Kabushiki Kaisha Toshiba

Toshiba Memory Corporation

Solid State System Co., Ltd.

Kioxia Corporation

Hitoshi Shiga

Shigeru Atsumi

Toru Tanzawa

Tadayuki Taura

Akira Umezawa

Yoshinori Takano

Tokumasa Hara

Masanobu Saito

Hironori Banba

Chih-Hung Wang

Chin Hsi Lin

Ken Takeuchi

Takuya Futatsuyama

Koji Kato

Koichi Kawai

Susumu Fujimura

Hidetaka Tsuji

Norihiro Fujita

Yasushi Kameda

Osamu Nagao

Ayako Yamano

Yoshihiko Shindo

Noboru Shibata

Masanobu Shirakawa

Hideo Kato

Naoya Tokiwa

Masahiro Yoshihara

Yasuhiko Honda

Koichi Fukuda

Hidetoshi Saito

Kan Shimizu

Kenji Sakurada

Masaki Fujiu

Toshihiko Himeno

Teruo Takagiwa

Kiyofumi Sakurai

Ryuichi Fujimoto

Shigehito Saigusa

Yoshihisa Kondo

Makoto Morimoto

Yumi Takada

Makoto Miakashi

Kenji Mima

Motoki Nagata

Chih-Chung Chen

Sheng-Lin Hung

Kouichirou Yamaguchi

A semiconductor storage device includes a memory string, a sense amplifier connected to the memory string, first, second, third, and fourth latch circuits that are each connected to the sense amplifier, a first wiring connected to the sense amplifier, the first latch circuit and the second latch circuit, a second wiring connected to the third latch circuit, a third wiring connected to the fourth latch circuit, a first switch transistor between the first wiring and the third wiring, a second switch transistor between the first wiring and the second wiring, and a third switch transistor between the second wiring and the third wiring.

Semiconductor storage device

A semiconductor memory device includes a block decoder having a sense node, and a control unit. The block decoder includes first and second transistors each connected between a first node and ground, a third transistor connected between a power source voltage and a second node, a fourth transistor connected between the first and second nodes and controlled by the same gate signal as the third transistor, a fifth transistor having a first terminal connected to the sense node and a gate connected to the second node through an inverter, and a latch circuit that switches the first transistor on and off according to its setting. The control unit determines the setting of the latch circuit, according to a logic level based on a voltage of the sense node during an operation in which the second and third transistors are turned off and the fourth transistor is turned on.

Semiconductor memory device that includes block decoders each having plural transistors and a latch circuit

Semiconductor memory device that includes a block decoder having plural transistors and a latch circuit

According to one embodiment, a semiconductor memory device includes: a word line; a first memory cell; a first circuit; and a second circuit. The first memory cell is connected to the word line. The first circuit generates a first voltage having a waveform including a first time period during which a voltage value increases with time and a second time period during which the voltage value decreases with time, and applies the generated first voltage to the word line. The second circuit measures first time from a first timing when a state of the first memory cell changes according to the first voltage to a second timing when the state of the first memory cell changes according to the first voltage after the first timing. The second circuit determines first data stored in the first memory cell on the basis of the measured first time.

Read process in a semiconductor memory device including a memory cell transistor

A memory system includes: a semiconductor memory device; and a controller capable of issuing a first read instruction and a second read instruction different from the first read instruction. When receiving the first read instruction, the semiconductor memory device reads first data and second data from a memory cell array, holds the first data and the second data in the latch circuit, and outputs the first data to the controller. When receiving the second read instruction, the semiconductor memory device outputs third data based on the second data held by the latch circuit to the controller. The controller performs soft decision processing using the third data.

Memory system

A semiconductor storage device has a memory cell array, a plurality of word lines, a plurality of bit lines, and a plurality of blocks including a group of at least some memory cells, a defect information storage block that stores defect information in the memory cell array, a first defect detection circuitry that reads data of at least some memory cells in the defect information storage block, verifies the data, and determines whether there is a defect in the defect information storage block, a second defect detection circuitry that changes a read voltage level for reading the data of the memory cells, rereads data of at least some memory cells in the defect information storage block, verifies the data, and determines whether there is the defect in the defect information storage block, and a defect determination circuitry that determines the defect information storage block as a defective block.

A nonvolatile semiconductor memory device includes a memory cell array and a control circuit. The memory cell array comprises a plurality of memory cells and stores initial setting data in the plurality of memory cells. The control circuit is configured to apply a first voltage to gates of the plurality of memory cells to read the initial setting data and, depending on that read result, apply a second voltage different from the first voltage to the gates of the plurality of memory cells to read the initial setting data.

