According to one embodiment, a decoding device comprises a converter configured to convert read data to first likelihood information by using a first conversion table, a decoder which decodes the first likelihood information, a controller which outputs a decoding result of the decoder when the decoder succeeds decoding, and a creator module which creates a second conversion table based on the decoding result when the decoder fails decoding. When the second conversion table is created, at least a part of the decoding result is converted to second likelihood information by using the second conversion table the second likelihood information is decoded.

In one implementation, the disclosure provides a decoding system that concurrently executes a read sample combining recovery process and an iterative outer code (IOC) recovery process. Performing the read sample combining recovery process entails executing multiple rounds of logic that each provide for combining together different data samples read from a data block. The IOC recovery process is performed at least partially concurrent with the read sample combining recovery process and each round of the IOC recovery process is based on newly-updated data samples generated by the read sample combining recovery process.

A memory system including a memory device and a memory controller including a processor. The memory controller is configured to read outputs from the memory cells in response to a read command from a host and to convert the read outputs to a first codeword. The processor performs a first error correcting code (ECC) operation on the first codeword. The processor is further configured to apply, for each selected memory cell among the memory cells, a corresponding one of the read outputs and at least one related feature as input features to a machine learning algorithm to generate a second codeword, and the memory controller is configured to perform a second ECC operation on the second codeword, when the first ECC operation fails.

An optimal detection voltage obtaining method, a reading control method and an apparatus are provided. The method includes: obtain a plurality of first difference values and a plurality of second difference values, the second difference value characterizes a difference value of two detection voltages which are adjacent in numerical value, the first difference value characterizes a difference between numbers of memory cells whose threshold voltages respectively equal to the two detection voltages used by the second difference value; dividing the first difference by the second difference to obtain a plurality of tangent approximations; selecting a first tangent approximation and a second tangent approximation from the plurality of tangent approximations, the first tangent approximation is a positive number and the second tangent approximation is a negative number; calculating an optimal detection voltage according to the first tangent approximation, the second tangent approximation, a first detection voltage and a second detection voltage.

A bit interleaving method applying a bit permutation process to a QC LDPC codeword made up of N cyclic blocks of Q bits each, dividing the processed codeword into constellation words of M bits each, and applying an intra-cyclic-block permutation process to the cyclic blocks, where the codeword is divided into F×N/M folding sections of M/F cyclic blocks each and the constellation words are each associated with one of the folding sections, and the bit permutation process is applied such that the constellation words are each made up of F bits from each of M/F different cyclic blocks in the associated section, after the permutation process.

A memory system includes a nonvolatile semiconductor memory, and a controller configured to maintain a plurality of log likelihood ratio (LLR) tables for correcting data read from the nonvolatile semiconductor memory, determine an order in which the LLR tables are referred to, based on a physical location of a target unit storage region of a read operation, and carry out correcting of data read from the target unit storage region, using one of the LLR tables selected according to the determined order.

In one implementation, the disclosure provides a decoding system that concurrently executes a read sample combining recovery process and an iterative outer code (IOC) recovery process. Performing the read sample combining recovery process entails executing multiple rounds of logic that each provide for combining together different data samples read from a data block. The IOC recovery process is performed at least partially concurrent with the read sample combining recovery process and each round of the IOC recovery process is based on newly-updated data samples generated by the read sample combining recovery process.

A communication unit for performing soft-decision demodulation comprises a receiver that receives a transmitted signal conveying a first set of bits comprising k bits selected from a set of 2.sup.k possible signals. A demodulator comprises a bank of 2.sup.k correlators that detects a transmission of each possible transmitted signal, and outputs 2.sup.k magnitudes of correlator outputs, based on the detected possible transmitted signals, as a first set of inputs. A-de-mapper circuit receives the first set of inputs and determines derived from a plurality of aggregated correlator output magnitude distributions of the first set of inputs, wherein the plurality of aggregated correlator output magnitude distributions is fewer than 2.sup.2k; and calculates therefrom a first set of aposteriori soft bits comprising k soft bits. In this manner, high quality soft-decisions can be obtained in a robust and practical manner.

According to one embodiment, a memory system includes a non-volatile memory, a memory interface that reads data recorded in the non-volatile memory as a received value, a converting unit that converts the received value to first likelihood information by using a first conversion table, a decoder that decodes the first likelihood information, a control unit that outputs an estimated value with respect to the received value, which is a decoding result obtained by the decoding, when decoding by the decoder has succeeded, and a generating unit that generates a second conversion table based on a decoding result obtained by the decoding, when decoding of the first likelihood information by the decoder has failed. When the generating unit generates the second conversion table, the converting unit converts the received value to the second likelihood information by using the second conversion table, and the decoder decodes the second likelihood information.

A memory system includes a memory device and a controller. The memory device is configured to supply a read voltage into a plurality of non-volatile memory cells and transfer values obtained from the plural non-volatile memory cells. The controller is coupled to the memory device via at least one channel. The controller adjusts a level of the read voltage based on a cell difference probability (CDP) calculated from the values when a read operation to the plurality of non-volatile memory cells fails.