CODE MODULATION ENCODER AND DECODER, MEMORY CONTROLLER INCLUDING THEM, AND FLASH MEMORY SYSTEM

摘要

Disclosed is a bit-state mapping method of a flash memory system which maps m-bit data (m being a natural number more than 2) onto one of 2m states (voltage threshold distributions). The bit-state mapping method includes performing a subset partitioning operation during first to (m-1)th levels under a condition that two adjacent states are processed as one state; and distinguishing between the adjacent states while processing an (m)th level.