Abstract: A memory controller includes a processor, which is configured to determine one of a first operation mode and a second operation mode as an operation mode based on a lifespan or retention of a memory device. The processor is configured to transmit to the memory device, a read command for obtaining hard decision (HD) data and a first piece of SD data during a time period of a single read, or a read command for obtaining a second piece of SD data from a plurality of reads. A decoding circuit is configured to perform iterative decoding based on the first piece of SD data or the second piece of SD data. The first operation mode is for sequentially transmitting the coarse SD read command and the fine SD read command to the memory device, whereas the second operation mode is for transmitting the fine SD read command.

Abstract: Disclosed is a storage device which includes a nonvolatile memory device, and a memory controller that performs a read operation on the nonvolatile memory device and performs an error correction operation on data read in the read operation. In the error correction operation, the memory controller estimates an error rate of the read data, and determines whether to perform a read retry operation based on the estimated error rate.

Abstract: Disclosed is a method of operating a storage controller which is configured to communicate with a non-volatile memory device. The method includes receiving count data from the non-volatile memory device, determining a pre-read voltage based on the count data, sending a pre-read request using the pre-read voltage to the non-volatile memory device, receiving pre-read data from the non-volatile memory device responsive to sending the pre-read request, calculating a decoding value corresponding to the pre-read data, and generating read voltage information based on the count data and the decoding value, and the decoding value predicts an error voltage of the pre-read data.

Abstract: Provided are a method of decoding an LDPC code for producing several different decoders using a parity-check matrix of the LDPC code, and an LDPC code system including the same. The system includes: an LDPC encoder outputting an LDPC codeword through a channel; a first LDPC decoder decoding the LDPC codeword received through the channel, and when the decoding has failed in a second LDPC decoder, decoding the LDPC codeword according to original parity check matrix of the LDPC codeword, using soft information newly generated after the decoding is ended in the second LDPC decoder; and the second LDPC decoder, when the decoding has failed in the first LDPC decoder, receiving the soft information on each bit from the first LDPC, and decoding the LDPC codeword according to a new parity-check matrix produced from the parity-check matrix of the LDPC codeword using the received soft information on each bit.

Abstract: Provided are a method of decoding an LDPC code for producing several different decoders using a parity-check matrix of the LDPC code, and an LDPC code system including the same. The system includes: an LDPC encoder outputting an LDPC codeword through a channel; a first LDPC decoder decoding the LDPC codeword received through the channel, and when the decoding has failed in a second LDPC decoder, decoding the LDPC codeword according to original parity check matrix of the LDPC codeword, using soft information newly generated after the decoding is ended in the second LDPC decoder; and the second LDPC decoder, when the decoding has failed in the first LDPC decoder, receiving the soft information on each bit from the first LDPC, and decoding the LDPC codeword according to a new parity-check matrix produced from the parity-check matrix of the LDPC codeword using the received soft information on each bit.