A Class of Odd-Weight-Column SEC-DED-SbED Codes for Memory System Applications

Error correcting codes are widely used in memory systems to increase reliability. Especially in a memory systern that uses byte-organized memory chips, which each contain b (≫1) output bits, a single chip failure is likely to affect many bits within a byte. Single-bit error correcting-double bit error detecting-single b-bit byte error detecting codes (SEC-DED-SbED codes) are suitable for increasing the reliability of memory system. This correspondence presents a new class of odd-weight-column SEC-DED-SbED codes for b = 4. The code length is 2^r-1 - 2^[r/2], where r is the number of check bits and [ ] denotes the ceiling or next largest integer. The proposed SEC-DED-S4ED codes are the best-known codes.