Abstract: A storage device is provided as follows. A nonvolatile memory device includes blocks, each block having sub-blocks erased independently. A memory controller performs a garbage collection operation on the nonvolatile memory device by selecting a garbage collection victim sub-block among the sub-blocks and erasing the selected garbage collection victim sub-block to generate a free sub-block. The memory controller selects the garbage collection victim sub-block using valid page information of each sub-block and valid page information of memory cells adjacent to each sub-block.

Abstract: A method of decoding may include performing fewer than ? 2 k - 1 k ? number of sensing operations of multilevel cells within a nonvolatile memory device, decoding pages corresponding to each of the sensing operations while correcting a channel error using an RIO code, and extracting user data from the decoded pages.

Abstract: A method of operating a memory system, having a non-volatile memory device, includes processing a response to a first request toward the memory device by using an original key, in response to the first request, generating and storing first parity data corresponding to the original key, and deleting the original key.

Abstract: A method of setting a read voltage by a memory controller and a storage device are provided. The method includes controlling a memory device to read data from memory cells by applying a test read voltage to a selected word line; receiving, from the memory device, cell count information corresponding to a read operation of the memory device, and renewing the test read voltage by using the cell count information and a cost function to find an optimum read voltage, the cost function being determined for each read voltage level; and determining a read voltage by performing the controlling of the memory device and the renewing of the test read voltage at least once.

Abstract: A method of operating a memory controller includes classifying a plurality of memory cells in an erase state into a plurality of groups, based on erase state information about the plurality of memory cells in the erase state; setting at least one target program state for at least some memory cells from among memory cells included in at least one of the plurality of groups; and programming the at least some memory cells for which the at least one target program state has been set, to a program state other than the at least one target program state from among the plurality of program states.

Abstract: An method of operating a nonvolatile memory device including a plurality of memory cells comprises receiving a read command from an external device, in response to the read command, performing, based on a reference voltage, a first cell counting operation with respect to the plurality of memory cells, adjusting at least one read voltage of first through nth read voltages (where n is a natural number greater than 1) based on a first result of the first cell counting operation, and performing, based on the adjusted at least one read voltage, a read operation corresponding to the read command with respect to the plurality of memory cells.

Abstract: A low-density parity check (LDPC) decoder may include a variable node processing unit and a check node processing unit. The check node processing unit includes memory elements storing a check node value. The memory elements are interconnected through two or more paths, and each of the paths may include a total or partial cyclic permutation of the memory elements to transmit the check node value.

Abstract: A method of operating a memory controller includes classifying a plurality of memory cells in an erase state into a plurality of groups, based on erase state information about the plurality of memory cells in the erase state; setting at least one target program state for at least some memory cells from among memory cells included in at least one of the plurality of groups; and programming the at least some memory cells for which the at least one target program state has been set, to a program state other than the at least one target program state from among the plurality of program states.

Abstract: An error correction device includes a low density parity check (LDPC) decoder and an adaptive decoding controller. The LDPC decoder iteratively performs LDPC decoding on data by using a decoding parameter. The adaptive decoding controller calculates an error rate depending on a result of the LDPC decoding and adjusts the decoding parameter depending on the error rate.

Abstract: A method of operating a memory controller that performs decoding by using a parity check matrix corresponding to a convolution-type low density parity check (LDPC) code includes receiving a codeword from at least one memory device, the codeword including a first sub-codeword and a second sub-codeword; decoding a first sub-codeword into first data by using first sliding windows in a first direction, set based on a first sub-matrix included in the parity check matrix and associated with the first sub-codeword; and decoding a second sub-codeword into second data by using second sliding windows in a second direction, set based on a second sub-matrix included in the parity check matrix and associated with the second sub-codeword.

Abstract: A decoder includes a channel mapper configured to generate a plurality of channel reception values based on hard decision information and soft decision information, a strong error detector configured to determine whether a strong error has occurred using a plurality of check node messages and the channel reception values and to correct the channel reception values according to a determination result to produce corrected channel reception values, a variable node unit configured to generate a plurality of variable node messages using the check node messages and the corrected channel reception values, and a check node unit configured to generate the check node messages using the variable node messages. The variable node unit includes a plurality of variable nodes and the check node unit includes a plurality of check nodes.

