Abstract: According to one embodiment, a controller is configured to write four-bit data in each of memory cells, and read first data item from the memory cells through application of a first voltage to a word line. The controller is configured to read second data items by repeating a first operation of reading data including data of respective first bits of the memory cells through application of two voltages to the word line at different timings while changing the two voltages in each first operation from the two voltages in another first operation. The controller is configured to mask part of each of the second data items using the first data.

Abstract: A memory system includes a memory device with a memory cell array including a first and second plane and first and second caches. A controller is configured to output status information in response to a status read command. The status information indicating the states of the caches. The controller begins a first process in response to a command addressed to the first plane if the status information indicates the first and second caches are in the ready state, and begins a second process on the second plane according to a second command to the second plane if the status information indicates at least the second cache is in the ready state.

Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes first blocks including a memory cell capable of storing data of one bit, a second block including a memory cell capable of storing data of two or more bits. The semiconductor memory stores first data in a first latch circuit, and second data in a second latch circuit, and writes the first data into one of the first blocks in page units, and the second data into one of the first blocks in page units. The semiconductor memory writes data of at least two pages into the second block, using the first data stored in the first latch circuit and the second data stored in the second latch circuit.

Abstract: In connection with a write operation, a memory controller transmits a first command sequence to a memory chip, thereby causing the memory chip to execute a first-stage program operation that includes a first operation and a first part of a second operation after the first operation, and a second command sequence to the memory chip after the first-stage program operation is executed, thereby causing the memory chip to execute a second-stage program operation that includes a second part of the second operation and no part of the first operation. During the first operation, a program voltage is applied a plurality of times while increasing the program voltage each of the times by a first step size. During the second operation, the program voltage is applied a plurality of times while increasing the program voltage each of the times by a second step size smaller than the first step size.

Abstract: According to one embodiment, a memory system includes a nonvolatile memory including a plurality of blocks each including a plurality of cell units, each of the cell units including a plurality of memory cells; and a memory controller. The memory controller is configured to read second data from a second cell unit in a first block in response to first data being written in a first cell unit in the first block, and reserve refresh processing for the first block when the second data satisfies a condition.

Abstract: A semiconductor memory device includes a first memory cell, a second memory cell above the first memory cell, a first word line electrically connected to a gate of the first memory cell, a second word line electrically connected to a gate of the second memory cell, and a control unit that performs an erasing operation on the first and second memory cells. During the erasing operation, the control unit applies a first voltage to a first word line and a second voltage higher than the first voltage to a second word line.

Abstract: According to one embodiment, a memory system includes a semiconductor memory device and a controller. The device includes a plurality of memory cells capable of storing at least first to third data and a word line coupled to the plurality of memory cells. The first data is determined by a first read operation including a first read level. The second data is determined by a second read operation including a second read level. The third data is determined by a third read operation including a third read level. The controller controls the semiconductor memory device to perform a forth read operation including the first and second read levels in a search operation for first to third read voltages corresponding to the first to third read levels, respectively.

Abstract: According to one embodiment, a memory system includes: a controller configured to execute an error correction process on first data read from a first area at a first address of a memory device and determine a read level used for reading data at the first address according to a result of the correction process. The controller executes the correction process on first frame data of the first data. When the correction process on the first frame data has failed, the controller executes the correction process on second frame data of the first data. When the correction process on the second frame data has succeeded, the controller determines the read level based on a result of comparison between the second frame data and a result of the correction process on the second frame data.

Abstract: According to an embodiment, a memory controller obtains first data in a first page using a first voltage, obtains a first shift amount based on a first and second number. The first and second numbers represent numbers of bits each of which has different values in a first and second manner between the first data and first expected data. The controller obtains second data in the second page using a second voltage and a second shift amount, and obtains a third shift amount based on a third and fourth number, the third and fourth numbers respectively represent numbers of bits each of which has different values in the first and second manner between the second data and second expected data.

Abstract: According to one embodiment, a semiconductor memory device includes: a memory cell configured to hold 5-bit data; a word line coupled to the memory cell; and a row decoder configured to apply first to 31st voltages to the word line. A first bit of the 5-bit data is established by reading operations using first to sixth voltages. A second bit of the 5-bit data is established by reading operations using seventh to twelfth voltages. A third bit of the 5-bit data is established by reading operations using thirteenth to eighteenth voltages. A fourth bit of the 5-bit data is established by reading operations using nineteenth to 25th voltages. A fifth bit of the 5-bit data is established by reading operations using 26th to 31st voltages.

