Decoding method of selecting optimized read voltage set based on gray code count deviation summations, and storage controller using the same

Abstract

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 a plurality of target memory cells of the target word-line are programmed; reading the target memory cells by respectively using different X read voltage sets, so as to obtain X Gray code count deviation summations, wherein the X read voltage sets and the corresponding X Gray code count deviation summations are all ordered based on a first predefined order; and choosing one of the X read voltage sets as an optimized read voltage set according to the X Gray code count deviation summations.