Nonvolatile semiconductor memory device and read method thereof

A memory device includes a memory chip that stores data, and an external controller that controls the memory chip. The memory chip includes multiple memory cells configured to store data of two or more bits; and an internal controller that executes a program operation for page data including a lower and an upper page program operation, and executes a read operation for page data including a lower and an upper page read operation. The external controller includes an error correction unit that performs error correction encoding on data to be programmed into the memory cell array and performs error correction decoding on data. The internal controller outputs the read page data from the memory cell array to the external controller, regardless of whether the upper page program operation is complete or not, in the upper page read operation.

Memory device

According to one embodiment, a semiconductor memory device includes a plurality of blocks in a memory cell, each of the blocks acting as an erasure unit of data, the block including a plurality of pages, each of the pages including a plurality of memory cell transistors, each of the memory cell transistors being configured to be an erasure state or a first retention state based on a threshold voltage of the memory cell transistor, and a controller searching data in the block with respect to, writing a first flag denoting effective into a prescribed page of the block with the erasure state, and writing the first flag denoting non-effective into a prescribed page of the block with the first retention state, reading out the prescribed page of the block with the first retention state, and determining that the block is writable when the first flag denotes effective.

Semiconductor memory device and method for writing therein

According to one embodiment, a memory system includes a first nonvolatile semiconductor memory, a second nonvolatile semiconductor memory and a controller. The first memory has memory cells and executes a first operation that is at least one of write, read, and erase operations with respect to the memory cells. The first operation includes a first sub-operation and a second-sub operation that consume a current which is equal to or higher than a predetermined current. The second memory has memory cells and executes a second operation that is at least one of write, read, and erase operations with respect to the memory cells. The second operation includes a third sub-operation and a fourth sub-operation that consume a current which is equal to or higher than the predetermined current. The controller controls the first operation and the second operation of the first memory and the second memory.

Memory system having nonvolatile semiconductor memories with control operation having high-current and low-current periods

According to one embodiment, a semiconductor memory device includes a memory cell array, a first buffer, a second buffer, an interface unit and a controller. Data is transferred between the interface unit and the first buffer. The controller controls the first buffer, the second buffer and the interface unit. When receiving a first command and first data at a test time, the controller transfers the first data to the first buffer via the interface unit. When receiving a second command as a dummy command, the controller reads second data from the memory cell array to the second buffer and, at the same time, outputs first data held in the first buffer via the interface unit.

Semiconductor memory device capable of testing signal integrity

When performing a word line leak test to determine a leak state of the word lines, the control circuit applies, from the voltage control circuit to the word lines connected to the memory cell array written with test pattern data, voltages corresponding to the test pattern data. Thereafter, it switches the transfer transistors to a nonconductive state, thereby setting the word lines in a floating state. After a lapse of a certain time from switching of the transfer transistors to a nonconductive state, it activates the sense amplifier circuit to perform a read operation in the memory cell array. Then it compares a result of the read operation with an expectation value corresponding to the test pattern data.

Nonvolatile semiconductor memory device and method testing the same

A nonvolatile semiconductor memory device comprises: a memory cell array configured by a plurality of first and second lines and a plurality of memory cells, each of the memory cells being selected by the first and second lines and being configured to store multiple-bit data in a nonvolatile manner; a data bus configured to transmit write data to be written to the plurality of memory cells, the write data being configured by a plurality of unit data; a column selection unit configured by a plurality of data latches, each of the data latches being configured to directly receive the unit data inputted from the data bus and to retain the unit data; and a control unit configured to control activation/non-activation of the data latches. During a programming operation, for each unit data inputted to the column selection unit, the control unit activates one of the data latches corresponding to a certain one of the memory cells where the unit data is to be stored.

Nonvolatile semiconductor memory device

In writing operation, charge pumps of a memory apply any of first to n-th voltages which are different from each other. An application-voltage selector selects voltages to be applied to WLs among the first to n-th voltages. A word-line number register stores the number of WLs to which each of the first to n-th voltages is to be applied for the first to n-th voltages. A storage stores a correspondence table that stores a relationship between the number of WLs for each of the first to n-th voltages and the number of charge pumps allocated to the first to n-th voltages. A generation-voltage selector allocates charge pumps to generate the first to n-th voltages based on the correspondence table according to the number of WLs for each of the first to n-th voltages. Each charge pump generates any of the first to n-th voltages allocated by the generation-voltage selector.

Semiconductor memory device

A memory system with a semiconductor memory device, in which a physical block of n-bits serves as an erase unit, wherein the address management of the memory device is performed by a logical block with m-bits, 'm' being larger than 'n' and expressed by a power of two, and wherein a n-bit portion continued from the head address in the logical block is defined as a first management unit corresponding to one physical block of the memory device, and a number of the remaining fraction portions each defined as a second management unit are gathered so as to correspond to one physical block of the memory device.

Memory system with a semiconductor memory device

Growing community of inventors

Yokohama, Japan

Hitoshi Shiga