Micron Technology Incorporated

Deping He

Qing Liang

Jonathan Scott Parry

David Aaron Palmer

Chun Sum Yeung

Giuseppe Cariello

Caixia Yang

Harish Reddy Singidi

Xiangang Luo

Nadav Grosz

Jianmin Huang

Ting Luo

Kulachet Tanpairoj

Preston Allen Thomson

Scott Anthony Stoller

Devin M Batutis

Luca Porzio

Jeffrey Alan Kessenich

Taehoon Kim

Min Rui Ma

John Zhang

Jingyuan Miao

Sampath K Ratnam

Zhengang Chen

Ching-Huang Lu

Reshmi Basu

Hua Fang Tan

Xing Wang

Guang Hu

Lavanya Sriram

Xiaolai Zhu

Jun Huang

Wenjun Wu

Junjun Wang

Bo Zhou

Hong Lu

Bhagyashree Bokade

Yanming Liu

Violet Gomm

Mingke Yu

Methods, systems, and devices for critical data management within a memory system are described. A memory system may avoid writing critical data to weak word lines. For example, as part of a media management operation or a host write operation (among other examples), the memory system may determine which data is critical data and may determine which word lines are weak word lines, which may refer to word lines having bit error rates that satisfy a threshold. The memory system may refrain from writing critical data to memory cells coupled with weak word lines, and may instead write non-critical or dummy data to the weak word lines. The memory system may reserve the writing of critical data to memory cells coupled with non-weak word lines, which may refer to word lines having bit error rates that fail to satisfy the threshold.

Critical data management within a memory system

Methods, systems, and devices for write booster buffer and hibernate are described. The memory system may initiate a first operation to enter a first power mode having a lower power consumption than a second power mode. In some cases, the memory system may determine whether a quantity of data stored in a buffer of single-level cells associated with write booster information satisfies a threshold based on initiating the first operation. The memory system may determine whether to perform a second operation to transfer the quantity of data stored in the buffer of single-level cells to a portion of memory comprising multiple level cells based on determining whether the quantity of data satisfies the threshold. The memory system may enter the first power mode based on determining to perform the second operation to transfer the quantity of data from the buffer to the portion of memory.

Write booster buffer and hibernate

Methods, systems, and devices for shallow hibernate power state are described. A memory system may include a memory array and a controller. The memory system may transition from a first power state having a first current to a second power state having a second current less than the first current, where the first power state is associated with executing received commands and the second power state is associated with deactivating one or more components of the memory array. The memory system may initiate a timer after transitioning from the first power state to the second power state. The memory system may determine the timer satisfies a threshold and transition from the second power state to a third power state having a third current less than the second current based on the timer satisfying the threshold.

Shallow hibernate power state

A memory device includes a memory array comprising memory cells associated with a plurality of wordlines control logic that is to perform operations including: causing memory cells of a physical unit of the memory array to be programmed starting at a second wordline, which is adjacent to a first wordline of the memory array, and proceeding sequentially through a plurality of sequentially-ordered wordlines of the physical unit, wherein the first wordline is associated with memory cells that are adjacent to one or more select gate (SG) transistors of the memory array, and the sequentially-ordered wordlines are numbered according to a distance away from the one or more SG transistors; and at least one of after the memory cells associated with the second wordline are programmed or after completion of programming the physical unit, causing the memory cells associated with the first wordline to be programmed.

Out-of-order programming of first wordline in a physical unit of a memory device

Methods, systems, and devices for techniques for enhanced system performance after retention loss are described. A memory system may program a page of memory cells in response to receiving a power down notification. As part of the programming, the memory system may record an indication of a voltage threshold of the page and power down for a duration of time, during which the memory system may experience retention loss. Upon powering on, the memory device may compare the voltage threshold of the page to the indication stored prior to powering down and determine a voltage offset for one or more blocks of the memory system. In some cases, the memory system may use the voltage offset to determine a starting bin, and may initiate a bin scan to determine a final bin for the one or more blocks.

Techniques for enhanced system performance after retention loss

Methods, systems, and devices for topology-based retirement in a memory system are described. In some examples, a memory system or memory device may be configured to evaluate error conditions relative to a physical or electrical organization of a memory array, which may support inferring the presence or absence of defects in one or more structures of a memory device. For example, based on various evaluations of detected errors, a memory system or a memory device may be able to infer a presence of a short-circuit, an open circuit, a dielectric breakdown, or other defects of a memory array that may be related to wear or degradation over time, and retire a portion of a memory array based on such an inference.

