HardCAM: A 65 nm radhard CAM design and evaluation for space applications

This paper presents the design and first experimental validation under heavy ion (HI) irradiation of a Content Addressable Memory (HardCAM) fabricated in 65 nm CMOS technology. HardCAM was experimentally tested alongside a standard SRAM array to assess data integrity and proper function under HI beam irradiation. While the SRAM exhibited increasing error rates and consequent data corruption due to single event effects, radhard HardCAM maintained correct operation even under extreme conditions that induced several bit flips per memory row. HardCAM requires no error correction mechanism. It applies similarity, or Hamming distance tolerant search, to endure and tolerate errors rather than correct them. Our experimental results establish HardCAM as a viable and robust CAM solution for radiation-sensitive applications, such as space and aerospace systems.