Micron Technology Incorporated

Stmicroelectronics S.r.l.

Other

Politecnico Di Milano

Micro Technology, Inc.

Marco Sforzin

Paolo Amato

Daniele Balluchi

Graziano Mirichigni

Emanuele Confalonieri

Alessandro Orlando

Danilo Caraccio

Innocenzo Tortorelli

Umberto Di Vincenzo

Federico Pio

Nicola Del Gatto

Christophe Laurent

Marco Dallabora

Christophe Vincent Antoine Laurent

Marco Pietro Ferrari

Luca Barletta

Antonino Favano

Corrado Villa

Carla Giuseppina Poidomani

Paolo Fantini

Riccardo Muzzetto

Stephen S Pawlowski

Lorenzo Bedarida

Andrea Martinelli

Mattia Robustelli

Marco Massimo Ferrari

Carlo Lisi

Mario Allegra

Joseph M McCrate

Federica Cresci

Alessandro Tomasoni

Sandro Bellini

Antonino Geraci

John David Porter

Angelo Visconti

Giorgio Servalli

Nevil N Gajera

Yang Lu

Dionisio Minopoli

Lingming Yang

Niccolò Izzo

Marco Ferrario

Massimiliano Mollichelli

Antonio Geraci

Massimiliano Scotti

Nicola Rosito

A memory access method with improved bandwidth efficiency for reliability, availability, and serviceability (RAS) is described. The memory access method includes, in response to a memory access request, obtaining, using a first access granularity, a sub-stripe from a stripe of data stored on a plurality of memory media components arranged in a redundant array of independent data (RAID), and detecting an error in the sub-stripe of the data. The method further includes, in response to the detecting the error, obtaining, using a second access granularity, the stripe of the data from the plurality of memory media components, wherein the second access granularity is larger than the first access granularity. Corresponding devices are also described.

Low cost high performance LRAID

In a locked RAID memory system, the present method generates variable-length compressed data in a RAID stripe, which is stored along with the inclusion of a single RAID parity segment (parity strip) for the entire stripe. If any one data segment (data strip) in the RAID stripe should fail, as determined by a CRC check, the data can be recovered by XORing the single RAID parity segment with all the non-errored data segments in the stripe. However, in order to determine which data segment has failed, successive data segments must be XORed, and the CRC check reperformed, until the CRC error stands corrected. In an embodiment, the successive data segments may be tested in parallel with suitable hardware. In an embodiment, the successive data segments may be tested sequentially, or semi-in-parallel and semi-sequentially.

Variable-length locked-raid for CXL devices with compression

Methods, systems, and devices for address scrambling by linear maps in Galois fields are described. For instance, a device may determine a bijective matrix based on a power up condition. In some examples, the device may determine the bijective matrix based on a seed value and/or may select the matrix from among a set of bijective matrices. In some examples, the bijective matrix may have at least one column and/or one row that has at least two non-zero elements. The device may generate a first address of a first address space based on applying the matrix (e.g., each column of the matrix) to at least a portion of a second address of a second address space and may access a memory array of the device based on generating the first address.

Address scrambling by linear maps in Galois fields

Systems, apparatuses, and methods related to memory bank protection are described. A quantity of errors within a single memory bank is determined and the determined quantity can be used to further determine whether to access other memory banks to correct the determined quantity. The memory bank protection described herein avoids a single memory bank of a memory die being a single point of failure (SPOF).

Memory bank protection

The present disclosure includes apparatuses, methods, and systems for drift compensation for codewords in memory. An embodiment includes a memory device having an array of memory cells, and circuitry to sense a codeword stored in the array, determine a derivative value of a cell metric for each cell of the codeword based on a threshold voltage of that respective cell, a mean of threshold voltage values of each cell of the codeword, and a value proportional to a total quantity of the cells of the codeword and a position of the threshold voltage value of that respective cell in the threshold voltage values of each cell of the codeword, determine the cell metric for which the determined derivative value changes from a first polarity to a second polarity, input the determined cell metric to a Pearson detector, and determine originally programmed data of the codeword using the Pearson detector.

Drift compensation for codewords in memory

Methods, systems, and devices related to auto-referenced memory cell read techniques are described. The auto-referenced read may encode user data to include a predetermined number of bits having a first logic state prior to storing the user data in memory cells. The auto-referenced read may store a total number of bits of the user data having a first logic state in a separate set of memory cells. Subsequently, reading the user data may be carried out by applying a read voltage to the memory cells storing the user data while monitoring a series of switching events by activating a subset of the memory cells having the first logic state. During the read operation, the auto-referenced read may compare the number of activated memory cells to either the predetermined number or the total number to determine whether all the bits having the first logic state has been detected. When the number of activated memory cells matches either the predetermined number or the total number, the auto-referenced read may determine that the memory cells that have been activated correspond to the first logic state.

