Patent classifications
H03M13/3723
Positioning read thresholds in a nonvolatile memory based on successful decoding
A memory controller includes an interface and a processor. The interface communicates with a plurality of memory cells, and an individual one of the plurality of memory cells stores data in multiple predefined programming levels. The processor is configured to read an Error Correction Code (ECC) code word from a group of memory cells, via the interface, using multiple read thresholds positioned between adjacent programming levels, for producing multiple readouts that contain respective numbers of errors, to derive from the code word a reference readout that contains no errors, or contains a number of errors smaller than in the code word, to calculate multiple distances between the reference readout and the respective readouts, and set a preferred read threshold based on the calculated distances, and to perform subsequent read operations for retrieving data from the plurality of memory cells, using the preferred read threshold.
Error correction circuit and method for operating the same
An error correction circuit includes a memory that stores at least one decoding parameter, a low density parity check (LDPC) decoder that includes a first variable node storing one bit of the data, receives the at least one decoding parameter from the memory, decides a degree of the first variable node based on the at least one decoding parameter, and decides a decoding rule necessary for decoding of the one bit based on the degree of the first variable node, and an adaptive decoding controller that outputs corrected data based on a decoding result of the LDPC decoder.
Vertical layered finite alphabet iterative decoding
This invention presents a method and apparatus for vertical layered finite alphabet iterative decoding of low-density parity-check codes (LDPC) which operate on parity check matrices that consist of blocks of sub-matrices. The iterative decoding involves passing messages between variable nodes and check nodes of the Tanner graph that associated with one or more sub-matrices constitute decoding blocks, and the messages belong to a finite alphabet. Various embodiments for the method and apparatus of the invention are presented that can achieve very high throughputs with low hardware resource usage and power.
Error correction method of a memory system
An error correction method includes performing a first error correction code (ECC) decoding operation of read data outputted from a memory medium and storing the read data outputted from the memory medium into a loop-buffer, in a first operation mode, and performing a second ECC decoding operation of the read data stored in the loop-buffer in a second operation mode.
Self-adaptive low-density parity check hard decoder
Disclosed are methods, systems and devices for decoding data read from a memory device, including receiving noisy data from a first memory location included in a word line zone of the memory device, identifying the word line zone and a prior successful decoder parameter associated with the word line zone, decoding the noisy data using the prior successful decoder parameter used in a prior successful decoding with respect to a second memory location included in the same word line zone, determining whether the decoding based on the prior successful decoder parameter has succeeded, maintaining, upon a determination that the decoding has succeeded, the prior successful decoder parameter as a decoder parameter for the first memory location, and decoding, upon a determination that the decoding operation has failed, the noisy data read from the first memory location by using another decoder parameter selected from a set of predefined decoder parameters.
Data storage device with syndrome weight minimization for data alignment
A memory controller that includes, in one implementation, a memory interface and a controller circuit. The memory interface is configured to interface with a non-volatile memory. The controller circuit is configured to receive a skewed codeword read from the non-volatile memory. The controller circuit is also configured to scan the skewed codeword by inserting or removing a quantity of bits at different locations in the skewed codeword and determining resulting syndrome weights of the skewed codeword. The controller circuit is further configured to determine an adjusted codeword by inserting or removing the quantity of bits at one of the different locations in the skewed codeword which results in a smallest syndrome weight. The controller circuit is also configured to decode the adjusted codeword.
DATA RECOVERY USING A COMBINATION OF ERROR CORRECTION SCHEMES
Exemplary methods, apparatuses, and systems include receiving a request for a segment of data. The requested segment data is one of a plurality of segments of data in a stripe of data. A failure to decode the requested segment is detected. Each of the plurality of segments in the stripe other than the requested segment are read. Reading each segment includes reading raw encoded data and attempting to decode the raw encoded data, the result of reading each segment including decoded data when decoding is successful and the raw encoded data when decoding fails. A combined result of each read is generated. The combining includes combining decoded data for segments that were successfully decoded and the raw encoded data for segments for which decoding failed. A statistical model for the requested segment is updated using the combined result. The requested segment is decoded using the updated statistical model.
Method and apparatus for communication
Aspects of the disclosure provide an apparatus that includes transmitting circuit and processing circuit. The transmitting circuitry is configured to transmit wireless signals. The processing circuitry is configured to encode a set of information bits with a code that is configured for incremental redundancy to generate a code word that includes the information bits and parity bits, buffer the code word in a circular buffer, determine a start position in the circular buffer based on a redundancy version that is selected from a plurality of redundancy versions based on a scenario evaluation of a previous transmission associated with the set of information bits, and transmit, via the transmitting circuitry, a selected portion of the code word from the start position.
DECODING APPARATUS, CONTROL CIRCUIT, AND STORAGE MEDIUM
A decoder that is a decoding apparatus includes an error-correction decoder that executes error correction decoding processing of iteratively performing decoding processing with a window size and the number of decoding iterations indicated by decoding parameters, on received data converted into a spatially coupled low-density parity-check code, and a decoding parameter control unit that updates the decoding parameters on the basis of a decoding result obtained by the iteratively executed decoding processing.
Method and Apparatus for Vertical Layered Decoding of Quasi-Cyclic Low-Density Parity Check Codes Using Predictive Magnitude Maps
A method and apparatus for decoding quasi-cyclic LDPC codes using a vertical layered iterative message passing algorithm. The algorithm of the method improves the efficiency of the check node update by using one or more additional magnitudes, predicted with predictive magnitude maps, for the computation of messages and update of the check node states. The method allows reducing the computational complexity, as well as the storage requirements, of the processing units in the check node update. Several embodiments for the apparatus are presented, using one or more predictive magnitude maps, targeting significant savings in resource usage and power consumption, while minimizing the impact on the error correction performance loss.