Systems, methods and apparatus to read target memory cells having an associated reference memory cell configured to be representative of drift or changes in the threshold voltages of the target memory cells. The reference cell is programmed to a predetermined threshold level when the target cells are programmed to store data. In response to a command to read the target memory cells, estimation of a drift of the threshold voltage of the reference is performed in parallel with applying an initial voltage pulse to read the target cells. Based on a result of the drift estimation, voltage pulses used to read the target cells can be modified and/or added to account for the drift estimated using the reference cell.

Systems, apparatuses and methods may provide for technology that determines a power-off period associated with a non-volatile memory (NVM), sets a completion time of a write procedure corresponding to the NVM to a first value if the power-off period exceeds a threshold, and sets the completion time to a second value if the power-off period does not exceed the threshold, wherein the first value is greater than the second value.

A storage circuit (11) includes memory cells (MCij), each of which includes an MTJ element, and reference cells (RCi), each of which includes a series circuit of an MTJ element set to a low-resistance state and a linear resistor (FR). A RW circuit (23j) that includes a sense amplifier is provided in each column of a memory cell array (21), and compares a data voltage on a corresponding bit line (BLj) with a reference voltage. The sense amplifier includes a pair of PMOS transistors to which the data voltage and the reference voltage are applied, a CMOS sense latch that is connected to a current path of the PMOS transistors.

A memory device and a programming method of the memory device are provided. The memory device includes a bottom electrode, a heater, a phase change layer and a top electrode. The heater is disposed on the bottom electrode, and includes heat conducting materials different from one another in terms of electrical resistivity. A first one of the heat conducting materials has a periphery wall portion and a bottom plate portion connected to and surrounded by the periphery wall portion. A second one of the heat conducting materials is disposed on the bottom plate portion of the first one of the heat conducting materials, and laterally surrounded by the periphery wall portion of the first one of the heat conducting materials. The phase change layer is disposed on the heater and in contact with the heat conducting materials. The top electrode is disposed on the phase change layer.

Methods, systems, and devices for operating a memory array are described. A memory controller may be configured to provide enhanced bandwidth on a command/address (C/A) bus, which may have a relatively low pin count, through use of a next partition command that may repeat an array command from a current partition at a different partition indicated by the next partition command. Such a next partition command may use fewer clock cycles than a command that includes a complete instruction and memory location information.

According to an embodiment, a reinforcement learning system includes a memristor array in which each of a plurality of first direction lines corresponds to one of a plurality of states, and each of a plurality of second direction lines corresponds to one of a plurality of actions, a first voltage application unit that individually applies voltage to the first direction lines, a second voltage application unit that individually applies voltage to the second direction lines, a action decision circuit that decides action to be selected by an agent in a state corresponding to a first direction line to which a readout voltage is applied, a action storage unit that stores action selected by the agent in each state that can be caused in an environment, and a trace storage unit that stores a time at which the state is caused by action selected by the agent.

An integrated circuit memory device, having: a first wire; a second wire; a memory cell connected between the first wire and the second wire; a first voltage driver connected to the first wire; and a second voltage driver connected to the second wire. During an operation to read the memory cell, the second voltage driver is configured to start ramping up a voltage applied on the second wire after the first voltage driver starts ramping up and holding a voltage applied on the first wire.

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.

A memory unit with a multiply-accumulate assist scheme for a plurality of multi-bit convolutional neural network based computing-in-memory applications is controlled by a reference voltage, a word line and a multi-bit input voltage. The memory unit includes a non-volatile memory cell, a voltage divider and a voltage keeper. The non-volatile memory cell is controlled by the word line and stores a weight. The voltage divider includes a data line and generates a charge current on the data line according to the reference voltage, and a voltage level of the data line is generated by the non-volatile memory cell and the charge current. The voltage keeper generates an output current on an output node according to the multi-bit input voltage and the voltage level of the data line, and the output current is corresponding to the multi-bit input voltage multiplied by the weight.

Various implementations are related to an apparatus with memory cells arranged in columns and rows, and the memory cells are accessible with a column control voltage for accessing the memory cells via the columns and a row control voltage for accessing the memory cells via the rows. The apparatus may include neural network circuitry having neuronal junctions that are configured to receive, record, and provide information related to incoming voltage spikes associated with input signals based on resistance through the neuronal junctions. The apparatus may include stochastic re-programmer circuitry that receives the incoming voltage spikes, receives the information provided by the neuronal junctions, and reconfigure the information recorded in the neuronal junctions based on the incoming voltage spikes associated with the input signals along with a programming control signal provided by the memory circuitry.