Memory sense amplifiers and memory verification methods are described. According to one aspect, a memory sense amplifier includes a first input coupled with a memory element of a memory cell, wherein the memory element has different memory states at different moments in time, a second input configured to receive a reference signal, modification circuitry configured to provide a data signal at the first input from the memory element having a plurality of different voltages corresponding to respective ones of different memory states of the memory cell at the different moments in time, and comparison circuitry coupled with the modification circuitry and configured to compare the data signal and the reference signal at the different moments in time and to provide an output signal indicative of the memory state of the memory cell at the different moments in time as a result of the comparison to implement a plurality of verify operations of the memory states of the memory cell at the different moments in time.

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.

Apparatuses, methods, and systems for sensing two memory cells to determine one data value are described herein. An embodiment includes a memory having a plurality of memory cells and circuitry configured to sense memory states of each of two memory cells to determine one data value. One data value is determined by sensing the memory state of a first one of the two memory cells using a first sensing voltage in a sense window between a first threshold voltage distribution corresponding to a first memory state and a second threshold voltage distribution corresponding to a second memory state and sensing the memory state of a second one of the two memory cells using a second sensing voltage in the sense window. The first and second sensing voltages are selectably closer in the sense window to the first threshold voltage distribution or the second threshold voltage distribution.

Mechanisms or techniques for improving operations such as program or erase operations that are intended to set a state of one or more multi-level memory cells (MLC) to a selected or designated state. For example, a first voltage pulse can be applied to an MLC that is intended to set the MLC to a desired state. Thereafter, a sensing pulse can be applied to the MLC, and one or more suitable electrical characteristic (EC) such as resistance can be measured and reported. This measured EC can then be compared to thresholds that define the range of acceptable values for the EC in order for the MLC to be deemed to be in the selected state. If the measured EC is not within the suitable range threshold, then one or more additional voltage pulses can be applied in order to properly set the MLC to the designated state and these additional voltages pulses can have different characteristics than the first voltage pulse.

The write reliability of a nonvolatile memory is improved by performing accurate verification of write data. In a memory controller of an information processing system, a determination unit determines whether a state of a memory cell after writing data is stable in a nonvolatile memory including the memory cell having an unstable state period after writing data. A verification unit performs verification by comparing read data which is read from the memory cell where the data is written on the basis of a result of the determination, with write data involved in the writing. A write control unit performs writing of the data and rewriting of the write data based on a result of the verification.

Technology for verifying cell programming for a phase change memory array is disclosed. In an example, a method may include sending a reset pulse to a phase change memory cell. The method may further include sensing a threshold voltage of the phase change memory cell in response to applying first and second verify voltages across the phase change memory cell, where the second verify voltage is lower than the first verify voltage. The method may also include determining whether the threshold voltage of the phase change memory cell was below the first or second verify voltages.

Disclosed is an operating method of an electronic device, which includes receiving input data, selecting a program voltage pattern corresponding to the input data from among a plurality of program voltage patterns for storing the input data in a memristor array circuit, and storing the input data in the memristor array circuit depending on the program voltage pattern thus selected. Each of the plurality of program voltage patterns includes a plurality of voltage pulses in which a pulse magnitude gradually increases over time.

Nonvolatile memory (e.g. phase change memory) devices, systems, and methods of programming the nonvolatile memory including dual demarcation voltage sensing before writes.

The semiconductor memory includes a plurality of word lines; and a plurality of columns including a plurality of resistive storage cells corresponding to the plurality of word lines, the plurality of columns being divided into a plurality of pages each having one or more columns; a memory circuit coupled to the semiconductor memory to sense data stored in the resistive storage cells; and a memory control circuit coupled to the semiconductor memory and the memory circuit to control sensing of the stored data by the memory circuit to, in a read operation, sense data of resistive storage cells included in a selected page by continuously active-precharging one or more word lines among the plurality of word lines in a period in which the selected page among the plurality of pages is activated.

In an example, a method may include comparing input data to stored data stored in a memory cell and determining whether the input data matches the stored data based on whether the memory cell snaps back in response to an applied voltage differential across the memory cell.