A memory access module for performing memory access management of a storage device including a plurality of storage cells includes: sensing means for performing a plurality of sensing operations respectively corresponding to a plurality of different sensing voltages in order to generate at least a first digital value of a storage cell, wherein each subsequent sensing operation corresponds to a sensing voltage which is determined according to a result of the previous sensing operation; processing means for using the first digital value to obtain soft information of a bit stored in the storage cell; and decoding means for using the soft information to perform soft decoding.