Abstract: A nonvolatile memory storage controller for delivering log likelihood ratios (LLRs) to a low-density parity check (LDPC) decoder for use in the decoding of an LDPC encoded codeword. The controller includes partitioning circuitry for identifying a set of soft-decision reference voltages having the smallest calculated introduced error value based upon the estimated BER of the nonvolatile memory. The controller further includes read circuitry for reading an LDPC encoded codeword stored in a nonvolatile memory storage module using the set of soft-decision reference voltages having the smallest calculated LLR introduced error value to provide a plurality of soft-decision bits representative of the codeword. The controller further includes an LLR look-up table accessible by the read circuitry to provide LLRs to the LDPC decoder for the subsequent decoding of the codeword.

Abstract: A system and method for memory block pool wear leveling in a nonvolatile memory device. An improved bit error rate for the nonvolatile memory system is attained by identifying a plurality of memory block pools of the nonvolatile memory system, identifying a relaxation time delay for each of the plurality of memory block pools and executing a predetermined number of program/erase cycles for each of the plurality of memory block pools based upon the relaxation time delay of the memory block pools.

Abstract: Apparatuses and methods for correcting errors in data read from memory cells of an integrated circuit device includes an encoder. The encoder is configured from a single parity check matrix and the encoder is configured to be virtually adjustable by setting a number of bits in the encoder to zero. A decoder is configured from the single parity check matrix and the decoder is configured to be virtually adjustable by setting a log-likelihood ratio (LLR) for a number of bits in the decoder to a strong value. A code-rate that the encoder and decoder uses can be changed by adjusting the number of bits in the encoder that are set to zero and the number of bits in the decoder that are set to the strong LLR value.

Abstract: Systems and methods for correcting errors in data read from memory cells include a memory controller, which includes an encoder, and a decoder. The memory controller is configured to adjust a correctable raw bit error rate limit to correct different bit error rates occurring in data read from the memory cells. The correctable raw bit error rate limit is adjusted by switching the decoding between hard-decision decoding and soft-decision decoding, wherein a number of soft bits allocated for message values can be changed during soft-decision decoding. The correctable raw bit error rate is adjusted by changing the code-rate within the memory system while making virtual adjustments to the same encoder and decoder.

Abstract: A low-density parity check (LDPC) decoder is provided for decoding low-density parity check (LDPC) encoded data wherein a layer specific attenuation factor is provided for each layer of the LDPC parity check matrix. An attenuation factor matrix comprising a plurality of coefficients specifies the specific attenuation factor for each layer and each iteration of the decoding process. A check node processor performs check node processing for each layer of the parity check matrix associated with the LDPC encoded codeword utilizing the normalized layered min-sum algorithm wherein the attenuation factor of the min-sum algorithm is determined by the coefficients of the attenuation factor matrix.

Abstract: A method and system for making error corrections on digital information coded as symbol sequences, for example digital information stored in electronic memory systems or transmitted from and to these systems is described, provides the transmission of sequences incorporating a portion of error corrector code allowing the sequence which is more probably the original transmitted through the calculation of an error syndrome using a parity matrix to be restored when received. Advantageously according to embodiments of the invention, the error code incorporated in the original sequence belongs to a non Boolean group.

Abstract: A nonvolatile memory storage controller for delivering log likelihood ratios (LLRs) to a low-density parity check (LDPC) decoder for use in the decoding of an LDPC encoded codeword. The controller includes partitioning circuitry for identifying a set of soft-decision reference voltages having the smallest calculated introduced error value based upon the estimated BER of the nonvolatile memory. The controller further includes read circuitry for reading an LDPC encoded codeword stored in a nonvolatile memory storage module using the set of soft-decision reference voltages having the smallest calculated LLR introduced error value to provide a plurality of soft-decision bits representative of the codeword. The controller further includes an LLR look-up table accessible by the read circuitry to provide LLRs to the LDPC decoder for the subsequent decoding of the codeword.

Abstract: A system and method reading, accumulating and processing soft information for use in LDPC decoding. In accordance with the present invention, an LDPC decoder includes accumulation circuitry to receive soft reads of a cell of the nonvolatile memory storage module and to produce an accumulated soft read that can be used to identify an appropriate LLR for the cell. The accumulation circuitry of the present invention may include, an accumulation RAM, an arithmetic logic unit (ALU) and a soft accumulation control and sequencing module for accumulating and processing soft information for use in LDPC decoding.

Abstract: A nonvolatile memory storage controller is provided for delivering log likelihood ratios (LLRs) to a low-density parity check (LDPC) decoder for use in the decoding of an LDPC encoded codeword. The controller includes read circuitry for reading an LDPC encoded codeword stored in a nonvolatile memory storage module using a plurality of soft-decision reference voltages to provide a plurality of soft-decision bits representative of the codeword. The controller further includes a plurality of neighboring cell contribution LLR look-up tables representative of the contribution of the neighboring cells to threshold voltage distribution of the memory storage module. The controller provides the LLRs from the appropriate LLR look-up table to an LDPC decoder for the subsequent decoding of the codeword.

Abstract: A nonvolatile memory controller generates an error correction code for each data unit in a data stripe and generates a parity unit based on the data units of the data stripe. If a data unit of the data stripe has a number of data bit errors not exceeding the error correction capacity of the nonvolatile memory controller, the nonvolatile memory controller corrects any data bit errors in the data unit based on the error correction code of the data unit. Otherwise, if a data unit of the data stripe has a number of data bit error exceeding the error correction capacity of the nonvolatile memory controller, the nonvolatile memory controller recovers the data unit based on the other data units of the data stripe and the parity unit.

