Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Matsushita Electronics Corporation

Shunichi Iwanari

Hirohito Kikukawa

Yasuo Murakuki

Hironori Akamatsu

Masashi Agata

Akihiro Sawada

Hisakazu Kotani

Yasushi Gohou

Toshio Yamada

Masahiko Sakagami

Hiroshige Hirano

Takashi Miki

Kunisato Yamaoka

Ichiro Nakao

Tetsuji Nakakuma

Yoshihisa Kato

Masanori Matsuura

Yoshiaki Nakao

Hiroyuki Yamauchi

Masahiro Nakanishi

Masayuki Toyama

Akinori Shibayama

Atsushi Fujiwara

Kazuhiro Matsuyama

The demand for reducing the size and increasing the degree of integration of semiconductor memory devices has increased. In a semiconductor memory device, a smoothing capacitor which has to be provided therein for stabilizing a power supply voltage etc. is formed in an underlying layer of memory cells A and B to overlap the two memory cells A and B which are adjacent each other. Thus, an area occupied by the smoothing capacitor having a large capacity can be reduced to increase the degree of integration, and the smoothing capacitor having a large capacity can be provided in the semiconductor memory device.

Semiconductor memory device

A semiconductor memory device includes a plurality of memory cells connected to a common bit line, a plurality of select lines each configured to select at least one of the memory cells, a plurality of drive circuits each configured to drive at least one of the select lines, a sense amplifier configured to amplify a voltage occurring at the bit line depending on data stored in the selected memory cell. A memory region where the memory cells are provided has a first region and a second region. When the first region is read, a larger number of the select lines are simultaneously driven by the corresponding common drive circuit than those in the second region, and a larger number of the memory cells are simultaneously selected than those in the second region.

Semiconductor memory device and semiconductor integrated circuit

A semiconductor memory device, including: a cell array block including a plurality of memory cells arranged therein; and a controller, wherein the controller controls the semiconductor memory device so that: an operation of reading out data from a second region in the cell array block is initiated before completion of an operation of outputting data read out from a first region in the cell array block; and the data read out from the second region is output successively after the completion of the operation of outputting data read out from the first region.

Semiconductor memory device and semiconductor device

A semiconductor memory device includes a plurality of memory cell arrays each including a plurality of memory cells arranged in a matrix pattern, and a plurality of cell plate lines each being shared by the memory cell arrays, each of the cell plate lines corresponding to each of rows of the memory cells and each of the cell plate lines being connected to the memory cells of a corresponding one of the rows. Each of the memory cell arrays includes a plurality of word lines each of which corresponds to each of the rows of the memory cells in the memory cell array. The number of the memory cells connected to each of the cell plate lines is larger than the number of the memory cells connected to one of the word lines corresponding to the each of the cell plate lines.

Semiconductor memory device and semiconductor memory system

Provided is a semiconductor memory device compatible with a SRAM and capable of a high-speed data transfer operation while maintaining data reliability. An access to a memory corestarts when an external chip enable signal XCE performs a falling transition. Simultaneously, an external write enable signal XWE and an external address signal ADD are received, and a memory cellin the memory corecorresponding to the received external address signal ADD is selected. When a data read-out from the memory cellor a data write-in to the memory cellis complete, a rewrite timeris activated in accordance with a rising transition of an external chip enable signal XCE or a rising transition of the external write enable signal XWE for performing a data rewrite for the memory cell

A ferroelectric memory provided in a memory system stores in advance set data for data write time to memory cells. The set data include two types of data that differ between in a power-on state and in a power-off instruction time. When power is turned on, the set data that are stored in the ferroelectric memory are stored and retained in a latch circuit by a control circuit. Based on the set data retained in the latch circuit, data writing is performed in the ferroelectric memory respectively in the power-on state and in the power-off instruction time. Thus, operations of the ferroelectric memory can be controlled with desired operation timings according to operating conditions for each memory system. Excessive stress application to the ferroelectric memory during the power-on state is prevented and endurance deterioration is suppressed, while data retention characteristics after power-off are improved.

