Kabushiki Kaisha Toshiba

Kioxia Corporation

Toshiba Memory Corporation

Mitsuaki Honma

Noboru Shibata

Hironori Uchikawa

Tatsuyuki Ishikawa

Katsuaki Isobe

Akio Sugahara

Yoshikazu Takeyama

Daisuke Arizono

Yuko Namiki

Mitsuhiro Abe

Tomoko Araya

Shinji Saito

Naoki Kobayashi

Takuya Futatsuyama

Yoshikazu Harada

Yasuhiro Hirashima

Kazunori Kanebako

Mikio Ogawa

Kiyoaki Iwasa

Hayao Kasai

Osamu Nagao

Keisuke Azuma

According to an embodiment, a memory system comprising: a non-volatile memory including a plurality of memory cells each capable of storing at least a first bit and a second bit, and configured to calculate third soft bit data based on a logical sum calculation using at least first soft bit data corresponding to the first bit and second soft bit data corresponding to the second bit; and a memory controller configured to restore the first soft bit data and the second soft bit data based on at least first hard bit data corresponding to the first bit, second hard bit data corresponding to the second bit, and the third soft bit data.

Memory system and non-volatile memory using soft bit data information to improve memory operation

According to one embodiment, a memory device is configured to execute an efficient read operation is provided. The memory device includes a plurality of memory cells, a word line, and a controller. Each of the memory cells stores first to fifth bit data based on the threshold voltage. The memory cells store a first page to a fifth page respectively corresponding to the first bit data to the fifth bit data. A word line is coupled to the memory cells. A controller executes a read operation for reading data from the memory cells by applying a read voltage to the word line. Numbers of times the controller applies read voltages different from one another to the word line in read operations for the first page to the fifth page are 7, 6, 6, 6, and 6, respectively.

Memory device applying plural different read voltages to a word line in a read operation

A memory system includes a plurality of memory cells each storing a first bit and a second bit and a control circuit. The control circuit is reads out first data, first partial data, and second partial data, each corresponding to the first bit, from the plurality of memory cells, read out second data, third partial data, and fourth partial data, each corresponding to the second bit, from the plurality of memory cells, generate first compressed data based on an OR operation of the first partial data and the third partial data, generate second compressed data based on an OR operation of the second partial data and the fourth partial data, and transmit the first data, the second data, the first compressed data, and the second compressed data to an external memory controller.

Non-volatile memory and memory system

A semiconductor memory device includes a first pad, a clock generation circuit configured to generate a first clock, an output circuit configured to output the first clock through the first pad, a designation circuit configured to designate one of a plurality of contiguous times slots, each of which is set with respect to clock cycles of the first clock, and a peak control circuit configured to execute an operation that generates a current peak, at a timing corresponding to the designated time slot.

Semiconductor memory device and memory system

A semiconductor memory device includes: a core unit including first and second memory cell groups; and a control circuit. The control circuit is configured to, in response to a read command including designation of a first address and designation of a second address, read first data from the first memory cell group, read second data from the second memory cell group, and output third data and fourth data in parallel. The first and second addresses correspond to the first and second memory cell groups, respectively. The designation of the second address is made after the designation of the first address. The third data corresponds to the read first data. The fourth data corresponds to the read second data.

Semiconductor memory device outputting data from memory cell groups in parallel and system

According to one embodiment, a memory device, includes a first memory cell, and a second memory cell adjacent to the first memory cell; and a sequencer configured to, when data is read from the first memory cell: perform a first read operation on the second memory cell; perform a second read operation on the first memory cell; perform a third read operation on the first memory cell by applying a voltage different from that applied in the second read operation to a gate of the second memory cell; and generate first data stored in the first memory cell and second data for correcting the first data, based on results of the first to third read operations.

Memory device

According to one embodiment, a semiconductor memory device includes a memory cell, a bit line, a sense amplifier, a word line, and a row decoder. A write operation repeats a program loop including a program operation, first and second verify operations. The row decoder applies a first read voltage to the word line in the first and second verify operations. When the write operation is not suspended, the sense amplifier senses a voltage of the bit line for a first sense period in the first verify operation. When the write operation is suspended, the sense amplifier senses the voltage of the bit line for a second sense period shorter than the first sense period in the initial first verify operation after a resumption of the write operation.

