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 a first digital value and a second digital value of a storage cell; processing means for using the first digital value and the second digital value to obtain soft information of a same bit stored in the storage cell; decoding means for using the soft information to perform soft decoding; and controlling means for accessing the storage device. The controlling means includes: storage means for storing a program code; and processing means for executing a program code to control access to the storage device and manage the plurality of storage cells.