Patent ID: 8665642
Filing Date: 2014-03-04
Classification: G11C

Abstract:
1. A method of operating a memory device, comprising: receiving a first set of bits and a second set of bits to be stored in a plurality of multi-level cells in the memory device; selecting a multi-level encoding from among a plurality of multi-level encodings for storing the first and second sets of bits in the plurality of multi-level cells, each multi-level encoding of the plurality of multi-level encodings including at least four encoding levels for a respective multi-level cell, respective multi-level encodings of the plurality of multi-level encodings having respective costs associated with programming the first and second sets of bits into the plurality of multi-level cells in accordance with the respective multi-level encodings, wherein the selecting is based on the respective costs of the respective encodings; and encoding the first and second sets of bits in accordance with the selected multi-level encoding to produce encoded data for storage in the memory device such that a respective multi-level cell of the plurality of multi-levels cells stores encoded data representing both a respective bit from the first set of bits and a respective bit from the second set of bits, wherein the method further comprises, prior to encoding the first and second sets of bits in accordance with the selected multi-level encoding: