NONSEQUENTIAL ENCODING SCHEME FOR MULTILEVEL CELL (MLC) MEMORY CELLS

摘要

PURPOSE: A non-sequential encoding method for MLC(multi level cell) memory cells is provided to improve the performance of a memory array by encoding the MLC memory cells in the memory array with the non-sequential encoding method. CONSTITUTION: A non-sequential encoding method is selected to allocate different multi-bit logic values to a plurality of physical states of the selected MLC memory cell(244). Data is written in the selected MLC memory cell with regard to the selected non-sequential encoding method(246). [Reference numerals] (230) Selecting an encoding method; (232) Obtaining state transition features about a selected memory cell; (234) Selecting a first encoding method; (236) Constructing a state-logic value conversion table about a selected encoding method; (238) Performing an R/W sequence about memory cells using a selected encoding method while frequency statistics are collected and total energy consumption is measured; (240) Additional method?; (242) Selecting the following encoding method; (244) Implementing the optimum encoding method; (246) Writing data using the optimum encoding method; (248) Finish; (AA) No; (BB) Yes