Patent attributes
A decoding method and a storage controller for a rewritable non-volatile memory module are provided. The method includes: choosing a target word line among a plurality of word lines, wherein preset data is programmed into a plurality of target memory cells of the target word-line; identifying a plurality of preset bit values according to the preset data; respectively using different X read voltage sets to read the target memory cells to obtain X read bit value sets respectively corresponding to the X read voltage sets, and obtain X deviation amount summation sets by comparing the X read bit value sets and the preset bit values; and determining N−1 optimized read voltages of an optimized read voltage set according to the X deviation amount summation sets.