Abstract: The present disclosure relates to a method for accessing an array of memory cells, comprising the steps of storing user data in a plurality of memory cells of a memory array, storing, in a counter associated to the array of memory cells, count data corresponding to a number of bits in the user data having a predetermined first logic value, applying a read voltage to the memory cells to read the user data stored in the array of memory cells, applying the read voltage to the cells of the counter to read the count data stored in the counter and to provide a target value corresponding to the number of bits in the user data having the first logic value, wherein, during the application of the read voltage, the count data are read simultaneously to the user data in such a way that the target value is provided during the reading of the user data, and based on the target value of the counter, stopping the application of the read voltage when the number of bits in the user data having the first logic value corresponds

Abstract: The present disclosure describes a memory device comprising memory cells at cross points of access lines of a memory array, and a two-transistor driver comprising a P-type transistor and a N-type transistor connected to the P-type transistor, the two-transistor driver being configured to drive an access line of the memory array to a discharging voltage during an IDLE phase, to drive said access line to a floating voltage during an ACTIVE phase, and to drive said access line at least to a first or second read/program voltage during a PULSE phase.

Abstract: Systems, methods, and apparatus for a memory device. In one approach, known reference patterns are stored in a memory array. The patterns are associated with codewords stored in the memory array. A first pattern has all memory cells written to a first logic state (e.g., all logic ones), and a second pattern has all memory cells written to an opposite second logic state (e.g., all logic zeros). When a controller reads a codeword, the controller first reads memory cells of the associated reference patterns to determine data for estimating a threshold voltage distribution of memory cells in the codeword. Based on a number of memory cells of the reference patterns that snap when reading the first and second patterns, the controller selects a read voltage for reading the associated codeword.

Abstract: Methods, systems, devices, and techniques for read operations are described. In some examples, a memory device may include a first transistor (e.g., memory node transistor) configured to receive a precharge voltage at a first gate and output first voltage based on a threshold of the first transistor to a reference node via a first switch. The device may include a second transistor (e.g., a reference node transistor) configured to receive a precharge voltage and output a second voltage based on a threshold of the second transistor to a memory node via a second switch. The first voltage may be modified by a reference voltage and input to the second transistor. The second voltage may be modified by a voltage stored on a memory cell and input to the first transistor. The first and second transistor may output third and fourth voltages to be sampled to a latch.

Abstract: Methods, systems, and devices for a read algorithm for a memory device are described. When performing a read operation, the memory device may access a memory cell to retrieve a value stored by the memory cell. The memory device may compare a set of reference voltages with a signal output by the memory cell based on accessing the memory cell. Thus, the memory device may determine a set of candidate values stored by the memory cell, where each candidate value is associated with one of the reference voltages. The memory device may determine and output the value stored by the memory cell based on determining the set of candidate values. In some cases, the memory device may determine the value stored by the memory cell based on performing an error control operation on each of the set of candidate values to detect a quantity of errors within each candidate value.

Abstract: Methods and systems include memory devices with a memory array comprising a plurality of memory cells. The memory devices include a control circuit operatively coupled to the memory array and configured to receive a read request for data and to apply a plurality of read voltages to the memory array based on the read request. The control circuit is further configured to perform a data analysis for a first set of data read based on the application of the plurality of read voltages and to derive a demarcation bias voltage (VDM) based on the data analysis. The control circuit is also configured to apply the VDM to the memory array to read a second set of data.

Abstract: A system includes a memory array having pattern cells and data cells. The pattern cells are configured to store only a first logic state. The data cells are configured to store the first logic state or a second logic state. Bias circuitry is configured to apply voltages to the pattern cells and data cells. Sensing circuitry is configured to read the pattern cells. A controller is configured to apply, using the bias circuitry, first voltages to the pattern cells; determine, using the sensing circuitry, that at least a portion of the pattern cells switch; determine, based on the portion of the pattern cells that switch, to refresh a codeword; and apply, using the bias circuitry, the refresh of the codeword.

Abstract: Methods, systems, and devices related to counter-based sense amplifier method for memory cells are described. The counter-based read algorithm may comprise the following phases: storing in a counter associated to an array of memory cells the value of the number of bits having a predetermined logic value of the data bits stored in the memory array; reading from said counter the value corresponding to the number of bits having the predetermined logic value; reading the data stored in the array of memory cells by applying a ramp of biasing voltages; counting the number of bits having the predetermined logic value during the data reading phase; stopping the data reading phase when the number of bits having the predetermined logic value is equal to the value stored in said counter.

Abstract: Systems, methods, and apparatus for a memory device that uses multiple groups of pattern cells to select a voltage for reading memory cells. In one approach, a controller applies different magnitude levels of voltages to each of the groups of pattern cells. The controller determines which of the groups have pattern cells that first switch (e.g., switch at the lowest magnitude of applied voltage). Based on identifying the first group to switch, the controller selects a read voltage. The selected read voltage is used to read data cells (e.g., corresponding to a codeword).

Abstract: Systems, methods, and apparatus related to memory devices (e.g., storage class memory). In one approach, a memory device has a memory array including memory cells arranged as differential memory cell pairs, with each pair storing a single logical bit. The memory device has a controller that receives a command from a host to initiate a read operation. The memory cell pair is selected using bitlines and a common wordline. A partition of the memory array is accessed to read the data stored by the memory cell pair, and then store the read data in a latch for sending to the host. In response to accessing the partition, a counter is incremented. The controller statistically determines whether to perform a refresh operation for the partition based on comparing the current value of the counter to a value previously generated by a random number generator.

