effect on a Commercial-Off-the-Shelf FPGA

To overcome the complexity and challenges of transient γ irradiation experiments, this paper adopted pulsed lasers to simulate the transient dose rate effect (TDRE) on a commercial off-the-shelf (COTS) field-programmable gate array (FPGA), taking advantage of good stability, low interference, high efficiency, and low cost. Three test programs were designed for the Virtex-5 XC5VSX95T FPGA, including one program used in previous transient γ irradiation experiments. Laser experiments involved a wide energy range, and recorded failure features of the device under test (DUT) and photocurrents on the power supplies. By comparing the results with transient γ irradiation experiments, it was demonstrated that pulsed lasers can be used to effectively simulate FPGA’s TDRE, showing consistent effect characteristics. Additionally, the sensitivity of the internal clock and logic resources of the FPGA was analyzed, finding that delaylocked loops (DLLs) have a high sensitivity and that disturbances in the logic resources could propagate. There are multiple factors affecting the internal sensitivities. Furthermore, like transient γ rays, high-intensity pulsed lasers would also induce dynamic reconfiguration of the FPGA, which was analyzed specifically. These research findings are important supplements to studying FPGA’s TDRE, and also demonstrate a significant prospect of using pulsed lasers to simulate the TDRE in very large-scale integrated (VLSI) circuits.