An operating method is provided which includes receiving a read command and a read address, performing a read operation about memory cells selected according to the read address, and performing a reliability verification read operation about unselected memory cells adjacent to the selected memory cells. A number of memory cells each corresponding to at least one state of an erase state and program states of the unselected memory cells is counted as a count value based on the result of the reliability verification read operation. Data read through the read operation is output to an external device and data read through the reliability verification read operation is not output to the external device.

A memory device may include memory cells configured to establish multiple levels of charge distributions; and a memory controller configured to perform operations on the memory cells. The operations may include recording a bit count number for a highest level of charge distributions within a set of memory cells, recording a bit count number for a lowest level of charge distributions within the set of memory cells, counting bits for the highest level of charge distributions within the set of memory cells, counting bits in the lowest level of charge distributions within the set of memory cells, comparing the counted bits for the highest level to the recorded bit count number for the highest level, and comparing the counted bits for the lowest level to the recorded bit count number for the lowest level.

A memory system includes a memory device including a plurality of memory blocks, each block having a plurality of pages to store data; and a controller suitable for detecting a number of error bits from data stored in the plurality of pages; summing the number of error bits; generating a bad word line list based on the sum of the error bits; and performing a test read operation on the plurality of pages based on the bad word line list.

A memory system includes a nonvolatile memory configured to execute one of a plurality of read operations, including a first read operation and a second read operation, and a memory controller configured to issue a read command to the nonvolatile memory to cause the nonvolatile memory to execute one of the plurality of read operations. The memory controller is configured to receive a read request, estimate a reliability level of a result of a read operation to be executed by the nonvolatile memory to read data from a physical address specified in the read request, select one of the first and second read operations to be executed first in a read sequence corresponding to the read request by the nonvolatile memory based on the estimated reliability level, and instruct the nonvolatile memory to execute the selected read operation.

A memory array includes strings that are configured to store keywords and inverse keywords corresponding to keys according to content addressable memory (CAM) storages schemes. A read circuit performs a CAM read operation over a plurality of iterations to determine which of the keywords are matching keywords that match a target keyword. During the iterations, a read controller biases word lines according to a plurality of modified word line bias setting that are each modified from an initial word line bias setting corresponding to the target keyword. At the end of the CAM read operation, the read controller detects which of the keywords are matching keywords, even if the strings are storing the keywords or inverse keywords with up a certain number of bit errors.

Systems and methods are disclosed, comprising a memory device comprising multiple groups of memory cells, the groups comprising a first group of memory cells and a second group of memory cells configured to store information at a same bit capacity per memory cell, and a processing device operably coupled to the memory device, the processing device configured to adjust a scan event threshold for one of the first or second groups of memory cells to a threshold less than a target scan event threshold for the first and second groups of memory cells to distribute scan events in time on the memory device.

The present disclosure is directed to read sample offset most probable bit operation associated with a memory component. A processing device generates a first set of read data associated with a memory component, the first set of read data comprising a first sequence of bit values. The processing device generates a second set of read data associated with the memory component, the second set of read data comprising a second sequence of bit values. The processing device generates a third set of read data associated with the memory component, the third set of read data comprising a third sequence of bit values. A most probable bit operation is performed to compare the first sequence of bit values, the second sequence of bit values, and the third sequence of bit values to generate and store a most probable bit sequence.

Read disturb audit techniques that include algorithmically applying audit verify voltages to erased wordlines in an open memory block are described. In an audit verify technique, a pass-through voltage ensured to be higher than any threshold voltage of any cell is applied to each wordline in an open memory block that includes one or more programmed memory cells, and an audit verify voltage lower than the pass-through voltage is applied to each erased wordline. A first bit count representing a number of non-conductive bitline(s) is determined and compared to a threshold value to determine whether to continue or discontinue block operation. In an audit verify and audit gap technique, the erased wordlines are divided into disjoint first and second groups, and an audit verify voltage and a non-verify voltage are alternatively applied to the groups in different audit verify stages.

A three dimensional stacked nonvolatile semiconductor memory according to an example of the present invention includes a memory cell array comprised of first and second blocks. The first block has a first cell unit which includes a memory cell to be programmed and a second cell unit which does not include a memory cell to be programmed, and programming is executed by applying a program potential or a transfer potential to word lines in the first block after the initial potential of channels of the memory cells in the first and second cell units is set to a plus potential. In the programming, the program potential and the transfer potential are not applied to word lines in the second block.

A data storage device including, in one implementation, a non-volatile memory and a controller. The non-volatile memory includes a memory block. The memory block includes a plurality of word lines that are written sequentially from a first end of the memory block to a second end of the memory block. The controller is coupled to the non-volatile memory. The controller is configured to determine a last written word line of the memory block. The controller is also configured to set a non-selected word line voltage based on the last written word line of the memory block. The controller is further configured to apply the non-selected word line voltage to non-selected word lines of the memory block.