Patents by Inventor Toshimi Ikeda
Toshimi Ikeda has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 7307885Abstract: A nonvolatile semiconductor memory device includes a plurality of memory cells holding memory cell information, a plurality of bit lines connected to the plurality of memory cells, the plurality of bit lines including a first bit line conected to a selected one of the plurality of memory cells and a plurality of second bit lines connected to non-selected memory cells, a plurality of reference cells supplying different reference currents respectively, and a read-out circuit, wherein, when reading the memory cell information, the read-out circuit is coupled to the first bit line connected to the selected memory cell and coupled to one of the plurality of reference cells through one of the plurality of second bit lines connected to the non-selected memory cells.Type: GrantFiled: February 24, 2005Date of Patent: December 11, 2007Assignee: Fujitsu LimitedInventors: Toshimi Ikeda, Atsushi Hatakeyama, Nobutaka Taniguchi, Akira Kikutake, Kuninori Kawabata, Atsushi Takeuchi
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Patent number: 7281155Abstract: A semiconductor memory device having a shift redundancy function includes a switch circuit for changeably connecting a plurality of decode signal lines decoding an address signal to a plurality of selecting lines and redundancy selecting lines, and executes a switch operation for shifting at least one of a plurality of decode lines in the direction of a first redundancy selecting line positioned at one of the ends among a plurality of selecting lines or a second switch operation for shifting at least one of the decode lines in the direction of a second redundancy selecting line positioned at the other end among the selecting lines or both of the first and second operations when any fault occurs in a plurality of selecting lines.Type: GrantFiled: July 22, 1999Date of Patent: October 9, 2007Assignee: Fujitsu LimitedInventors: Satoshi Eto, Masato Matsumiya, Toshimi Ikeda, Yuki Ishii, Akira Kikutake, Kuninori Kawabata
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Patent number: 7184296Abstract: A memory device has a data line (DATA-BUS) for connection to a memory cell, a reference line (Reference-BUS) for reference, a precharge circuit (101), a load circuit (102), and an amplifier circuit (103). The precharge circuit is connected to the data line and the reference line and configured to precharge the data line and the reference line. The load circuit is connected to the data line and the reference line and configured to apply a first constant current to the data line and apply a second constant current which is smaller than the first constant current to the reference line. The amplification circuit is connected to the data line and the reference line and configured to amplify a differential voltage between the data line and the reference line.Type: GrantFiled: March 3, 2005Date of Patent: February 27, 2007Assignee: Fujitsu LimitedInventors: Atsushi Hatakeyama, Toshimi Ikeda, Nobutaka Taniguchi, Akira Kikutake, Kuninori Kawabata, Atsushi Takeuchi
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Patent number: 7064589Abstract: A semiconductor device which is driven by a first potential, a second potential lower than the first potential, and a third potential lower than the second potential includes a first Pch transistor and a first Nch transistor connected in series between the first potential and the third potential, a second Pch transistor having a drain node thereof connected to a gate node of the first Nch transistor, and a second Nch transistor having a source node thereof connected to a source node of the second Pch transistor, wherein the drain node and gate node of the second Nch transistor are fixed to the second potential and the first potential, respectively.Type: GrantFiled: March 10, 2005Date of Patent: June 20, 2006Assignee: Fujitsu LimitedInventors: Toshimi Ikeda, Kuninori Kawabata, Shuzo Otsuka
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Publication number: 20050185465Abstract: A memory device includes plural banks (BNKA, BNKB, BNKC, and BNKD), and each of the banks includes a plural memory cells storing data and plural bit lines reading data from the plural memory cells. Bit line lengths of all of the plural banks are equal.Type: ApplicationFiled: April 21, 2005Publication date: August 25, 2005Inventors: Nobutaka Taniguchi, Atsushi Hatakeyama, Toshimi Ikeda, Akira Kikutake, Kuninori Kawabata, Atsushi Takeuchi
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Publication number: 20050162955Abstract: A nonvolatile semiconductor memory device comprises a memory cell array in which memory cells each holding memory cell information are arrayed, reference cells which supply different reference currents respectively, and a read-out circuit. When reading the memory cell information from a selected one of the memory cells, the read-out circuit is brought into conduction to a first global bit line which is connected to a bit line of the selected memory cell, and brought into conduction to one of a plurality of second global bit lines respectively which are provided near the first global bit line and connected to bit lines of non-selected memory cells but not connected to the bit line of the selected memory cell, so that the memory cell information is determined by comparing a read-out current from the selected memory cell with each of the reference currents from the reference cells.Type: ApplicationFiled: February 24, 2005Publication date: July 28, 2005Inventors: Toshimi Ikeda, Atsushi Hatakeyama, Nobutaka Taniguchi, Akira Kikutake, Kuninori Kawabata, Atsushi Takeuchi
