Abstract: A method of correcting data stored in a memory device includes: applying an iterative decoder to the data; determining a total number of rows in first data the decoder attempted to correct; estimating first visible error rows among the total number that continue to have an error after the attempt; estimating residual error rows among the total number that no longer have an error after the attempt; determining second visible error rows in second data of the decoder that continue to have an error by permuting indices of the residual error rows according to a permutation; and correcting the first data using the first visible error rows.

Abstract: A method of correcting data stored in a memory device includes: applying an iterative decoder to the data; determining a total number of rows in first data the decoder attempted to correct; estimating first visible error rows among the total number that continue to have an error after the attempt; estimating residual error rows among the total number that no longer have an error after the attempt; determining second visible error rows in second data of the decoder that continue to have an error by permuting indices of the residual error rows according to a permutation; and correcting the first data using the first visible error rows.

Abstract: A method of correcting data stored in a memory device includes: applying an iterative decoder to the data; determining a total number of rows in first data the decoder attempted to correct; estimating first visible error rows among the total number that continue to have an error after the attempt; estimating residual error rows among the total number that no longer have an error after the attempt; determining second visible error rows in second data of the decoder that continue to have an error by permuting indices of the residual error rows according to a permutation; and correcting the first data using the first visible error rows.

Abstract: A memory system includes a memory controller; and a memory device, the memory device including a memory cell array, the memory cell array including least a first memory page having a plurality of memory cells storing a plurality of stored bits, the memory controller being such that, the memory controller performs a first hard read operation on the first memory page to generate a plurality of read bits corresponding to the plurality of stored bits, and if the memory controller determines to change a value of one of a first group of bits, from among the plurality of read bits, the memory controller selects one of the first group of bits based on log likelihood ratio (LLR) values corresponding, respectively, to each of the first group of bits, and changes the value of the selected bit.

Abstract: A method of correcting values errantly attributed to bits of error correction code (ECC) blocks during a read operation. The method includes, upon determining that an error exists in the jth bit of one or more of the ECC blocks: 1) retrieving an estimate of the voltage value stored by the nonvolatile memory cell corresponding to the jth bit of each of the ECC blocks having errant data; 2) identifying, among the voltage value estimates retrieved in operation (1), an ECC block whose corresponding voltage value estimate retrieved in operation (1) is closest to the voltage value of a decision boundary for determining whether to assign a bit value of “0” or “1” to the jth bit of the ECC blocks; and 3) inverting the value of the jth bit of the ECC block identified in operation (2).

Abstract: A memory system includes a memory controller; and a memory device, the memory device including a memory cell array, the memory cell array including least a first memory page having a plurality of memory cells storing a plurality of stored bits, the memory controller being such that, the memory controller performs a first hard read operation on the first memory page to generate a plurality of read bits corresponding to the plurality of stored bits, and if the memory controller determines to change a value of one of a first group of bits, from among the plurality of read bits, the memory controller selects one of the first group of bits based on log likelihood ratio (LLR) values corresponding, respectively, to each of the first group of bits, and changes the value of the selected bit.

Abstract: A method of programming a non-volatile memory device includes; defining a set of verification voltages, setting a maximum verification voltage among verification voltages that are less than or equal to a first target programming voltage to be a target verification voltage, calculating a number of extra pulses based on the target verification voltage and the first target programming voltage, verifying whether a threshold voltage of the memory cell is equal to or greater than the target verification voltage by applying an incremental step pulse program (ISPP) pulse to the memory cell and then applying at least one verification voltage in the set of verification voltages to the memory cell, and further applying the ISPP pulse to the memory cell a number of times equal to the number of extra pulses when the threshold voltage is verified to be equal to or greater than the target verification voltage.

Abstract: A low-density parity-check (LDPC) decoding method includes exchanging messages between check nodes and variable nodes based on scheduling information representing an order of exchanging messages between the check nodes and the variable nodes for an LDPC decoding, and performing the LDPC decoding based on the exchanged messages, wherein the scheduling information is determined by manipulating at least one of an order of the check nodes and an order of the variable nodes in an LDPC bipartite graph.

Abstract: A method of programming a non-volatile memory device includes; defining a set of verification voltages, setting a maximum verification voltage among verification voltages that are less than or equal to a first target programming voltage to be a target verification voltage, calculating a number of extra pulses based on the target verification voltage and the first target programming voltage, verifying whether a threshold voltage of the memory cell is equal to or greater than the target verification voltage by applying an incremental step pulse program (ISPP) pulse to the memory cell and then applying at least one verification voltage in the set of verification voltages to the memory cell, and further applying the ISPP pulse to the memory cell a number of times equal to the number of extra pulses when the threshold voltage is verified to be equal to or greater than the target verification voltage.