Kabushiki Kaisha Toshiba

Tarou Iwashiro

Kenji Sakaue

Yoshihisa Kondo

Masaru Ogawa

Seiichi Tomita

Takahide Nishiyama

According to one embodiment, a memory system includes a memory cell array, first error correction part, second error correction part, and third error correction part. The memory cell array includes a first storage area in which 1-bit data is stored in one memory cell, and second storage area in which data of a plurality of bits is stored in one memory cell. When data is written to the first storage area, the first error correction part generates first parity data in the row direction on the basis of the data described above. The second error correction part corrects an error of the data described above on the basis of the first parity data read from the memory cell array. The third error correction part generates second parity data in the column direction on the basis of data of a plurality of pages.

Nonvolatile semiconductor memory system error correction capability of which is improved

According to one embodiment, a memory device includes a semiconductor memory and a controller that controls the semiconductor memory. The controller includes a first command issuing module, second command issuing module, error correction module and control module. The first command issuing module is configured to issue a read command to the semiconductor memory. The second command issuing module is configured to issue a first command instructing a process that does not involve reading data from the semiconductor memory independently from the first command issuing module to the semiconductor memory. The error correction module is configured to correct an error contained in data supplied from the semiconductor memory. The control module is configured to control the error correction module, first command issuing module and second command issuing module.

Memory device

A controller includes an instruction table memory, a program counter, a first decoder, and a first executing unit. The instruction table memory stores an instruction code obtained by coding a sequence to access a nonvolatile semiconductor memory. A read address in the instruction table memory is set to the program counter. The first decoder decodes the instruction code read from the instruction table memory to output a first decode signal. The first executing unit executes access to the nonvolatile semiconductor memory on the basis of the first decode signal output from the first decoder.

Controller which controls operation of nonvolatile semiconductor memory and semiconductor memory device including nonvolatile semiconductor memory and controller therefore

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Yokohama, Japan

Tarou Iwashiro