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Publication number: 20050152207Abstract: A semiconductor device which is driven by a first potential, a second potential lower than the first potential, and a third potential lower than the second potential includes a first Pch transistor and a first Nch transistor connected in series between the first potential and the third potential, a second Pch transistor having a drain node thereof connected to a gate node of the first Nch transistor, and a second Nch transistor having a source node thereof connected to a source node of the second Pch transistor, wherein the drain node and gate node of the second Nch transistor are fixed to the second potential and the first potential, respectively.Type: ApplicationFiled: March 10, 2005Publication date: July 14, 2005Inventors: Toshimi Ikeda, Kuninori Kawabata, Shuzo Otsuka
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Publication number: 20050141306Abstract: A memory device has a data line (DATA-BUS) for connection to a memory cell, a reference line (Reference-BUS) for reference, a precharge circuit (101), a load circuit (102), and an amplifier circuit (103). The precharge circuit is connected to the data line and the reference line and configured to precharge the data line and the reference line. The load circuit is connected to the data line and the reference line and configured to apply a first constant current to the data line and apply a second constant current which is smaller than the first constant current to the reference line. The amplification circuit is connected to the data line and the reference line and configured to amplify a differential voltage between the data line and the reference line.Type: ApplicationFiled: March 3, 2005Publication date: June 30, 2005Inventors: Atsushi Hatakeyama, Toshimi Ikeda, Nobutaka Taniguchi, Akira Kikutake, Kuninori Kawabata, Atsushi Takeuchi
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Patent number: 6847579Abstract: A semiconductor memory device includes a memory cell array having a plurality of memory cells. The memory cells are arranged at intersections between a plurality of word lines and a plurality of bit lines. The semiconductor memory device also includes a row decoder section located adjacent to the memory cell array. The row decoder section has a plurality of decoder circuits which selectively drive the word lines. The semiconductor memory device further includes a control circuit section located adjacent to the row decoder section. The control circuit section has at least one control circuit whose part is arranged in the row decoder section.Type: GrantFiled: April 29, 2002Date of Patent: January 25, 2005Assignees: Kabushiki Kaisha Toshiba, Fujitsu LimitedInventors: Fumihiro Kohno, Toshimi Ikeda
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Patent number: 6754122Abstract: After data readout, in equalizing a complementary pair of bit lines one of which has been overdriven with an overdrive voltage, excessive charges on the overdriven bit line are discharged by a discharge circuit. By adjusting the discharge period of the discharge circuit, the potential to which the bit lines are equalized is adjusted.Type: GrantFiled: February 5, 2003Date of Patent: June 22, 2004Assignees: Kabushiki Kaisha Toshiba, Fujitsu LimitedInventors: Masaharu Wada, Kenji Tsuchida, Tsuneo Inaba, Toshimi Ikeda
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Patent number: 6650590Abstract: One (first level shift circuit) of first and second level shift circuits is provided in a local word-drive-line driving circuit located near memory cell arrays. The second level shift circuit is provided in a global word-drive-line driving circuit located remote from the memory cell arrays.Type: GrantFiled: March 22, 2002Date of Patent: November 18, 2003Assignees: Kabushiki Kaisha Toshiba, Fujitsu LimitedInventors: Tsuneo Inaba, Fumihiro Kohno, Kenji Tsuchida, Toshimi Ikeda
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Publication number: 20030174545Abstract: After data readout, in equalizing a complementary pair of bit lines one of which has been overdriven with an overdrive voltage, excessive charges on the overdriven bit line are discharged by a discharge circuit. By adjusting the discharge period of the discharge circuit, the potential to which the bit lines are equalized is adjusted.Type: ApplicationFiled: February 5, 2003Publication date: September 18, 2003Applicant: Kabushiki Kaisha ToshibaInventors: Masaharu Wada, Kenji Tsuchida, Tsuneo Inaba, Toshimi Ikeda
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Publication number: 20030048688Abstract: A semiconductor memory device includes a memory cell array having a plurality of memory cells. The memory cells are arranged at intersections between a plurality of word lines and a plurality of bit lines. The semiconductor memory device also includes a row decoder section located adjacent to the memory cell array. The row decoder section has a plurality of decoder circuits which selectively drive the word lines. The semiconductor memory device further includes a control circuit section located adjacent to the row decoder section. The control circuit section has at least one control circuit whose part is arranged in the row decoder section.Type: ApplicationFiled: April 29, 2002Publication date: March 13, 2003Inventors: Fumihiro Kohno, Toshimi Ikeda
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Patent number: 6522003Abstract: A semiconductor device characterized by comprising a first insulating film formed on the semiconductor substrate, a first wiring or mark formed on the first insulating film, an electrically isolated pattern formed under the first insulating film and below the first wiring or mark, a hole formed in the first insulating film to connect the first wiring or mark and the electrically isolated pattern, and a second insulating film for covering the first wiring or mark.Type: GrantFiled: December 28, 1999Date of Patent: February 18, 2003Assignee: Fujitsu LimitedInventors: Takayoshi Minami, Osamu Tsuboi, Toshimi Ikeda, Masato Matsumiya, Kuninori Kawabata
