Fault Tolerance Method for Memory Based on Inner Product Similarity and Experimental Study on Heavy Ion Irradiation

Abstract

As the feature sizes of integrated circuits are reduced to the nanometer scale, the total soft error rate (SER) in memory and the proportion of multiple bit upsets (MBUs) are significantly increasing. In order to ensure the information reliability, many error correction codes with strong error correction ability were proposed, such as Reed–Somolon (RS) code and Bose–Chaudhuri–Hocquenghem (BCH) code. However, these error correction codes have limited error correction capability, high algorithm complexity and large data redundancy. In this paper, a novel fault tolerance method for locating and correcting multiple bit errors in memory is proposed based on data similarity. The proposed method uses the inner product as the metric to analyze the similarity of the pre-protected data from the vertical and horizontal dimensions, respectively, and to construct the model of error location and correction. This method performs encoding and decoding in units of blocks and detecting and correcting in units of words, so it can correct any number of bits in a corrupted word with low redundancy overhead. Finally, irradiation tests were conducted on a commercial SRAM, and the feasibility of the proposed method is verified by using heavy ion [Formula: see text]Kr[Formula: see text] as irradiation source.