Memory system and semiconductor integrated circuit

A memory system of the present invention includes a memory device having a nonvolatile memory and an access device which accesses the memory device. The memory device has a detection unit to detect a temperature of the memory device, a determination unit to determine an operating condition in accordance with the detected temperature and a notification unit to notify the access device of the determined operating condition. The access device has an interface unit to connect to the memory device and a controlling unit to control the interface unit in accordance with the notified operating condition from the memory device.

Memory system

A semiconductor storage apparatus comprising: a ferroelectric memory; an SRAM; a counter; a CAMthat judges whether or not a block of data requested to be read out from the ferroelectric memory is stored in the SRAM; a storage control unitthat, if a result of the judgment is negative, performs a control to read out the requested block of data from the ferroelectric memory and stores a copy of the read-out block of data into a unit storage area in the SRAMthat corresponds to the count value indicated by the counter; and a counter control unitthat causes the counterto update the count value each time a result of the judgment is negative.

Semiconductor storage apparatus

A ferroelectric memory provided in a memory system stores in advance set data for data write time to memory cells. The set data include two types of data that differ between in a power-on state and in a power-off instruction time, When power is turned on, the set data that are stored in the ferroelectric memory are stored and retained in a latch circuit by a control circuit. Based on the set data retained in the latch circuit, data writing is performed in the ferroelectric memory respectively in the power-on state and in the power-off instruction time. Thus, operations of the ferroelectric memory can be controlled with desired operation timings according to operating conditions for each memory system. Excessive stress application to the ferroelectric memory during the power-on state is prevented and endurance deterioration is suppressed, while data retention characteristics after power-off are improved.

A ferroelectric memory of the present invention comprises: a plurality of normal cells, each of which includes a first ferroelectric capacitor for holding data and a first transistor connected to a first electrode of the first ferroelectric capacitor; a first bit line connected to the first transistor; a first bit line precharge circuit which is a switch circuit provided between the first bit line and a ground; and a word line connected to a gate of the first transistor. The word line is deactivated to disconnect the first ferroelectric capacitor from the first bit line before the first bit line precharge circuit is driven to discharge a potential of the first bit line.

Ferroelectric memory and method for reading data from the ferroelectric memory

Provided is a semiconductor memory device compatible with a SRAM and capable of a high-speed data transfer operation while maintaining data reliability. An access to a memory corestarts when an external chip enable signal XCE performs a falling transition. Simultaneously, an external write enable signal XWE and an external address signal ADD are received, and a memory cell, in the memory core, corresponding to the received external address signal ADD is selected. When a data read-out from the memory cellor a data write-in to the memory cellis complete, a rewrite timeris activated in accordance with a rising transition of an external chip enable signal XCE or a rising transition of the external write enable signal XWE for performing a data rewrite for the memory cell

To provide a semiconductor storage device which can adapt to assembly processes involving different treatment temperatures, can become unrewritable when rewriting of data by the user is prohibited, negates the necessity for developing different semiconductor storage devices, and lowers development cost. A semiconductor storage device is provided with, as areas for storing faulty address information indicating a faulty area and operation mode setting information about the semiconductor storage device, a first setting function storage areaformed from electrically-rewritable nonvolatile memory and a second setting function storage areaformed from once-rewritable nonvolatile memory. Transfer of faulty address information to a faulty address registerand transfer of operation mode setting information to an operation mode registerare selectively performed.

Semiconductor storage device

A semiconductor memory device having a semiconductor substrate includes a plurality of reference cellsand a plurality of bit lines. The reference cellsare formed in a region near the centerline of a predetermined region of the semiconductor substrate which is perpendicular to the bit lines. The bit linesform pairs each composed of two adjacent bit lines. Two bit linesin each pair have a first parallel state and a second parallel state in which positions of the two bit lines are reversed from the first parallel state. Each pair of bit lineshas at least one cross sectionwhere one of the pair of bit linescrosses the other, to switch between the first parallel state and the second parallel state. The cross sectionis provided in the predetermined region of the semiconductor substrate such that the length of a bit linein the first parallel state is equal to the length of the bit linein the second parallel state. The semiconductor memory device is reduced in size.

Growing community of inventors

Kyoto, Japan

Shunichi Iwanari