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Publication number: 20020141277Abstract: One (first level shift circuit) of first and second level shift circuits is provided in a local word-drive-line driving circuit located near memory cell arrays. The second level shift circuit is provided in a global word-drive-line driving circuit located remote from the memory cell arrays.Type: ApplicationFiled: March 22, 2002Publication date: October 3, 2002Applicant: Kabushiki Kaisha ToshibaInventors: Tsuneo Inaba, Fumihiro Kohno, Kenji Tsuchida, Toshimi Ikeda
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Patent number: 6452860Abstract: A semiconductor memory device has a segment type word line structure and comprises a plurality of main word lines and a plurality of sub word lines which are arranged at different levels. The semiconductor memory device is provided with a memory cell array divided into a plurality of cell array blocks. A plurality of sub row decoder areas, each for selecting one of the sub word lines, are defined between the cell array blocks. A plurality of first metal wiring lines formed by use of the same wiring layer as the main word lines are provided. The first metal wiring lines pass across the sub row decoder areas and the cell array blocks.Type: GrantFiled: June 4, 2001Date of Patent: September 17, 2002Assignees: Kabushiki Kaisha Toshiba, Fujitsu LimitedInventors: Masaharu Wada, Kenji Tsuchida, Tsuneo Inaba, Atsushi Takeuchi, Toshimi Ikeda, Kuninori Kawabata
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Patent number: 6383447Abstract: An intermediary die 10 is provided with inner circumferential helical teeth r, a lower punch 7 is provided with outer circumferential helical teeth p, and an upper punch 8 is provided with outer circumferential helical teeth q, respectively. When the intermediary die 10, the lower punch 7 and the upper punch 8 all engage to manufacture helical gears by compacting powdered materials, lateral displacement (phase displacement) of a phase guide 11 which is adapted to engage with the upper outer punch 8a, is forcibly corrected to allow it to return to its original position, from the time when the load of the upper outer punch 8a is reduced to when the intermediary die 10 is released. There is also provided an escape surface on the pressing surface of the upper outer punch 8a. The escape surface is designed to reduce the slide contact force developed on a compacted product Ga when the upper outer punch 8a and the compacted product Ga are respectively displaced in a lateral direction.Type: GrantFiled: July 5, 2000Date of Patent: May 7, 2002Assignee: Honda Giken Kogyo Kabushiki KaishaInventors: Toyoshige Nakata, Tadaaki Shimada, Tatsuhiro Iio, Toshimasa Fujita, Toshimi Ikeda
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Publication number: 20010048631Abstract: A semiconductor memory device has a segment type word line structure and comprises a plurality of main word lines and a plurality of sub word lines which are arranged at different levels. The semiconductor memory device is provided with a memory cell array divided into a plurality of cell array blocks. A plurality of sub row decoder areas, each for selecting one of the sub word lines, are defined between the cell array blocks. A plurality of first metal wiring lines formed by use of the same wiring layer as the main word lines are provided. The first metal wiring lines pass across the sub row decoder areas and the cell array blocks.Type: ApplicationFiled: June 4, 2001Publication date: December 6, 2001Inventors: Masaharu Wada, Kenji Tsuchida, Tsuneo Inaba, Atsushi Takeuchi, Toshimi Ikeda, Kuninori Kawabata
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Patent number: 6317353Abstract: A power supply line is formed over a memory cell array which has arranged a plurality of memory cells using a metal wiring layer M1 which is disposed on the side closest to the memory cell array, of all the metal wiring layers. The power supply lines are formed over the memory cell array using not only an upper metal wiring layer M2 but the metal wiring layer M1 so that the wiring resistance of the power supply lines may decrease and a sufficient amount of current can be supplied to the power supply lines. Consequently, the circuits supplied with an electric current through the power supply lines become capable of high-speed operation. This is particularly effective for the high-speed operation of the circuits arranged around the memory cell array. The power supply line formed using the lower metal wiring layer M1 is connected over the memory cell array to a power supply line which is formed using the metal wiring layer M2 on the upper layer than the metal wiring layer M1.Type: GrantFiled: March 28, 2000Date of Patent: November 13, 2001Assignee: Fujitsu LimitedInventors: Toshimi Ikeda, Masato Matsumiya, Masato Takita
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Patent number: 6251743Abstract: Microstructures, including a plurality of spaced structural members which are bendable under an external force, undergo a treating method using a first treating liquid, to prevent permanent deformation, by removing the microstructure from the first treating liquid to an environment having a pressure less than atmospheric pressure; or moving the microstructure from the first treating liquid to a second treating liquid having a smaller surface tension than the first treating liquid, and then removing the microstructure from the second liquid; or drying the microstructure removed from the first treating liquid by exposing same to a liquid vapor having a smaller surface tension than the first treating liquid; or removing the microstructure from the first treating liquid to the atmosphere, and drying the microstructure using an energy beam of high intensity or an ultrasonic wave.Type: GrantFiled: May 5, 1998Date of Patent: June 26, 2001Assignees: Fujitsu Limited, Fujitsu VLSI LimitedInventors: Motoo Nakano, Hiroshi Nomura, Masaya Katayama, Toshimi Ikeda, Fumihiko Inoue, Junichi Ishikawa, Masahiro Kuwamura