Error-locality-aware linear coding to correct multi-bit upsets in SRAMs

Abstract

High-energy cosmic radiation is the major source of soft errors in SRAMs that can cause multi-bit upset around the location of the strike. In this paper, we generalize the coding problem for error detection and correction of both local (burst) and global (random) errors. We suggest using error-locality-aware codes for SRAM memories to correct single-bit or multi-bit upsets as well as physical defects. Solving the coding problem with a SAT-solver, we have found codes to correct double global or multiple (>=3) local errors for 8, 12, 16, and 24-bit memories. For 16-bit memories, we propose a code that corrects two global or four local errors. With the same cost, our proposed code provides extra reliability than double-error-correcting BCH code. For 12-bit memories, we suggest a code that corrects two global or five local errors and has the same cost as triple-error-correcting Golay code but provides better reliability against multi-bit upsets. For memories of other widths, using syndrome analysis, we demonstrate the possibility of designing codes to correct any arbitrary number of local and global errors.