Optimal Voltage Signal Sensing of NAND Flash Memmory for LDPC Code

Low-density parity-check (LDPC) code can provide stronger error correcting performance in NAND flash memory. LDPC decoder requires accurate soft-decision log-likelihood ratio (LLR) information which demands fine-grained flash memory threshold voltage sensing operations. The threshold voltage sensing operations incur energy consumption and access latency penalty. Therefore, it is important to minimize the flash memory sensing operations without noticeable error correcting performance decreasing. We propose a new flash memory sensing strategy Ununiform-SOR (ununiform sensing in overlapping region) which can reduce 20% flash memory sensing operations than traditional non-uniform threshold voltage sensing without reducing the error correcting performance of LDPC code in NAND flash memory noise channel. The new Ununiform-SOR sensing strategy can reduce more than 20% reading energy consumption than the non-uniform sensing strategy. The abstract goes here.