An apparatus has a controller and an array of memory cells, including a first section comprising a plurality of rows and a second section comprising a plurality of rows. The controller configured to, in association with wear leveling, transfer data stored in a first row of the first section from the first row to a register, transfer the data from the register to a destination row of the second section while data in a second row of the first section is being sensed.

Methods, systems, and devices related to data relocation via a cache are described. In one example, a memory device in accordance with the described techniques may include a memory array, a sense amplifier array, and a signal development cache configured to store signals (e.g., cache signals, signal states) associated with logic states (e.g., memory states) that may be stored at the memory array (e.g., according to various read or write operations). In some cases, the memory device may transfer data from a first address of the memory array to the signal development cache. The memory device may transfer the data stored in the signal development cache to a second address of the memory array based on a parameter associated with the first address of the memory array satisfying a criterion for performing data relocation.

Systems, methods, and apparatus to evaluate read margin when reading memory cells in a memory device. In one approach, a controller of a memory device applies an initial read voltage of an initial polarity to memory cells. Errors from the read are used to determine whether read retry is needed. If so, a pre-read voltage of an opposite polarity is applied, and errors determined. Based on the errors from applying the pre-read voltage, a polarity is selected for the read retry voltage. The read retry voltage of the selected polarity is then applied to the memory cells.

Methods, systems, and devices for spare substitution in a memory system are described. Aspects include a memory device identifying a rotation index that indicates a first assignment of logical channel to physical channels for code words stored in a memory medium. The memory device may use a pointer to indicate one or more code word addresses that are to be rotated and update a value of the pointer associated with a range for the rotation index based on a condition being satisfied. The memory device may rotate a first code word according to a first assignment of the rotation index, where the rotating may occur at an address of the memory medium corresponding to the updated value of the pointer. Additionally, the memory device may execute access operations on the memory medium that include multiplexing multiple logical channels to multiple physical channels based on the rotation index and the pointer.

Technology is described for selecting a group of reversible-resistance memory cells in which to store data based on information regarding switching the reversible-resistance memory cells from a first resistance state in which the reversible-resistance memory cells are in immediately after fabrication to a second resistance state for the first time after fabrication. Information regarding switching the reversible-resistance memory cells from the first resistance state to the second resistance state for the first time after fabrication may provide insight into factors including, but not limited to, endurance and data retention. In one aspect, a control circuit is configured to select a group of reversible-resistance memory cells in which to store data based on both the difficulty in switching from the first resistance state to the second resistance state for the first time after fabrication and a temperature of the data to be stored in the memory system.

A memory controller may be provided. The memory controller may include a wear-leveler may be configured to determine whether execution of a swapping operation is required based on reception of a write command for a stack region.

To perform refresh without saving data, and prevent corruption of data in non-volatile memories. A number-of-write-operations information holding unit holds number-of-write-operations information, which is the number of write operations of a non-volatile memory to which access is made in units of pages which are divided by a page size. A determination unit determines whether or not refresh, which is reversing of values of all memory cells constituting the pages, is necessary on the basis of the held number-of-write-operations information. A write control unit further performs the refresh in addition to writing when the refresh is necessary on the basis of a result of the determination at a time of the writing with respect to the pages.

Methods and systems for managing memory and stress to memory systems. A method for managing memory includes receiving from a software application memory retention requirements for application data. The memory retention requirements include storage duration length and/or criticality of data retention. The method also includes storing the application data in one of a plurality of memory regions in non-volatile memory based on the memory retention requirements and memory retention characteristics of the memory regions. Each memory region may have different memory retention characteristics.

A storage array programming method and device for a resistive random access memory (RAM) are proposed. The resistive RAM comprising a storage array, the storage array comprising a group of storage units to which data is to be written. The programming method comprises: reading the currently stored data in the group of storage units and comparing bit by bit the currently stored data with the data to be written to determine whether the currently stored data is consistent with the data to be written, and generating a data write state according to the determination result; determining the data write state, and by a set operation or a reset operation, writing the data to be written only to the storage units where the currently stored data is inconsistent with the data to be written; checking whether any storage unit having a write failure exists during the set operation or the reset operation; if so, then repeating the previous steps until the writing is completed. The programming method can avoid repetitive writing, thus not only reducing write interference with a unit to improve writing efficiency of the unit, but also reducing power consumption of writing.

A memory architecture comprises a first memory macro comprising a first plurality of memory cells, a second memory macro comprising a second plurality of memory cells, and a control logic coupled to the first and second memory macros. The control logic is configured to write a logical state to each of the first and second pluralities of memory cells by using first and second signal levels, respectively, thereby causing the first and second memory macros to be used in first and second applications, respectively, the first and second signal levels being different and the first and second applications being different. The first and second memory macros are formed on a single chip, and wherein the first and second pluralities of the memory cells comprise a variable resistance dielectric layer formed using a single process recipe.