Auto-referenced memory cell read techniques

A memory device can include a plurality of memory cells including a first group of memory cells and a second group of memory cells programmed to a predefined logic state. The plurality of memory cells includes a memory controller configured to apply a reading voltage to at least one selected memory cell of the first group during a reading operation, apply the reading voltage to the memory cells of the second group, and responsive to the logic state of at least one memory cell of the second group being assessed to be different from the predefined logic state perform a refresh operation of the memory cells of the first group by applying a recovery voltage higher than the reading voltage to assess the logic state thereof and reprogramming the memory cells of the first group to the logic state assessed with the recovery voltage.

Memory device and method for operating the same including setting a recovery voltage

A channel width can depend on a quantity of memory units (e.g., memory dice) that forms a channel as well as a size of the memory units. A memory system can operate with memory units configured to exchange (e.g., transfer to and/or from) data at a rate of smaller granularity that can provide more various options for channel widths, which can further allow a fine-tuned optimization of the memory system in association with its bandwidth and latency in transferring data from and/or to the memory units. The channels whose channel width is fine-tuned with such memory units can be further used to provide a reliability, availability, and serviceability (RAS) protection, such as a redundant array of independent disks (RAID) protection.

Apparatus for redundant array of independent disks

Data protection with error correction/detection capabilities can be provided on a cache line basis. When provided on a cache line basis to collectively protect the cache line data, the error correction/detection capabilities can be provided with fewer number of bits (e.g., error correction code (ECC) and/or cyclic redundancy check (CRC) bits) as compared to providing the same error correction/detection capabilities individually on a subset of the cache line data.

Cache line data protection

An on-die controller can provide an error correction capability for data stored in an array of memory cells located on the same die as the on-die controller. The error correction capability provided by the on-die controller eliminates a need to transfer error correction code (ECC) data to an external controller that may have provided the error correction capability in lieu of the on-die controller, which can provide more channel bandwidth for other types of non-user data for further strengthening data reliability, security, integrity of the memory system.

Intra-controllers for error correction code

Methods, systems, and devices for data correction schemes with reduced device overhead are described. A memory system may include a set of memory devices storing data and check codes associated with the data. The memory system may additionally include a single parity device storing parity information associated with the data. During a read operation of a set of data, a controller of the memory system may detect an error in data associated with a first check code, the data including two or more subsets of the set of data received from two or more corresponding memory devices. The controller may generate candidate data corresponding to one of the two or more subsets using the parity information and remaining subsets of the set of data. Then the controller may determine whether the candidate data is correct by comparing the first check code with a check value generated using the candidate data.

Data correction scheme with reduced device overhead

Systems, apparatuses, and methods related to a flip-on-precharge disable operation are described herein. In an example, a method can include receiving a command to perform a precharge operation on a set of memory cells in a memory device. The memory device can include a plurality of sets of memory cells corresponding to respective portions of an array of memory cells of the memory device. The method can further include accessing one or more sets of bits in a mode register. The one or more sets of bits in the mode register indicate address locations of the plurality of sets of memory cells to disable the flip on precharge operation. The method can further include performing the precharge operation on the set of memory cells. The flip on precharge operation associated with the precharge operation can be disabled for those sets of the plurality of sets of memory cells whose address locations are in the mode register.

Adjustable memory cell reliability management

Systems, methods, and apparatuses are provided for drift compensation for codewords in memory. A memory device comprises memory cells and circuitry configured to sense a codeword stored in the array of memory cells using a reference voltage and determine an amount by which to adjust the reference voltage used to sense the codeword based on an estimated weight of the original codeword, a mean of threshold voltage values of each memory cell of the sensed codeword, and a total quantity of memory cells of the sensed codeword. The circuitry can further be configured to adjust the reference voltage used to sense the codeword by the determined amount.

Systems, apparatuses, and methods related to a flip-on-precharge disable operation are described herein. In an example, a flip-on-precharge disable operation can include activating a set of memory cells in a memory device to perform a memory access. The memory device can include a plurality of sets of memory cells corresponding to respective portions of an array of memory cells of the memory device. The flip-on-precharge disable operation can further include receiving signaling indicative of a command for a precharge operation on a set of the plurality of sets of memory cells. The signaling can include one or more bits that indicates whether to disable a randomly performed flip operation on the set of memory cells. The flip-on-precharge disable operation can include, in response to the one or more bits indicating to disable the flip operation, performing the precharge operation without randomly performing the flip operation on the set of memory cells.

Strategic memory cell reliability management

Systems, apparatuses, and methods related to a controller for managing multiple types of memory are described. A controller includes a front end portion, a central controller portion, a back end portion, and a management unit can manage a first type of memory device that operates according to a first set of timing characteristics and a second type of memory device that operates according to a second set of timing characteristics. The central controller portion is configured to cause performance of a memory operation and comprises a cache memory to buffer data associated performance of the memory operation, a security component configured to encrypt the data before storing the data in the first type of memory device or the second type of memory device, and error correction code (ECC) circuitry to ECC encode and ECC decode the data.

Controller for managing multiple types of memory

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Cernusco sul Naviglio, Italy

Marco Sforzin