Configuration Self-Repair in Xilinx FPGAs

The usage of static random access memory-based field programmable gate arrays (FPGAs) on high-energy physics detectors is mostly limited by the sensitivity of devices to radiation-induced upsets in their configuration. In this paper, we describe a scrubber core designed for Xilinx FPGAs, based on configuration redundancy. When no upsets happen in homologous redundant bits and the scrubber is functional, the adopted redundancy makes it possible to correct all the errors. In fact, the scrubber corrects its own configuration and the one pertaining to a given user design. We discuss the architecture and two implementations of the scrubber, corresponding to different flavors of triple modular redundancy. We report results from proton irradiation tests, which prove that our core can extend the lifetime of a benchmark circuit up to 290%