摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
A nonvolatile memory system and a method for using programming time to reduce bit errors in the nonvolatile memory system are disclosed. The method includes programming a plurality of memory cells of a nonvolatile memory device, identifying weak cells using programming time and preventing subsequent programming to the identified weak cells.
摘要:
A nonvolatile memory system and a method for using programming time to reduce bit errors in the nonvolatile memory system are disclosed. The method includes programming a plurality of memory cells of a nonvolatile memory device, identifying weak cells using programming time and preventing subsequent programming to the identified weak cells.
摘要:
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.