A non-volatile memory system comprises a memory structure and a control circuit connected to the memory structure. The memory structure includes one or more planes of non-volatile memory cells. Each plane is divided into a plurality of partial planes. The control circuit is configured to write to and read from the memory cells by writing a partial page into a particular partial plane and reading the partial page from the particular partial plane using a set of parameters optimized for the particular partial plane.

A memory system includes a memory controller; and a memory device including a memory cell array, which includes a plurality of bit lines and a plurality of blocks. Each block includes a plurality of word lines, and each word line includes a plurality of phase-change random access memory (PRAM) cells connected, respectively, to the plurality of bit lines. The memory controller is configured to buffer write requests each including write data and is configured to perform a write operation that includes a reset phase and a subsequent set phase. The reset phase includes erasing the PRAM cells included in first word lines from among the plurality of word lines included in a selected block, from among the plurality of blocks, and the set phase includes, after the reset phase, writing the write data from the buffered write requests to the PRAM cells of the first word lines.

Memory devices and memory operational methods are described. One example memory system includes a common conductor and a plurality of memory cells coupled with the common conductor. The memory system additionally includes access circuitry configured to provide different ones of the memory cells into one of a plurality of different memory states at a plurality of different moments in time between first and second moments in time. The access circuitry is further configured to maintain the common conductor at a voltage potential, which corresponds to the one memory state, between the first and second moments in time to provide the memory cells into the one memory state.

An apparatus can have a memory comprising an array of resistance variable memory cells and a controller. The controller can be configured to receive to a dedicated command to write all cells in a number of groups of the resistance variable memory cells to a first state without transferring any host data corresponding to the first state to the number of groups. The controller can be configured to, in response to the dedicated command, perform a read operation on each respective group to determine states of the cells in each respective group, determine from the read operation any cells in each respective group programmed to a second state, and write only the cells determined to be in the second state to the first state.

An apparatus can have a memory comprising an array of resistance variable memory cells and a controller. The controller can be configured to receive to a dedicated command to write all cells in a number of groups of the resistance variable memory cells to a first state without transferring any host data corresponding to the first state to the number of groups. The controller can be configured to, in response to the dedicated command, perform a read operation on each respective group to determine states of the cells in each respective group, determine from the read operation any cells in each respective group programmed to a second state, and write only the cells determined to be in the second state to the first state.

In a method of writing data in a nonvolatile memory device including a plurality of cell strings, each of the plurality of cell strings includes a plurality of memory cells disposed in a vertical direction. A program target page is divided into a plurality of subpages. The program target page is connected to one of a plurality of wordlines. Each of the plurality of subpages includes memory cells that are physically spaced apart from one another. A program operation is sequentially performed on the plurality of subpages. A program verification operation is performed on the program target page including the plurality of subpages at a time.

A method for programming a resistive random access memory including a matrix of memory cells. This method includes a programming procedure that includes applying a programming voltage ramp to the memory cells of a part at least of the matrix, the programming voltage ramp starting at a first non-zero voltage value, called start voltage, and ending at a second voltage value, called stop voltage, greater in absolute value than the first voltage value. The stop voltage is determined such that each memory cell of said at least one part of the matrix has a first probability between 1/(10N) and 1/N of having a programming voltage greater in absolute value than the stop voltage (V.sub.stop), N being the number of memory cells in the at least one part of the matrix.

Memory devices and memory operational methods are described. One example memory system includes a common conductor and a plurality of memory cells coupled with the common conductor. The memory system additionally includes access circuitry configured to provide different ones of the memory cells into one of a plurality of different memory states at a plurality of different moments in time between first and second moments in time. The access circuitry is further configured to maintain the common conductor at a voltage potential, which corresponds to the one memory state, between the first and second moments in time to provide the memory cells into the one memory state.

Memory devices and memory operational methods are described. One example memory system includes a common conductor and a plurality of memory cells coupled with the common conductor. The memory system additionally includes access circuitry configured to provide different ones of the memory cells into one of a plurality of different memory states at a plurality of different moments in time between first and second moments in time. The access circuitry is further configured to maintain the common conductor at a voltage potential, which corresponds to the one memory state, between the first and second moments in time to provide the memory cells into the one memory state.

A non-volatile memory system comprises a memory structure and a control circuit connected to the memory structure. The memory structure includes one or more planes of non-volatile memory cells. Each plane is divided into a plurality of partial planes. The control circuit is configured to write to and read from the memory cells by writing a partial page into a particular partial plane and reading the partial page from the particular partial plane using a set of parameters optimized for the particular partial plane.