Abstract: A data storage device reads a data unit from a memory page, detects a number of data bit errors in the data unit, and generates a bit error indicator identifying bit indexes of the data bit errors in the data unit. The data storage device reads the data unit from the memory page once again and generates a corrected data unit by correcting data bit errors in the data unit based on the error correction code if the number of data bit errors in the data unit does not exceed an error correction capacity of the error correction code. Otherwise, the data storage device generates a modified data unit based on the data unit by negating at least one erroneous data bit the data unit based on the bit error indicator and corrects any remaining data bit errors in the modified data unit based on the error correction code.

Abstract: A data storage device stores a data unit in a memory page of a storage block along with an error correction code unit for the data unit. Additionally, the data storage device stores an error correction code unit for the data unit in a memory page of another storage block. In various embodiments, one or both of the error correction code units form an error correction code for correcting data bit errors in the data unit. Because the memory page containing the data unit does not have a storage capacity for simultaneously storing the error correction code and the data unit, the data storage device is capable of correcting a greater number of data bit errors in the data unit by using the error correction code in comparison to using an error correction code that would fit in the memory page.

Abstract: A nonvolatile memory controller may recover encoded data using the outer error correction code of the encoded data if it is determined that a correction capacity of the outer error correction code is not exceeded. Alternatively, the nonvolatile memory controller may recover the encoded data using the inner error correction code of the encoded data followed by the outer error correction code of the encoded data if it is determined that the correction capacity of the outer error correction code is exceeded. Additionally, if it is determined that the correction capacity of the outer error correction code is exceed after recovering the data using the inner error correction code, the nonvolatile memory storage module may perform a redundant array of independent disks (RAID) operation to recover the data.

Abstract: A nonvolatile memory controller to recover encoded data by performing a hard-decision inner error correction code decoding and an outer error correction code decoding of the data decoded using the hard-decision inner error correction code decoding and then determining if the encoded data has been successfully decoded. If the encoded data has not been successfully decoded, the controller performs a soft-decision inner error correction code decoding of the encoded data using a soft-decision algorithm and an outer error correction code decoding of the data decoded using the soft-decision inner error correction code decoding and then determining if the encoded data has been successfully decoded. If the encoded data has not been successfully decoded, the controller recovers the data by performing a RAID operation on the encoded data.

Abstract: In various embodiments, a data correction system has a data path including search modules. Each of the search modules has a respective bit error capacity for locating a number of data bit errors in a data unit based on a locator polynomial. The data correction system generates a syndrome based on an input data unit, generates a locator polynomial based on the syndrome, and determines a number of data bit errors in the input data unit based on the locator polynomial. Additionally, the data correction system selects one of the search modules having a bit error capacity of at least the number of data bit errors in the input data unit. The selected search module generates an error indicator based on the locator polynomial. The data correction system corrects each data bit error in the input data unit based on the error indicator.

Abstract: A reading method for a memory device with error-correcting encoding envisages the steps of: carrying out a first reading of a plurality of memory locations (A0, A1, . . . , ALS-1) to generate a first recovered string (S1), and performing a first decoding attempt using the first recovered string (S1). When the first decoding attempt fails, the memory locations are read at least one second time, and at least one second recovered string (S2-SN) is generated. On the basis of a comparison between the first recovered string (S1) and the second recovered string (S2-SN), a modified string (SM) is generated, in which erasures (X) are located, and at least one second decoding attempt is carried out using the modified string (SM).

Abstract: A reading method for a memory device with error-correcting encoding envisages the steps of: carrying out a first reading of a plurality of memory locations (A0, A1, . . . , ALS-1) to generate a first recovered string (S1), and performing a first decoding attempt using the first recovered string (S1). When the first decoding attempt fails, the memory locations are read at least one second time, and at least one second recovered string (S2-SN) is generated, On the basis of a comparison between the first recovered string (S1) and the second recovered string (S2-SN), a modified string (SM) is generated, in which erasures (X) are located, and at least one second decoding attempt is carried out using the modified string (SM).

Abstract: A reading method for a memory device with error-correcting encoding envisages the steps of: carrying out a first reading of a plurality of memory locations (A0, A1, . . . , ALS?1) to generate a first recovered string (S1), and performing a first decoding attempt using the first recovered string (S1). When the first decoding attempt fails, the memory locations are read at least one second time, and at least one second recovered string (S2-SN) is generated. On the basis of a comparison between the first recovered string (S1) and the second recovered string (S2-SN), a modified string (SM) is generated, in which erasures (X) are located, and at least one second decoding attempt is carried out using the modified string (SM).

Abstract: A method and system for making error corrections on digital information coded as symbol sequences, for example digital information stored in electronic memory systems or transmitted from and to these systems is described, provides the transmission of sequences incorporating a portion of error corrector code allowing the sequence which is more probably the original transmitted through the calculation of an error syndrome using a parity matrix to be restored when received. Advantageously according to embodiments of the invention, the error code incorporated in the original sequence belongs to a non Boolean group.

Abstract: Basic redundancy information is non-volatily stored in a reserved area of an addressable area of a memory array, and is copied to volatile storage therein at every power-on of the memory device. The unpredictable though statistically inevitable presence of failed array elements in such a reserved area of the memory array corrupts the basic redundancy information established during the test-on wafer (EWS) phase of the fabrication process. This increases the number of rejects, and lowers the yield of the fabrication process. This problem is addressed by writing the basic redundancy data in the reserved area of the array with an ECC technique using a certain error correction code. The error correction code may be chosen among majority codes 3, 5, 7, 15 and the like, or the Hamming code for 1, 2, 3 or more errors, as a function of the fail probability of a memory cell as determined by the EWS phase during fabrication.