An example apparatus includes a memory comprising a plurality of managed units corresponding to respective groups of resistance variable memory cells and a controller coupled to the memory. The controller is configured to cause performance of a cleaning operation on a selected group of the memory cells and generation of error correction code (ECC) parity data. The controller may be further configured to cause performance of a write operation on the selected group of cells to write an inverted state of at least one data value to the selected group of cells and write an inverted state of at least one of the ECC parity data to the selected group of cells.

A method includes determining a first memory access count threshold for a first word line of a block of memory cells and determining a second memory access count threshold for a second word line of the block of memory cells. The second memory access count threshold can be greater than the first memory access count threshold. The method can further include incrementing a memory block access count corresponding to the block of memory cells that includes the first word line and the second word line in response to receiving a memory access command and refreshing the first word line when the memory block access count corresponding to the block of memory cells is equal to the first memory access count threshold.

A variable resistive memory device includes a memory cell, a first circuit, and a second circuit. The memory cell is connected between a word line and a bit line. The first circuit provides the bit line with a first pulse voltage based on at least one enable signal. The second circuit provides the word line with a second pulse voltage based on the enable signal. The first circuit generates the first pulse voltage increased in steps from an initial voltage level to a target voltage level.

Methods, systems, and devices for parallel drift cancellation are described. In some instances, during a first duration, a first voltage may be applied to a word line to threshold one or more memory cells included in a first subset of memory cells. During a second duration, a second voltage may be applied to the word line to write a first logic state to one or more memory cells included in the first subset and to threshold one or more memory cells included in a second subset of memory cells. During a third duration, a third voltage may be applied to the word line to write a second logic state to one or more memory cells included in the second subset of memory cells.

Methods, systems, and devices for parallel drift cancellation are described. In some instances, during a first duration, a first voltage may be applied to a word line to threshold one or more memory cells included in a first subset of memory cells. During a second duration, a second voltage may be applied to the word line to write a first logic state to one or more memory cells included in the first subset and to threshold one or more memory cells included in a second subset of memory cells. During a third duration, a third voltage may be applied to the word line to write a second logic state to one or more memory cells included in the second subset of memory cells.

A memory circuit includes a first driver circuit, a first column of memory cells coupled to the first driver circuit, a first current source, a tracking circuit configured to track a leakage current of the first column of memory cells, and a footer circuit coupled to the first column of memory cells, the first current source and the tracking circuit.

A memory device and a method of operating the same. The memory device includes a memory cell array including a plurality of memory cells disposed in an area where a plurality of word lines and a plurality of bit lines cross each other; a row decoder including row switches and configured to perform a selection operation on the plurality of word lines; a column decoder including column switches and configured to perform a selection operation on the plurality of bit lines; and a control logic configured to control, in a data read operation, a precharge operation to be performed on a selected word line in a word line precharge period, and to control a precharge operation to be performed on a selected bit line in a bit line precharge period; wherein a row switch connected to the selected word line is weakly turned on in the bit line precharge period.

An apparatus for reading a bit of a memory array includes a bit cell column, voltage enhancement circuitry, and control circuitry. The voltage enhancement circuitry is configured to couple a bitline to a reference node. The control circuitry is configured to, in response to a read request for a bitcell element of a plurality of bitcell elements, couple a current source to the bitcell column such that a read current from the current source flows from the source line, through the bitcell column and the voltage enhancement circuitry, to the reference node and determine a state for the bitcell element based on a voltage between the source line and the reference node. The voltage enhancement circuitry is configured to generate, when the read current flows through the voltage enhancement circuitry, a voltage at the bitline that is greater than a voltage at the reference node.

Methods, systems, and devices for dirty write on power off are described. In an example, the described techniques may include writing memory cells of a device according to one or more parameters (e.g., reset current amplitude), where each memory cell is associated with a storage element storing a value based on a material property associated with the storage element. Additionally, the described techniques may include identifying, after writing the memory cells, an indication of power down for the device and refreshing, before the power down of the device, a portion of the memory cells based on identifying the indication of the power down for the device. In some cases, refreshing includes modifying at least one of the one or more parameters for a write operation for the portion of the memory cells.

A data storage device may include a storage including a plurality of storage regions each composed of a plurality of pages; and a controller. The controller is configured to select a plurality of target open regions from open regions among the storage regions on the basis of health information of the open regions, in each of which a programmed page and an unprogrammed page coexist, and perform control so that refresh operations for the respective target open regions are performed in a time-distributed manner.