Topology-based retirement in a memory system

Methods, systems, and devices for data compression for mapping tables are described. A memory system may store a table that includes mappings between a set of logical block addresses and a set of physical block addresses. The table may be stored to volatile memory of the memory system and each entry may include a subset of physical block addresses and one or more logical block addresses that correspond to the subset of physical block addresses. In some implementations, a quantity of the entries that each include the subset of physical block addresses and the one or more logical block addresses may be determined based on dividing the set of physical block addresses by a factor. Similarly, a size of the entries may be determined based on dividing the set of physical block addresses by the factor.

Data compression for mapping tables

Methods, systems, and devices for techniques for retiring blocks of a memory system are described. In some examples, aspects of a memory system or memory device may be configured to determine an error for a block of memory cells. Upon determining the occurrence of the error, the memory system may identify one or more operating conditions associated with the block. For example, the memory system may determine a temperature of the block, a cycle count of the block, a quantity of times the block has experienced an error, a bit error rate of the block, and/or a quantity of available blocks in the associated system. Depending on whether a criteria associated with a respective operating condition is satisfied, the block may be enabled or retired.

Techniques for retiring blocks of a memory system

Methods, systems, and devices for suspension during a multi-plane write procedure are described. A memory system may perform a multi-plane write procedure by writing to a set of planes in parallel. Upon detecting a defective plane in the set of planes, the memory system may suspend writing to the defective plane until writing to the other planes in the set of planes is finished. The memory system may then resume writing to the defective plane.

Suspension during a multi-plane write procedure

Methods, systems, and devices for enhanced data reliability in multi-level memory cells are described. For a write operation, a host device may identify a first set of data to be stored by a set of memory cells at a memory device. Based on a quantity of bits within the first set of data being less than a storage capacity of the set of memory cells, the host device may generate a second set of data and transmit a write command including the first and second sets of data to the memory device. For a read operation, the host device may receive a first set of data from the memory device in response to transmitting a read command. The memory device may extract a second set of data from the first set of data and validate a portion of the first set of data using the second set of data.

Enhanced data reliability in multi-level memory cells

A memory sub-system to initiate an erase operation to erase a first set of memory cells of a first memory block and a second set of memory cells of a second memory block of a memory device. One or more erase pulses of the erase operation are caused to be applied to the first set of memory cells of the first memory block and the second set of memory cells of the second memory block concurrently. A first erase verify sub-operation of the erase operation is caused to be performed to verify the first memory block is erased and a second erase verify sub-operation of the erase operation is caused to be performed to verify the second memory block is erased.

Multiple memory block erase operation

A method includes writing, to a first data structure, indices corresponding to address locations of a logical-to-physical (L2P) data structure that maps a plurality of logical block addresses (LBAs) associated with the L2P data structure, initiating performance of a media management operation involving one or more memory blocks in which data associated with the LBAs is written, and refraining from rewriting particular entries in the L2P table that correspond to LBAs whose index in the first data structure is a particular value during performance of the media management operation.

Virtual indexing in a memory device

Methods, systems, and devices for cache block budgeting techniques are described. In some memory systems, a controller may configure a memory device with a cache. The cache may include a first subset of blocks configured to statically operate in a first mode and a second subset of blocks configured to dynamically switch between operating in the first mode and a second mode. A block operating in the second mode may be configured to store relatively more bits per memory cell than a block operating in the first mode. The controller may track and store, for each block of the second subset of blocks, a respective ratio of cycles performed in the first mode to cycles performed in the second mode. The controller may select a block from the second subset of blocks to switch between modes responsive to a trigger and based on the respective ratio for the block.

Cache block budgeting techniques

Methods, systems, and devices for commands to support adaptive memory systems are described. A memory system may be configured to receive a command to perform an operation on an address of a memory system, the command including an indication of a count of program/erase cycles associated with the address; determine whether the count of program/erase cycles associated with the address satisfies a threshold; adjust a trim parameter for operating the memory system based at least in part on determining that the indication of the count of program/erase cycles satisfies the threshold; and perform the operation associated with the command using the adjusted trim parameter.

Command sequence to support adaptive memory systems

Techniques for access operation status signaling for memory systems are described. In some examples, a memory system may respond to access commands from a host system by performing access operations such as read or write operations. In accordance with examples as disclosed herein, a system may be configured to support access operation status signaling between a host system and a memory system, which may improve the ability of the system to adapt to various access scenarios, including when access operation completion is delayed. For example, when a memory system is performing an error recovery or media management operation, the memory system may indicate that the error recovery or media management operation is being performed or is otherwise ongoing. Such status signaling may indicate that the memory system is actively performing operations, which may be used to inhibit a reset or reinitialization by a host system.

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Boise, ID, United States of America

Deping He