Abstract: Described are memory devices producing metadata characterizing the applied read voltage level with respect to voltage distributions. An example memory sub-system comprises: a memory device comprising a plurality of memory cells; and a controller coupled to the memory device, the controller to perform operations comprising: performing, using a read voltage level, a read strobe with respect to a subset of the plurality of memory cells; and receiving, from the memory device, one or more metadata values characterizing the read voltage level with respect to threshold voltage distributions of the subset of the plurality of memory cells, wherein the one or more metadata values reflect a conductive state of one or more bitlines connected to the subset of the plurality of memory cells.

Abstract: In a memory sub-system, data can be received to be stored at a 3-dimensional (3D) memory component in response to a write operation. A first location of a first layer of the 3D memory component is determined at which to store a first portion of the data, where the first layer is within a first logical unit. A second location of a second layer of the 3D memory component is determined at which to store a second portion of the data, where the second layer is within a second logical unit that is different than the first logical unit. The first portion of the data is caused to be stored in first memory cells at the first location within the first layer. The second portion of the data is caused to be stored in second memory cells at the second location within the second layer.

Abstract: Methods, systems, and devices for a corrective read of a memory device with reduced latency are described. A memory system may identify a read error based on accessing a memory device, and may select a trim setting for a performing a corrective read operation based on a data retention condition associated with the accessed memory device. Such a data retention condition may be associated with a data retention duration, or a cross-temperature condition, among other criteria or combinations thereof. In some implementations, the memory system may select from a subset of possible trim settings, which may be associated with relevant process corners. For example, the memory system may select between a first trim setting that is associated with a relatively large cross-temperature and a relatively short data retention duration and a second trim setting that is associated with a relatively small cross-temperature and a relatively long data retention duration.

Abstract: A method may comprise detecting an error associated with accessing a set of data items. The set of data items are programmed to a respective memory page associated with a stripe of a plurality of stripes. In response to determining that the set of data items comprises one or more codewords, a first data recovery process is performed to recover the one or more codewords based at least in part on RAIN redundancy metadata. In response to determining that the set of data items comprises additional parity metadata, a second data recovery process is performed to recover the additional parity metadata based at least in part on LUN redundancy metadata. In response to determining that the set of data items comprises RAIN redundancy metadata, a first data reconstruction process is performed to regenerate the RAIN redundancy metadata based at least in part on one or more sets of codewords.

Abstract: Described are systems and methods for memory read calibration based on memory device-originated metrics characterizing voltage distributions. An example memory device includes: a memory array having a plurality of memory cells and a controller coupled to the memory array. The controller is to perform operations including: receiving a first metric characterizing threshold voltage distributions of a subset of the plurality of memory cells; determining a first read voltage adjustment; receiving a second metric characterizing the threshold voltage distributions; determining a second read voltage adjustment; and applying the second read voltage adjustment for reading the subset of the plurality of memory cells.

Abstract: Codewords of an error correcting code can be received. The codewords can be separated into multiple segments. The segments of the codewords can be distributed in an error correcting layout across a plurality of dies where at least a portion of the error correcting (EC) layout constitutes a first layout in the form of a Latin Square.

Abstract: A processing device in a memory sub-system receives a request to perform a memory access operation on a memory device, determines a memory segment identifier associated with the memory access operation, and applies a hash function to the memory segment identifier to generate a hashed seed. The processing device further provides the hashed seed to a pseudo-random number generator to generate a randomized string, and performs the memory access operation on the memory device using the randomized string.

Abstract: A processing device in a memory sub-system determines a syndrome weight for a sense word read from a memory device and determines whether the syndrome weight for the sense word satisfies a threshold criterion. Responsive to the syndrome weight for the sense word satisfying a respective threshold criterion associated with a next iteration of a first decoding operation, bypassing the first decoding operation and initiating a second decoding operation for the sense word, wherein the second decoding operation has a higher error correction capability than the first decoding operation.

Abstract: Described are systems and methods for memory read calibration based on memory device-originated metadata characterizing voltage distributions. An example memory device comprises: a memory array comprising a plurality of memory cells electrically coupled to a plurality of wordlines; and a controller coupled to the memory array, the controller to perform operations comprising: receiving one or more metadata values characterizing threshold voltage distributions of a subset of the plurality of memory cells connected to one or more bitlines, wherein the one or more metadata values reflect a conductive state of the one or more bitlines; determining a read voltage adjustment value based on the one or more metadata values; and applying the read voltage adjustment value for reading the subset of the plurality of memory cells.

Abstract: Methods, systems, and devices for a dynamic error control configuration for memory systems are described. The memory system may receive a read command and retrieve a set of data from a location of the memory system based on the read command. The memory system may perform a first type of error control operation on the set of data to determine whether the set of data includes one or more errors. If the set of data includes the one or more errors, the memory system may retrieve a second set of data from the location of the memory system and determine whether a syndrome weight satisfies a threshold. The memory system may perform a second type of error control operation on the second set of data based on determining that the syndrome weight satisfies the threshold.

