A flash memory device includes a memory cell array connected with word lines and control logic that performs threshold voltage compensation on the word lines through a data recover read operation. When a word line on which programming is performed after a selected word line is a dummy word line, the control logic performs the threshold voltage compensation on the selected word line based on a result of a data recover read operation of a word line on which programming is performed before the selected word line. When a next word line on which programming is performed after a selected word line is a dummy word line, the control logic performs threshold voltage compensation on the selected word line based on a result of performing the data recover read operation on a previous word line on which programming is performed before the selected word line.

A page buffer circuit includes a sensing latch circuit and a caching latch circuit. The sensing latch circuit is configured to receive and sense data that is stored in a memory cell during a normal read operation. The caching latch circuit is configured to receive and sense the data that is stored in the memory cell during a suspend read operation.

According to one embodiment, a memory device is configured to execute an efficient read operation is provided. The memory device includes a plurality of memory cells, a word line, and a controller. Each of the memory cells stores first to fifth bit data based on the threshold voltage. The memory cells store a first page to a fifth page respectively corresponding to the first bit data to the fifth bit data. A word line is coupled to the memory cells. A controller executes a read operation for reading data from the memory cells by applying a read voltage to the word line. Numbers of times the controller applies read voltages different from one another to the word line in read operations for the first page to the fifth page are 7, 6, 6, 6, and 6, respectively.

A semiconductor memory device includes a first memory cell for storing data using at least three levels of threshold voltages, including a first level, a second level higher than the first level and a third level higher than the second level. A first word line is connected to the first memory cell. In writing of data to the first memory cell from a state where a threshold voltage of the first memory cell is the first level, a plurality of program operations and verify operations are performed, each program operation including applying a program voltage to the first word line, each verify operation including applying a read voltage lower than the program voltage. The program operations include a program operation for the second level and a program operation for the third level, and the verify operations include a verify operation for the second level, and do not include a verify operation for the third level.

A semiconductor memory device includes i first word lines connected to the i first memory cells, i second word lines connected to the i second memory cells, a driver capable of supplying voltage to each of the i first word lines and each of the i second word lines, and a logic control circuit controlling both a write operation including a verify operation and a read operation including a verify operation. In the semiconductor memory device, when an order of performing a sense operation for determining whether or not a threshold voltage of the k-th first memory cell has reached a j-th threshold voltage in the verify operation is different from that of in the read operation, a voltage applied to the k-th first word line in the verify operation is different from a voltage applied to the k-th first word line in the read operation.

At least one address scheduling method includes selecting a first bit line, selecting a first string connected to the first bit line, performing address scheduling on N pages of each of multi-level cells in the first string sequentially from a bottom word line to a top word line, and after completing the address scheduling on all word lines in the first string, performing address scheduling on second to k-th strings sequentially in the same manner as performed with respect to the first string, where “k” is 2 or a natural number greater than 2.

A nonvolatile memory device includes memory cells, bit lines, a word line, and a control unit performing a write operation in first and second stages. During the first stage, the control unit applies voltages to the word line and the bit lines based on first page of data to maintain threshold voltages for a first group of memory cells and shift the threshold voltages for a second group of memory cells above a first threshold. During the second stage, the control unit applies voltages to the word line and the bit lines based on second and third pages of data to shift the threshold voltages of memory cells in the first group to threshold voltages in one of first, second, and third threshold voltage ranges and the threshold voltages of memory cells in the second group to threshold voltages in one of fourth, fifth, sixth, and seventh threshold voltage ranges.

An operating method of a memory device, which includes a first memory region and a second memory region, includes reading first data from the first memory region and storing the read first data in a data buffer block, performing a first XOR operation on the first data provided from the data buffer block and second data read from the second memory region to generate first result data, writing the first data stored in the data buffer block in the second memory region, performing a second XOR operation on the first data and the first result data to generate the second data, storing the generated second data in the data buffer block, and writing the second data stored in the data buffer block in the first memory region.

Data storage circuits are connected to the bit lines in a one-to-one correspondence. A write circuit writes the data on a first page into a plurality of 5 first memory cells selected simultaneously by a word line. Thereafter, the write circuit writes the data on a second page into the plurality of first memory cell. Then, the write circuit writes the data on the first and second pages into second memory cells adjoining 10 the first memory cells in the bit line direction.

A memory device includes a memory including memory cells, each of the memory cells being configured to store multiple bits of data. The memory device includes a controller configured to map the levels of the memory cells to bits such that a first half of the levels have a bit with a first binary value in a desired bit position and a second half of the levels have a bit with a second binary value in the desired bit position. The first half of the levels are a first group of consecutive levels, and the second half of the levels are a second group of consecutive levels. The controller is configured to generate a distribution for writing the data to the memory cells based on the mapping, and write the data to the memory cells based on the determined distribution.