Abstract: Methods, systems, and devices for transistor configurations for vertical memory arrays are described. A memory device may implement a multi-transistor architecture, such as a two-transistor architecture, that is operable to couple pillars with bit lines. For example, a memory device may include a conductive pillar that extends through levels of a memory array. The pillar may be coupled with a first bit line via a first transistor and coupled with a second bit line via a second transistor. To access a memory cell coupled with the pillar, the memory device may bias a word line coupled with the memory cell to a first access voltage, bias one of the bit lines to a second access voltage, activate one of the transistors to couple the pillar with the one of the bit lines, and deactivate the other transistor to isolate the pillar from the other of the bit lines.

Abstract: Methods, systems, and devices for memory array seasoning are described. Some memory cells may have an undesirably high threshold voltage and thus a seasoning operation may be performed on a target memory cell. To season the target memory cell, a bit line and a word line associated with the cell may be activated. Additionally or alternatively, a word line coupled with a second memory cell (e.g., a helper memory cell) that shares the activated bit line may be activated. Accordingly, current flowing across the target memory cell may be increased, which may reduce its threshold voltage.

Abstract: Techniques are described for maintaining a stable voltage difference in a memory device, for example, during a critical operation (e.g., a sense operation). The voltage difference to be maintained may be a read voltage across a memory cell or a difference associated with a reference voltage, among other examples. A component (e.g., a local capacitor) may be coupled, before the operation, with a node biased to a first voltage (e.g., a global reference voltage) to sample a voltage difference between the first voltage and a second voltage while the circuitry is relatively quiet (e.g., not noisy). The component may be decoupled from the node before the operation such that a node of the component (e.g., a capacitor) may be allowed to float during the operation. The voltage difference across the component may remain stable during variations in the second voltage and may provide a stable voltage difference during the operation.

Abstract: A variety of applications can include one or more memory devices having one or more memory arrays of memory cells, where each memory cell is a resistive memory cell arranged such that a clamp current for the memory cell can be provided by an access line biasing circuit to the memory cell opposite a coupling of a sense circuit to a digit line to the memory array. The access line biasing circuit and the sense circuit can be operated in a digit line precharge phase and an access line biasing phase of a memory cell of the memory array using a set of switches to control activities for the memory cell in the memory array, the sense circuit, and the access line biasing circuit. A reference current can be provided from the access line biasing circuit to the sense circuit. Additional devices, systems, and methods are discussed.

Abstract: Methods, systems, and devices for memory array with multiplexed select lines are described. In some cases, a memory cell of the memory device may include a storage component, a first transistor coupled with a word line, and a second transistor coupled with a selection line to selectively couple the memory cell with a digit line. The selection line may be provided in parallel to each digit line for multiplexing the digit lines toward a sense amplifier while a plurality of drivers, one for each selection line, may be provided in a staggered configuration under the memory array and split in even drivers and odd drivers for corresponding adjacent tiles of the memory array.

Abstract: The present invention relates to a method of operating memory cells, comprising reading a previous user data from the memory cells; writing a new user data and merging the new user data with the previous user data into write registers; generating mask register information, and wherein the mask register information indicates bits of the previous user data stored in the memory cells to be switched or not to be switched in their logic values; counting numbers of a first logic value and a second logic value to be written using the mask register information, respectively; storing the numbers of the first logic value and the second logic value into a first counter and a second counter, respectively; and applying a programming pulse to the memory cells according to the mask register information.

Abstract: Methods, systems, and devices for shared decoder architecture for three-dimensional memory arrays are described. A memory device may include pillars coupled to an access line using two transistors positioned between the pillar and the access line. The gates of the two transistors may be coupled with respective gate lines coupled with circuitry configured to bias the gate line as part of an access operation for a memory cell coupled with the pillar. In some cases, the circuitry may be positioned between tiles of the memory device, at an end of one or more tiles of the memory device, between word line combs of a tile of the memory device, or a combination thereof.

Abstract: Methods, systems, and devices for multiple transistor architecture for three-dimensional memory arrays are described. A memory device may include conductive pillars coupled with an access line using two transistors positioned between the conductive pillar and the access line. As part of an access operation for a memory cell coupled with the conductive pillar, the memory device may be configured to bias the access line to a first voltage and activate the two transistors using a second voltage to couple the conductive pillar with the access line. Additionally, the memory device may be configured to bias a gate of a first transistor and a gate of a second transistor coupling an unselected conductive pillar with the access line to a third and fourth voltage, respectively, which may deactivate at least one of the first or second transistor during the access operation and isolate the unselected conductive pillar from the access line.

Abstract: Methods, systems, and devices for differential sensing for a memory device are described. A memory device in accordance with examples as disclosed herein may include a sense component having a signal development component for generating a sense signal, a reference component for generating a reference signal, and a tail component coupled with the signal development component and the reference component. The tail component may be configured for canceling common aspects of the sense signal and the reference signal. Additionally or alternatively, a memory device in accordance with examples as disclosed herein may include a sense component having a sense amplifier configured to operate in multiple power domains, with one power domain associated with sense signal and reference signal generation and comparison, and another power domain associated with logical signal or information transfer.

Abstract: Methods and apparatuses with counter-based reading are described. A memory cells of a codeword are accessed and respective voltages are generated. A reference voltage is generated and a logic state of each memory cell is determined based on the reference voltage and the respective generated cell voltage. The reference voltage is modified until a count of memory cells determined to be in a predefined logic state with respect to the last modified reference voltage value meets a criterium. In some embodiments the criterium may be an exact match between the memory cells count and an expected number of memory cells in the predefined logic state. In other embodiments, an error correction (ECC) algorithm may be applied while the difference between the count of cells in the predefined logic state and the expected number of cells in that state does not exceed a detection or correction power of the ECC.