An operating method of a controller includes: a first step of generating an internal codeword including an ECC unit data and an internal parity code by performing ECC decoding operation to an input data; a second step of updating an external parity code based on the ECC unit data, which is included in the internal codeword currently generated, and the ECC unit data, which is included in the internal codeword previously generated; and a third step of storing in a semiconductor memory device one or more internal codewords and the updated external parity code, which are generated through repetition of the first and second steps, by a unit of predetermined storage size.

A soft input decoding method and a decoder for generalized concatenated (GC) codes. The GC codes are constructed from inner nested block codes, such as binary Bose-Chaudhuri-Hocquenghem, BCH, codes and outer codes, such as Reed-Solomon, RS, codes. In order to enable soft input decoding for the inner block codes, a sequential stack decoding algorithm is used. Ordinary stack decoding of binary block codes requires the complete trellis of the code. In one aspect, the present invention applies instead a representation of the block codes based on the trellises of supercodes in order to reduce the memory requirements for the representation of the inner codes. This enables an efficient hardware implementation. In another aspect, there is provided a soft input decoding method and device employing a sequential stack decoding algorithm in combination with list-of-two decoding which is particularly well suited for applications that require very low residual error rates.

In various embodiments, a method of using a memory device is provided. The method may include storing data units, check units of a first code and check units of a second code in memory cells of the memory device, wherein the data units and the check units of the first code form code words of the first code, and wherein the data units and the check units of the second code form code words of the second code, applying the second code for error correction in at least a portion of the data units and/or in at least a portion of the check units of the first code, after the correcting the errors, retaining at least a retaining portion of the data units and of the check units of the first code and deleting at least a deleting portion of the check units of the second code, thereby freeing the memory cells that are occupied by the deleting portion of the check units of the second code, and during a subsequent using of the memory device, storing data in at least a reuse portion of the freed-up memory cells.

Described is an apparatus which comprises: a first encoder to encode data with a first error correction scheme to generate a set of codewords, each codeword of the set having a data portion and a corresponding parity portion, and each codeword of the set to be stored in a separate memory bank of a memory block; and a second encoder to encode the data portions of each codeword of the set with a second error correction scheme, the second encoder to generate a combined codeword having a data portion and a corresponding parity portion, wherein the corresponding parity portion of the combined codeword is to be stored in an additional memory bank of the memory block.

An operating method of a controller includes generating error reliability of data based on reliability information of one or more error-corrected bits of the data, wherein the data is read out from a semiconductor memory device and a hard decision ECC decoding to the data through a BCH code is determined as successful; and determining miscorrection of the data based on the error reliability.

Various implementations described herein relate to systems and methods for encoding and decoding data having input payload stored in a non-volatile storage device, including encoding the input payload by concatenating a plurality of short codewords to generate a plurality of encoded short codewords, and decoding the plurality of encoded short codewords to obtain the data, where each of the plurality of short codewords corresponding to a portion of the input payload.

A memory system that detects and corrects bit errors performs a first decoding procedure regarding a serial unit of the encoded data to produce a decoded serial unit. The memory system further determines the first decoding procedure regarding the serial unit was not successful and performs the first decoding procedure regarding a plurality of additional serial units of the encoded data to produce a plurality of additional decoded serial units. The serial unit and the plurality of additional serial units constitute a predefined grouping of the encoded data. The memory system also performs a second decoding procedure regarding a plurality of derivative units to produce a plurality of decoded derivative units. Each successive bit in each of the plurality of derivative units is correlated to a corresponding sequential position in the decoded serial unit and each of the decoded additional serial units.

A non-volatile memory system may include a tracking module that tracks logic values of bits to be stored in memory elements identified as unreliable. A record of the logic values may be generated. During decoding of the data, a log likelihood ratio module may use the record to assign log likelihood ratio values for the decoding.

An encryption module encrypts starting data using a random key to produce encrypted data. A hash module performs a secure hash function on the encrypted data using a secret key to produce a hash value. Processing circuitry masks the random key using the hash value to produce a masked random key, and combines the encrypted data and the masked random key to produce a secure package. A distributed storage and task module encodes the secure package to produce a set of encoded data slices. The secret key and a decode threshold number of the encoded data slices included in the set of encoded data slices are sufficient to recover the secure package and the starting data. The set of encoded data slices is stored in a set of storage units.

A data storage device includes a nonvolatile memory device including a target memory region; and a controller suitable for performing a read operation by reading a data chunk from the target memory region based on a read bias and performing an error correction operation for the data chunk, iterating the read operation according to a result of the error correction operation, and adjusting the read bias based on at least one read bias used in one or more previous read operations and at least one correction failure index corresponding to the at least one read bias.