Abstract: A method of decoding a low density parity check (LDPC) code, includes dividing a parity check matrix of the LDPC code, into a plurality of sub blocks. The method further includes, for each of a plurality of decoding iterations, performing a node operation of each of target sub blocks among the plurality of sub blocks, the target sub blocks corresponding to a present decoding iteration among the plurality of decoding iterations, in a decoding schedule, estimating a reliability of each of the target sub blocks, based on a result of the node operation of each of the target sub blocks, and adjusting the decoding schedule, based on the reliability of each of the target sub blocks.

Abstract: A polar code encoding and decoding method includes generating a first and second sub-codewords. The sub-codewords correspond to pre-codewords, and the pre-codewords have a shared data aspect. The sub-codewords provide useful error-recovery for data stored in a memory. When data is read from the memory, decoding takes place. The data read operation may include hard decision decoding, soft decision decoding, or hard decision decoding followed by soft decision decoding. In the method, the shared data aspect is used to decode a first sub-codeword for which decoding was not initially successful. An apparatus is also provided.

Abstract: A method of operating a decoder, which has variable nodes and check nodes, includes receiving variable-to-check (V2C) messages from the variable nodes using a first check node among the check nodes. The number of messages having a specific magnitude among the V2C messages is counted. The magnitude of a check-to-variable (C2V) message to be transmitted to a first variable node, among the variable nodes, is determined based on the count value and the magnitude of a V2C message of the first variable node.

Abstract: A decoder including a main memory, a flag memory and a decoding logic is provided. The flag memory is configured to store flag data and the decoding logic configured to perform an iteration. Further, the decoding logic is configured to: perform an ith operation using first data, wherein i is a natural number, flag-encode second data that is results obtained by performing the ith operation on the first data, store results obtained by performing the flag encoding on the second data in the flag memory as first flag data if the flag encoding succeeds, and store predetermined second flag data that is different from the first flag data of the second data in the flag memory if the flag encoding fails.

Abstract: A display device includes a display unit including pixels, a memory to store degradation data of the pixels, a group-setting portion to classify the pixels into degradation regions according to a degradation degree and based on the degradation data, perform a contour-simplifying process with respect to the degradation regions, classify the degradation regions into labeling regions according to proximity of adjacent ones of the degradation regions, and set one of the degradation regions as a reference region, a sensor to sense electric characteristics of the degradation regions and the reference region as they separately emit light, a compensation amount controller to compare the electric characteristics of the degradation regions with electric characteristics of the reference region, and calculate a per-position compensation data corresponding to a position of the labeling regions, and a converter to convert a first image data into a second image data based on the per-position compensation data.

Abstract: A nonvolatile memory storage system includes a plurality of memory cells and a memory controller configured to transmit a read command to a nonvolatile memory device based on a plurality of read voltages. The nonvolatile memory device performs a first read operation on a first level among the N levels based on a first read voltage among the plurality of read voltages, counts the number of on-cells that respond to the first read voltage among the plurality of memory cells, and adjusts a level of a second read voltage to be used to perform a second read operation on the first level or a second level among the N levels among the plurality of read voltages according to a comparison result of the counted number of on-cells and the number of reference cells.

Abstract: A method of operating a resistive memory system including a plurality of layers may include receiving a write request and first data corresponding to a first address, converting the first address into a second address and assigning n (n is an integer equal to or larger than 2) pieces of sub-region data generated from the first data to the plurality of layers, and writing the n pieces of sub-region data to at least two layers according to the second address.

Abstract: A method of operating a decoder, which has variable nodes and check nodes, includes receiving variable-to-check (V2C) messages from the variable nodes using a first check node among the check nodes. The number of messages having a specific magnitude among the V2C messages is counted. The magnitude of a check-to-variable (C2V) message to be transmitted to a first variable node, among the variable nodes, is determined based on the count value and the magnitude of a V2C message of the first variable node.

Abstract: A method of operating a memory controller includes classifying a plurality of memory cells in an erase state into a plurality of groups, based on erase state information about the plurality of memory cells in the erase state; setting at least one target program state for at least some memory cells from among memory cells included in at least one of the plurality of groups; and programming the at least some memory cells for which the at least one target program state has been set, to a program state other than the at least one target program state from among the plurality of program states.