Performances of typical high energy physics applications in flash-based field-programmable gate array under gamma irradiation

Recent field-programmable gate arrays (FPGAs) based on flash memories offer a high radiation tolerance. We discuss potential applications of the Microsemi IGLOO2 FPGAs in high energy experiments. We implement a 24 channel time-to-digital converter with a time binning of 0.78 ns and evaluate the performance. Differential and integral non-linearity is measured to be far below the time binning. The time resolution obtained is approximately 0.25 ns. The FPGA was exposed to gamma rays with a total ionizing dose of 300 Gy. The function of the configuration memory is monitored and the degradation of the performance on the ring oscillator and high-speed transceiver is measured. The errors during firmware download and verification of downloaded firmware have been observed at 110-120 Gy and 80-90 Gy, respectively. The functionality of the ring oscillator and high-speed transceiver remains up to about 200 Gy.