Abstract: According to one embodiment, an information processing device includes: a first memory; a first receiver; a first determination section; and a first transmitter. The first memory is configured to store first image data of interior of a vehicle at a first point in time. The first receiver is configured to receive second image data of the interior of the vehicle at a second point of time from the vehicle. The first determination section is configured to determine whether a change has been caused in the interior of the vehicle between the first point in time and the second point in time. The first transmitter is configured to transmit first data based on the determination result.

Abstract: According to one embodiment, a memory system includes a nonvolatile semiconductor memory, and a controller. The semiconductor memory includes a memory cell, and a write circuit configured to write data to the memory cell by applying a program voltage to the memory cell and comparing a threshold voltage of the memory cell with a first reference voltage corresponding to the write data. The write circuit is configured to execute a first programming operation to obtain a value of a write parameter by comparing the threshold voltage with a second reference voltage different from the first reference voltage.

Abstract: According to one embodiment, a controller is configured to write four-bit data in each of memory cells, and read first data item from the memory cells through application of a first voltage to a word line. The controller is configured to read second data items by repeating a first operation of reading data including data of respective first bits of the memory cells through application of two voltages to the word line at different timings while changing the two voltages in each first operation from the two voltages in another first operation. The controller is configured to mask part of each of the second data items using the first data.

Abstract: According to one embodiment, a non-volatile memory includes a plurality of groups and a memory controller configured to execute a first operation. Each of the plurality of groups includes a plurality of cell units. Each of the plurality of cell units includes a plurality of memory cells. The first operation includes: based on a first correction amount associated with a target group, reading data from the target group; and updating the first correction amount to a second correction amount based on the data. The memory controller is configured to: select a first group as the target group; and when a condition is satisfied, select a second group as the target group after performing the first operation related to the first group.

Abstract: According to one embodiment, a semiconductor memory device includes: a first memory cell; a second memory cell; a first word line; a second word line; and a first bit line. The device is configured to execute a first operation, a second operation, and a third operation to write data into the first memory cell. In the first operation, a first voltage is applied to the second word line. In the second operation, after the first operation, a second voltage higher than the first voltage is applied to the second word line. In the third operation, after the second operation, a third voltage higher than the second voltage is applied to the first word line, and a fourth voltage lower than both the second voltage and the third voltage is applied to the second word line.

Abstract: According to one embodiment, a memory system includes a shift register memory and a controller. The shift register memory includes data storing shift strings. The controller changes a shift pulse, which is to be applied to the data storing shift strings from which first data is read by applying a first shift pulse, to a second shift pulse to write second data to the data storing shift strings and to read the second data from the data storing shift strings. The controller creates likelihood information of data read from the data storing shift strings in accordance with a read result of the second data. The controller performs soft decision decoding for the first data using the likelihood information.

Abstract: According to one embodiment, a memory system includes a nonvolatile semiconductor memory, and a controller. The semiconductor memory includes a memory cell, and a write circuit configured to write data to the memory cell by applying a program voltage to the memory cell and comparing a threshold voltage of the memory cell with a first reference voltage corresponding to the write data. The write circuit is configured to execute a first programming operation to obtain a value of a write parameter by comparing the threshold voltage with a second reference voltage different from the first reference voltage.

Abstract: According to one embodiment, a memory system includes: a controller configured to execute an error correction process on first data read from a first area at a first address of a memory device and determine a read level used for reading data at the first address according to a result of the correction process. The controller executes the correction process on first frame data of the first data. When the correction process on the first frame data has failed, the controller executes the correction process on second frame data of the first data. When the correction process on the second frame data has succeeded, the controller determines the read level based on a result of comparison between the second frame data and a result of the correction process on the second frame data.

Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The memory system is capable of executing a first operation and a second operation. In the first operation, the controller issues a first command sequence, the semiconductor memory applies a first voltage to a first word line and applies a second voltage to a second word line to read data from the first memory, and the read data is transmitted to the controller from the semiconductor memory. In the second operation, the controller issues a second command sequence, the semiconductor memory applies a third voltage to the first word line and applies a fourth voltage to the second word line, and data held in the memory cell array is left untransmitted to the controller.

Abstract: According to one embodiment, a memory system includes a semiconductor memory device and a controller. The device includes a plurality of memory cells capable of storing at least first to third data and a word line coupled to the plurality of memory cells. The first data is determined by a first read operation including a first read level. The second data is determined by a second read operation including a second read level. The third data is determined by a third read operation including a third read level. The controller controls the semiconductor memory device to perform a forth read operation including the first and second read levels in a search operation for first to third read voltages corresponding to the first to third read levels, respectively.