Semiconductor memory device

A memory system includes a semiconductor memory device having a memory cell array including a first area and a second area, and a controller configured to issue to the semiconductor memory device a first command designating reading of data from the first area using a first data reading scheme and a flag status associated with the data. If the flag status indicates the data is in a first state, the controller issues the second command to cause the data to be output from the semiconductor memory device to the controller. If the flag status indicates the data is in a second state, the controller issues the third command to cause the data to be transferred from the first area to the second area.

According to one embodiment, the semiconductor memory device includes a first memory cell and a word line. The first memory cell is capable of storing two or more bits of data. The word line is coupled with the first memory cell. a write operation repeat a program loop. The program loop includes a program operation and a verification operation. A program voltage is applied to the word line in the program operation. The write operation includes a first program loop and a second program loop subsequent to the first program loop. Program voltage is applied a first number of times in the first program loop. Program voltage is applied a second number of times in the second program loop. The second number of times is larger than the first number of times.

According to one embodiment, a nonvolatile semiconductor memory device includes a memory cell array and a controller. The controller is configured to perform a verify operation using a first verification voltage and a second verification voltage (first verification voltage&#x3c;second verification voltage) when first value data is stored in a first memory cell. The controller is configured to determine whether a write operation to the first memory cell is completed or continued based on write data of a second memory cell adjacent to the first memory cell when a threshold voltage of the first memory cell is greater than or equal to the first verification voltage and less than the second verification voltage.

Nonvolatile semiconductor memory device

According to one embodiment, a nonvolatile semiconductor memory device includes a memory cell array, a bit line, and a voltage generator. The memory cell array includes each of a plurality of memory cells. Each of the memory cells includes a charge storage layer and a control gate and is capable of holding two or more levels of data. The bit line is capable of transferring data to the memory cells in a one-to-one correspondence. The voltage generator carries out a verify operation by applying a verify voltage to the memory cells after performing first writing by applying a first voltage and then a second voltage lower than the first voltage to the control gate.

Nonvolatile semiconductor memory device which transfers a plurality of voltages to memory cells and method of writing the same

According to one embodiment, a system includes a memory, a controller which controls an operation of the memory in a data program, and data bus which connects the memory to the controller. The memory comprises a memory cell array with memory cells which have a bit assignment to 2(x is an integer number of 3 or more) threshold distributions, each memory cell storing x bits, and a control circuit which controls the data program of x bits to the memory cells. The controller comprises a first step generating y bit (y is an integer number and y&#x3c;x) based on x bits, transferring y bit to the memory, and generating 2threshold distributions based on y bit in the memory, and a second step executing after the first step, transferring x bits to the memory, and generating the 2threshold distributions based on x bits in the memory.

Multilevel nonvolatile semiconductor memory system

According to one embodiment, a nonvolatile semiconductor memory device includes memory cells storing data in a nonvolatile manner, word lines connected to the memory cells and including a first word line and a second word line which is n-th (n is an integer of 1 or more) from the first word line, and a control circuit configured to control a voltage of a word line to write data to a memory cell so that data are written in order from the first word line to the second word line. In a write sequence of the first word line, the control circuit applies a writing voltage to the second word line before writing a memory cell connected to the first word line.

According to one embodiment, a semiconductor memory device includes a memory cell array, a column decoder, and a control circuit configured to control the memory cell array and the column decoder. The control circuit is configured to load program data from outside, to execute a first data program in a first even-numbered bit line, to execute a second data program in a first odd-numbered bit line, to execute a verify read of the programmed bit lines, to determine whether a value of the verify read is programmed up to a predetermined threshold value, and to change, in a case where the value of the verify read fails to be programmed to the predetermined threshold value, an order of the first and second data programs, to execute the second data program in the first odd-numbered bit line, and then to execute the first data program in the first even-numbered bit line.

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Yokohama, Japan

Mitsuaki Honma