HARDWARE COMPLEXITY REDUCED ECC WITH FSD IN MLC NAND FLASH MEMORIES
Generally, Memory cells have been protected from soft errors. Particularly in the case of Flash memories, Due to the increase in soft error rate, the encoder and decoder circuitry around the memory blocks have become susceptible to soft errors as well and must also be protected. In order to control soft errors in the memories, Error control coding (ECC) is used. ECC algorithm correction strength (number of bit errors that can be corrected) depends on the ECC algorithm used to correct the soft errors. Simple Hamming codes can only correct single bit errors. Reed-Solomon code can correct more errors but limited to multiple bit errors only. Hence in order to enhance error correction capability and reduced hardware overhead, we are proposing a new design approach based on product code ECC scheme which consists of fault secure encoder and decoder circuitry for memory designs. We are also using Euclidean Geometry Low-Density Parity-Check (EG-LDPC) codes in Fault secure detector (FSD) which can makes design of FSD simple and can also achieve higher reliability and lower area overhead.
Sribarki Srinath, Bantupalli Divakar