Abstract: Disclosed in some examples are methods, systems, devices, and machine-readable mediums that provide for techniques for scrambling and/or updating meta-data that enable an efficient internal copyback operation. In some examples, improved data distribution techniques decouple the scrambling key from a physical address to allow for copyback operations while maintaining data distribution requirements across a memory device. The controller may generate a seed value that is used by a scrambling algorithm to scramble the host-data and meta-data prior to the data being written. The seed value is then encoded and written to the page with encoded versions of the scrambled user data and meta-data—the random seed is written without scrambling the random seed.

Abstract: A plurality of codewords are programmed to one or more memory pages of a memory sub-system. Each memory page of the memory sub-system is associated with a logical unit of a plurality of logical units of the memory sub-system and at least one of a plane of a plurality of planes of the memory sub-system or a block of a plurality of blocks of the memory sub-system. Each codeword of the plurality of codewords comprises host data and base parity bits. A plurality of additional parity bits are programmed to the one or more memory pages of the memory sub-system, wherein each additional parity bit of the plurality of additional parity bits is associated with a codeword of the plurality of standard codewords. A first set of redundancy metadata is generated corresponding to each of the additional parity bits. The first set of redundancy metadata is programmed to a memory page separate from any memory page storing the additional parity bits.

Abstract: Disclosed in some examples are methods, systems, devices, and machine-readable mediums that provide for techniques for scrambling and/or updating meta-data that enable an efficient internal copyback operation. In some examples, in order to update the meta-data, the meta-data and host-data are separated and the only the meta-data is sent to the controller to be updated during a modified internal copyback operation. The host-data is not transmitted to the controller. While sending the meta-data utilizes resources of the communication link between the memory dies and the controller, it uses much fewer resources than if the host-data were also transmitted.

Abstract: A processing device in a memory system reads a sense word from a memory device and executes a plurality of parity check equations on corresponding subsets of the sense word to determine a plurality of parity check equation results. The processing device determines a syndrome for the sense word using the plurality of parity check equation results, determines whether the syndrome for the sense word satisfies a codeword criterion, and responsive to the syndrome for the sense word not satisfying the codeword criterion, performs an iterative low density parity check (LDPC) correction process, wherein at least one criterion of the iterative LDPC correction process is adjusted after a threshold number of iterations is performed.

Abstract: A method includes determining one or more quality attributes for memory cells of a memory device, receiving a memory access request involving data written to at least a portion of the memory cells, and determining whether the memory access request corresponds to a random read operation or a sequential read operation. The method further includes responsive to determining that the memory access request corresponds to a random read operation or responsive to determining that the one or more quality attributes for memory cells are greater than a threshold quality level, or both, selecting a read mode for use in performance of the random read operation and performing the random read operation using the selected read mode.

Abstract: Disclosed in some examples are methods, systems, devices, and machine-readable mediums that provide for techniques for scrambling and/or updating meta-data that enable an efficient internal copyback operation. In some examples, improved data distribution techniques decouple the scrambling key from a physical address to allow for copyback operations while maintaining data distribution requirements across a memory device. The controller may generate a seed value that is used by a scrambling algorithm to scramble the host-data and meta-data prior to the data being written. The seed value is then encoded and written to the page with encoded versions of the scrambled user data and meta-data—the random seed is written without scrambling the random seed.

Abstract: A processing device in a memory system determines a first error rate corresponding to a first set of write-to-read delay times at a first end of a range of write-to-read delay times for a memory device and a second error rate corresponding to a second set of write-to-read delay times at a second end of the range of write-to-read delay times, and determines whether a ratio of the first error rate to the second error rate satisfies a threshold criterion.

Abstract: Described herein are embodiments related to defect detection in memory components of memory systems with time-varying bit error rate. A processing device determines that a bit error rate (BER) corresponding to a read operation to read a unit of data in a memory component satisfies a threshold criterion, determines a write-to-read (W2R) delay for the read operation, wherein the W2R delay comprises a difference between a time of the read operation and a write timestamp indicating when the unit of data was written to the memory component, and determines whether the W2R delay is within a W2R delay range corresponding to an initial read voltage level used by the read operation to read the unit of data. The processing device initiates a defect detection operation responsive to the W2R delay being within the W2R delay range, the defect detection operation to detect time-varying defects in the memory component.

Abstract: Methods, systems, and devices for a corrective read of a memory device with reduced latency are described. A memory system may identify a read error based on accessing a memory device, and may select a trim setting for a performing a corrective read operation based on a data retention condition associated with the accessed memory device. Such a data retention condition may be associated with a data retention duration, or a cross-temperature condition, among other criteria or combinations thereof. In some implementations, the memory system may select from a subset of possible trim settings, which may be associated with relevant process corners. For example, the memory system may select between a first trim setting that is associated with a relatively large cross-temperature and a relatively short data retention duration and a second trim setting that is associated with a relatively small cross-temperature and a relatively long data retention duration.

Abstract: A processing device in a memory system receives a request to read data from a memory device. In response to receiving the request, the processing device performs an iterative error correction process on the data, wherein at least one iteration after a first iteration in the error correction process uses a criterion that is based at least partially on a previous iteration or partial iteration, and wherein performing the iterative error correction process comprises flipping any bits in the data having an associated number of unsatisfied parity check equations that satisfies a threshold criterion associated with the previous iteration.