A memory system includes a non-volatile memory chip that includes a memory cell array, and a memory controller. The memory controller is configured to perform a read operation on the non-volatile memory chip by instructing the non-volatile memory chip to perform a sensing operation to read data stored in the memory cell array, estimating a time when the read data becomes ready to be transferred from the non-volatile memory chip to the memory controller, and instructing the non-volatile memory chip, after the estimated time, to perform a transfer operation to transfer the read data to the memory controller.

Methods, systems, and devices for distribution-following access operations for a memory device are described. In an example, the described techniques may include identifying an activation of a first memory cell at a first condition of a biasing operation, and identifying an activation of a second memory cell at a second condition of the biasing operation, and determining a parameter of an access operation based at least in part on a difference between the first condition and the second condition. In some examples, the memory cells may be associated with a configurable material element, such as a chalcogenide material, that stores a logic state based on a material property of the material element. In some examples, the described techniques may at least partially compensate for a change in memory material properties due to aging or other degradation or changes over time.

Methods, systems, and devices for programming techniques for polarity-based memory cells are described. A memory device may use a first type of write operation to program one or more memory cells to a first state and a second type of write operation to program one or more memory cells to a second state. Additionally or alternatively, a memory device may first attempt to use the first type of write operation to program one or more memory cells, and then may use the second type of write operation if the first attempt is unsuccessful.

According to one embodiment, a memory device includes a memory cell including a resistance change memory element in which a plurality of data values according to resistance are allowed to be set, and a selector element connected to the resistance change memory element in series, a word line supplying a select signal for selecting the resistance change memory element by the selector element to the memory cell, a bit line to which a data signal according to a data value set in the resistance change memory element is read, a load circuit connected to the memory cell in series and functioning as a load, and a comparator circuit which compares a voltage obtained by the load circuit with a plurality of reference voltages.

A memory device includes a plurality of memory cells, each including a switching device and an information storage device connected to the switching device and having a phase change material, the plurality of memory cells connected to a plurality of word lines and a plurality of bit lines, a decoder circuit determining at least one of the plurality of memory cells to be a selected memory cell, and a program circuit configured to input a programming current to the selected memory cell to perform a programming operation and configured to detect a resistance of the selected memory cell to adjust a magnitude of the programming current.

An embodiment in the application may include an analog memory structure, and methods of writing to such a structure, including a volatile memory element in series with a non-volatile memory element. The analog memory structure may change resistance upon application of a voltage. This may enable accelerated writing of the analog memory structure.

Memory devices have an array of elements in two or more dimensions. The memory devices use multiple access lines arranged in a grid to access the memory devices. Memory cells are located at intersections of the access lines in the grid. Drivers are used for each access line and configured to transmit a corresponding signal to respective memory cells of the plurality of memory cells via a corresponding access line. The memory devices also include compensation circuitry configured to determine which driving access lines driving a target memory cell of the plurality of memory cells has the most distance between the target memory cell and a respective driver. The plurality of access lines comprise the driving access lines. The compensation circuitry also is configured to output compensation values to adjust the voltages of the driving access lines based on a polarity of the voltage of the longer driving access line.

The present invention is directed to a nonvolatile memory device including a plurality of memory cells arranged in rows and columns, a plurality of word lines with each connected to a respective row of the memory cells along a row direction, a plurality of bit lines with each connected to a respective column of the memory cells along a column direction; a column decoder connected to the bit lines; a plurality of sense amplifiers connected to the column decoder; and a plurality of sense amplifier control circuits. Each of the sense amplifiers is connected to a unique one of the sense amplifier control circuits. Each of the sense amplifier control circuits includes a current detector circuit for detecting a sensing current, a current booster circuit for boosting the sensing current, and a timer circuit for providing a delayed trigger for a respective one of the sense amplifiers connected thereto.

Disclosed herein is a memory cell including a memory element and a selector device. Data may be stored in both the memory element and selector device. The memory cell may be programmed by applying write pulses having different polarities and magnitudes. Different polarities of the write pulses may program different logic states into the selector device. Different magnitudes of the write pulses may program different logic states into the memory element. The memory cell may be read by read pulses all having the same polarity. The logic state of the memory cell may be detected by observing different threshold voltages when the read pulses are applied. The different threshold voltages may be responsive to the different polarities and magnitudes of the write pulses.

An apparatus for performing in-memory processing includes a memory cell array of memory cells configured to output a current sum of a column current flowing in respective column lines of the memory cell array based on an input signal applied to row lines of the memory cells, a sampling circuit, comprising a capacitor connected to each of the column lines, configured to be charged by a sampling voltage of a corresponding current sum of the column lines, and a processing circuit configured to compare a reference voltage and a currently charged voltage in the capacitor in response to a trigger pulse generated at a timing corresponding to a quantization level, among quantization levels, time-sectioned based on a charge time of the capacitor, and determine the quantization level corresponding to the sampling voltage by performing time-digital conversion when the currently charged voltage reaches the reference voltage.