According to one embodiment, three bits stored in one memory cell of a nonvolatile memory correspond to three pages. In first page writing, a threshold voltage becomes within a first or second region base on a bit value. In second page writing, if being within the first region, it becomes within the first or fourth region; and if being within the second region, it becomes within the second or third region. In the third page writing, if being within the first region, it becomes within the first or sixth region; if being within the second region, it becomes within the second or seventh region; if being within the third region, it becomes within the third or eighth region; and if being within the fourth region, it becomes within the fourth or fifth region.

A nonvolatile memory device performs a compare and write operation. The compare and write operation includes reading read data from memory cells, inverting first write data to generate second write data, adding a first flag bit to the first write data to generate third write data and adding a second flag bit to the second write data to generate fourth write data, performing a reinforcement operation on each of the third write data and the fourth write data to generate fifth write data and sixth write data, and comparing the read data with each of the fifth write data and the sixth write data and writing one of the fifth and sixth write data in the memory cells based on a result of the comparison.

Devices and techniques for NAND temperature-aware operations are disclosed herein. A device controller can receive a command to write data to a component in the device. A temperature corresponding to the component can be obtained in response to receiving the command. The command can be executed by the controller to write data to the component. Executing the command can include writing the temperature into a management portion of the device that is separate from a user portion of the device to which the data is written.

A non-volatile memory has an array of non-volatile memory cells, first reference word lines and second reference word lines, and sense amplifiers. The sense amplifiers read system data, that has been written to supplemental non-volatile memory cells of the first reference word lines, using comparison of the supplemental non-volatile memory cells of the first reference word lines to supplemental non-volatile memory cells of the second reference word lines. Status of erasure of the non-volatile memory cells of the array is determined based on reading the system data.

A system includes a memory device and a processing device coupled to the memory device. The memory device can include memory cells. The processing device can store operation system data in the memory cells in a single level cell (SLC) mode. The processing device can assert a flag indicating that the data written to the memory cells in the SLC mode is to remain stored in the SLC mode. The processing device can de-assert the flag, thereby indicating that the data is foldable into memory cells in a non-SLC mode.

According to one embodiment, a semiconductor memory includes a first memory cell array including a plurality of first memory cells; and a second memory cell array including a plurality of second memory cells. Each of threshold voltages of the first memory cells and the second memory cells is set to any of a first threshold voltage, a second threshold voltage higher than the first threshold voltage, and a third threshold voltage higher than the second threshold voltage. Data of three or more bits including a first bit, a second bit, and a third bit is stored using a combination of a threshold voltage of the first memory cell and a threshold voltage of the second memory cell.

According to one embodiment, a memory system includes a semiconductor memory device including a memory cell capable of holding at least 4-bit data and a controller configured to control a first write operation and a second write operation based on the 4-bit data. The controller includes a conversion circuit configured to convert 4-bit data into 2-bit data. The semiconductor memory device includes a recovery controller configured to recover the 4-bit data based on the converted 2-bit data and data written in the memory cell by the first write operation. The first write operation is executed based on the 4-bit data received from the controller, and the second write operation is executed based on the 4-bit data recovered by the recovery controller.

A system includes a memory device and a processing device coupled to the memory device. The memory device can include memory cells. The processing device can store operation system data in the memory cells in a single level cell (SLC) mode. The processing device can assert a flag indicating that the data written to the memory cells in the SLC mode is to remain stored in the SLC mode. The processing device can de-assert the flag, thereby indicating that the data is foldable into memory cells in a non-SLC mode.

Systems, apparatuses, and methods provide for technology for distinguishing an erased state, a first pass programmed state, and a second pass programmed state of a memory page. A threshold voltage state verify sense is performed. A memory page status is determined based on the threshold voltage state verify sense. The memory page status is one of erased, programmed with first pass data, and programmed with second pass data based on the threshold voltage state verify sense. A program continuation is performed after a program interruption based on the memory page status.

A memory device including: a memory area having a first memory block and a second memory block; and a control logic configured to control the first memory block and the second memory block in a first mode and a second mode, wherein in the first mode only a control operation for the first memory block is executable, and in the second mode control operations for the first memory block and the second memory block are executable, wherein the control logic counts the number of accesses made to the second memory block in the first mode, and stores the number of accesses as scan data in the second memory block.