Kabushiki Kaisha Toshiba

Toshiba Memory Corporation

Kioxia Corporation

Hiroki Matsudaira

Ryuji Nishikubo

Kosuke Hatsuda

Hidenori Matsuzaki

Junji Yano

Norio Aoyama

Takashi Hirao

Hirokuni Yano

Mitsunori Tadokoro

Aurelien Nam Phong Tran

Kenji Tanaka

Atsushi Okamoto

Hiroyuki Yamaguchi

Shinji Yonezawa

Akira Sawaoka

Ryoichi Kato

Tatsuya Sumiyoshi

Yoshimi Niisato

Eiji Yoshihashi

A memory system according to an embodiment includes a nonvolatile memory and a memory controller. The nonvolatile memory includes a first storage region and a second storage region. The memory controller comprises a third storage region storing a master table and a fourth storage region storing a change history of the master table. The memory controller is configured to: order the nonvolatile memory to write the master table stored in the third storage region in the first storage region when receiving a power-off command from outside; order the nonvolatile memory to write the change history stored in the fourth storage region in the second storage region.

Memory system and control method thereof

A memory system comprises a first memory including physical blocks, a second memory storing a first correspondence table in which a logical cluster address corresponding to an address assigned to data received from a host is correlated with a logical group number corresponding to a block group and a logical cluster number corresponding to a location within the block group, and a second correspondence table in which first physical block numbers corresponding to first physical blocks are correlated with a first logical group number and second physical block numbers corresponding to second physical blocks are correlated with a second logical group number, and a controller circuit that updates the first correspondence table when new data is written to the first physical blocks, and the second correspondence table, without changing the first corresponding table, when data is moved from the first to the second physical blocks.

Memory system having first and second correspondence tables and method of controlling memory system

According to one embodiment, a memory system writes data to a first block, and executes a garbage collection when the number of free blocks is not greater than a first threshold value. The memory system calculates a first number which is a ratio of the number of copy destination blocks needed for the garbage collection to the number of blocks to which data designated by a write command is written. The memory system determines whether the first number is greater than a second threshold value when a first command is received from the host, and performs fill-up processing for the first block when the first number is not greater than the second threshold value.

Memory system and control method of the same

According to one embodiment, a memory system includes a nonvolatile memory including a plurality of blocks, and a controller controlling the nonvolatile memory. The controller cyclically executes patrol read, the patrol read including reading data and testing the read data, the read data being data of pages connected to some of word lines in each of the blocks of the nonvolatile memory.

Memory system and method of controlling memory system

According to one embodiment, a memory system includes non-volatile memory, a block management table that stores whether data in the non-volatile memory is valid or invalid in a unit of cluster, and a controller configured to execute compaction. In the block management table, first information related to likelihood that valid data within the block is invalidated is registered for each of the blocks. The controller is configured to select a block to be a target of the compaction based on the first information and use the selected block to execute the compaction.

Memory system, controller and control method of memory

A memory system in embodiments includes a nonvolatile semiconductor memory that stores user data, a forward lookup address translation table and a reverse lookup address translation table, and a controller. The controller is configured to determine that the user data stored in the nonvolatile semiconductor memory is valid or invalid based on these two tables. The controller may perform data organizing of selecting data determined valid and rewriting the data in a new block. The controller may perform write processing and rewriting processing to the new block alternately at a predetermined ratio. The controller may determine whether a predetermined condition is satisfied on a basis of addresses included in write requests and write data in the MLC mode when the condition is satisfied and write data in the SLC mode when the condition is not satisfied.

Memory system and control method of memory system

A controller performs a coding process based on a first frame including data of a plurality of pages connected to first word lines being a predetermined number of consecutive word lines in a block, and performs, when padding data is written to a plurality of pages connected to second word lines being the predetermined number of word lines subsequent to the first word lines, the coding process based on a second frame obtained by excluding the padding data from a frame including data of the pages connected to the second word lines.

A memory system includes a controlling unit that configured to control data transfer between the first and the second memory. The controlling unit executes copy processing for, after reading out data stored in a first page of the second memory to the first memory, writing the data in a second page of the second memory, determines, when executing the copy processing, whether the error correction processing for the data read out from the first page is successful, stores, when the error correction processing is successful, corrected data in the first memory and writes the corrected data in the second page, and reads out, when the error correction processing is unsuccessful, the data from the first page to the first memory and writes the data not subjected to the error correction processing in the second page.

Memory system configured to control data transfer

According to one embodiment, a memory system includes a non-volatile memory, a volatile memory, a controller, and a compression/decompression processor. When data transmission is performed through the volatile memory between a host apparatus and the non-volatile memory, the controller updates management information stored in the volatile memory. In addition, the compression/decompression processor compresses the management information in the case where a first condition is satisfied, and decompresses the compressed management information in the case where a second condition is satisfied. The controller stores the compressed management information in the non-volatile memory.

Memory system, data management method, and computer

A management information generating method wherein logical and physical block addresses (BAs) of continuous addresses are associated with each other in the BA translation table. When a logical block is constructed, a value is set for a maximum number of allowable defective physical blocks. A logical block having fewer defects than the set number is set usable, and a logical block having more defects than the set number is set unusable. System logical block construction is performed to preferentially select physical blocks from a plane list including a large number of usable blocks to equalize the number of usable blocks in each plane list. It is determined whether the number of free blocks is insufficient on the basis of a first management unit and whether the storage area for the indicated capacity can be reserved on the basis of the management unit different from the first unit.

Management information generating method, logical block constructing method, and semiconductor memory device

Nonvolatile semiconductor memory system configured to control data transfer

A memory system includes a controller that manages data stored in the first and second storing areas. The controller determines, when a readout error occurs when the stored data in the second storing area is read out, success or failure of error correction to the read-out data based on the result of the error correction stored in a storage buffer, writes, when the error correction is successful, correction data corresponding to the read-out data stored in the storage buffer, and writes, when the error correction fails, the read-out data itself not subjected to error correction processing.

Memory system

To provide a memory system that can surely restore management information even when a program error occurs during data writing. After 'log writing ()' for a pre-log, when a program error occurs when data writing is being performed (a data writing error), the memory system performs the data writing again without acquiring a pre-log corresponding to data rewriting processing. After finishing the data writing, the memory system acquires, without generating a post-log, a snapshot instead of the post-log and finishes the processing.

Growing community of inventors

Funabashi, Japan

Hiroki Matsudaira