A non-volatile memory device includes a memory cell array including memory cells, a page buffer circuit including page buffers respectively connected to bit lines, a buffer memory, and a control logic configured to control a read operation on the memory cells. In the read operation, the control logic obtains valley search detection information including read target block information and word line information by performing a valley search sensing operation on a distribution of threshold voltages of the memory cells, obtains a plurality of read levels using a read information model by inputting the valley search detection information into the read information model, and performs a main sensing operation for the read operation.

A nonvolatile memory device includes a peripheral circuit region and a memory cell region vertically connected with the peripheral circuit region, the peripheral circuit region including at least one first metal pad, and the memory cell region including at least one second metal pad directly connected with the at least one first metal pad. A method of programming the nonvolatile memory device incudes: receiving a programming command, data for a plurality of pages, and an address corresponding to a selected word-line; programming the data for one of the pages to an unselected word-line; reading data of a previously programmed page from the selected word-line; and programming the data for the remaining pages and the data of the previously programmed page to the selected word-line.

When programming and verifying a memory device which includes a plurality of memory cells and a plurality of word lines, a first coarse programming is first performed on a first memory cell among the plurality of memory cells which is controlled by a first word line among the plurality of word lines, and then a second coarse programming is performed on a second memory cell among the plurality of memory cells which is controlled by a second word line among the plurality of word lines. Next, a first coarse verify current is used for determining whether the first memory cell passes a coarse verification and a second coarse verify current is used for determining whether the second memory cell passes a second coarse verification, wherein the second coarse verify current is smaller than the first coarse verify current.

The present disclosure generally relates to improving programming to data storage devices, such as solid state drives (SSDs). A first memory device has a first XOR element and a second memory device has a second XOR element. The ratio of the first XOR element to the capacity of the first memory device is substantially smaller than the ratio of the second XOR element to the capacity of the second memory device. A read verify operation to find program failures is executed on either a wordline to wordline basis, an erase block to erase block basis, or both a wordline to wordline basis and an erase block to erase block basis. Because the program failures are found and fixed prior to programming to the second memory device, the second XOR element may be decreased substantially.

A first data stored at a first portion of a memory cell and a second data stored at a second portion of the memory cell are identified. A first error rate associated with first data stored at the first portion of the memory cell is determined. The first error rate is adjusted to exceed a second error rate associated with the second data stored at the second portion of the memory cell. A determination is made as to whether the first error rate exceeds a threshold. The second data stored at the second portion of the memory cell is provided for use in an error correction operation by a controller associated with the memory cell in response to determining that the first error rate exceeds the threshold.

A non-volatile semiconductor memory device includes an electrically data rewritable non-volatile semiconductor memory cell and a write circuit for writing data in the memory cell, the write circuit writing a data in the memory cells by supplying a write voltage Vpgm and a write control voltage VBL to the memory cell, continuing the writing of the data in the memory cell by changing the value of the write control voltage VBL in response to an advent of a first write state of the memory cell and inhibiting any operation of writing a data to the memory cell by further changing the value of the write control voltage VBL to Vdd in response to an advent of a second write state of the memory cell.

A non-volatile memory includes a cell array, a current supply circuit, a path selecting circuit and a verification circuit. The cell array includes plural multi-level memory cells in an m×n array. The cell array is connected with m word lines and n lines. Each of the plural multi-level memory cells is in one of X storage states. The current supply circuit provides plural reference currents. The path selecting circuit is connected with the current supply circuit and the n bit lines. The verification circuit is connected with the path selecting circuit, and generates n verification signals. A first path selector of the path selecting circuit is connected with a path selecting circuit and a first bit line. A first verification device of the verification circuit is connected with the first path selector and generates a first verification signal.

A memory device includes a memory array of memory cells and control logic, operatively coupled with the memory array. The control logic is to perform operations, which include causing the memory cells to be programmed with an initial voltage distribution representing multiple logical states; causing the memory cells to be programmed with a subsequent voltage distribution representing a subset of the multiple logical states at a higher voltage than that of the initial voltage distribution, wherein the subset of the multiple logical states is compacted above a program verify voltage level for the subsequent voltage distribution; and causing a first program verify operation of the subsequent voltage distribution to be performed on the memory cells to verify one or more voltage levels of the subsequent voltage distribution.

Upon detecting power loss during the process of programming multi-level cell (MLC) memory in a storage system, the storage system takes steps to prevent data loss. In one example, the controller sends a graceful shutdown command to the memory, in response to which the memory aborts the ongoing programming operation and stores data from data latches associated with unprogrammed memory cells in single-level cell (SLC) memory. The memory can also store data from programmed memory cells in the SLC memory. The data to be programmed in the MLC memory can be reconstructed prior to powering down the storage system or after the storage system is powered back up. The reconstructed data can then be programmed in the MLC memory.

A storage system receives a request to read data that is located in a wordline undergoing a program operation. Instead of waiting for the program operation to complete, which would increase read latency, the storage system aborts the program operation and reconstructs the data from successfully-programmed memory cells in the wordline and from data latches associated with unsuccessfully-programmed memory cells in the wordline. The reconstructed data is then sent to the host. The program abort command can be similar to one used to provide a graceful shutdown in a power-loss situation.