Patents by Inventor Ayuka Tada

Ayuka Tada 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).

  • Publication number: 20200234760
    Abstract: In order to eliminate an increase in the source potential of a transistor selected during writing or reading, this semiconductor device is equipped with: a variable-resistance type first switch having a first terminal and a second terminal; a variable-resistance type second switch having a third terminal and a fourth terminal, the third terminal being connected to the second terminal to form an intermediate node; first wiring connected to the first terminal; second wiring connected to the fourth terminal and, in a planar view, extending in a direction crossing the first wiring; a first selection transistor connected to the first wiring; a second selection transistor connected to the second wiring; a first well terminal connection line to which a well terminal of the first selection transistor is connected; and a second well terminal connection line to which a well terminal of the second selection transistor is connected.
    Type: Application
    Filed: February 28, 2018
    Publication date: July 23, 2020
    Applicant: NEC CORPORATION
    Inventors: Makoto MIYAMURA, Yukihide TSUJI, Toshitsugu SAKAMOTO, Ryusuke NEBASHI, Ayuka TADA, Xu BAI
  • Patent number: 10720925
    Abstract: Provided is an integrated circuit that has reduced power consumption. The integrated circuit is provided with: a plurality of first wires one end of each of which is used as an input terminal; a plurality of second wires one end of each of which is used as an output terminal and which are respectively connected to the first wires; a bias wire which is connected to each of the second wires, and which is connected to a power supply or ground; a plurality of switches which connect the first wires or the bias wire and the second wires; and a selection circuit which selects electrical connection between the bias wire and the power supply or ground.
    Type: Grant
    Filed: September 11, 2017
    Date of Patent: July 21, 2020
    Assignee: NEC CORPORATION
    Inventors: Xu Bai, Toshitsugu Sakamoto, Yukihide Tsuji, Ayuka Tada, Makoto Miyamura, Ryusuke Nebashi
  • Publication number: 20200168275
    Abstract: A reconfigurable circuit comprising: a complementary resistive switch; a write circuit to configure the complementary resistive switch; a read circuit to get ON/OFF information of the complementary resistive switch; a register to store ON/OFF information of the complementary resistive switch.
    Type: Application
    Filed: May 12, 2017
    Publication date: May 28, 2020
    Applicant: NEC Corporation
    Inventors: Xu BAI, Toshitsugu SAKAMOTO, Yukihide TSUJI, Makoto MIYAMURA, Ayuka TADA, Ryusuke NEBASHI
  • Publication number: 20200145007
    Abstract: A reconfigurable circuit comprising: crossbar switches; wires, each of which is coupled to one output port of one crossbar switch and input ports of the other crossbar switches; at least one inverter inserted on each wire for driving long-distance signal transfer, wherein one or less first inverter is inserted on the wire between two adjacent crossbar switches; one or two second inverters inserted between a crossbar switch input port and its connected wire.
    Type: Application
    Filed: August 10, 2017
    Publication date: May 7, 2020
    Applicant: NEC Corporation
    Inventors: Xu BAI, Toshitsugu SAKAMOTO, Yukihide TSUJI, Makoto MIYAMURA, Ayuka TADA, Ryusuke NEBASHI
  • Publication number: 20200091914
    Abstract: A reconfigurable circuit includes: a plurality of first lines; one or more second lines; a non-volatile resistive cell coupling one of the first lines with one of the second lines at each cross-point between the first lines and the second lines; and first switch elements including first terminals respectively coupled to the first lines, wherein each of the first switch elements is separately turned on or off in accordance with a control signal applied thereto.
    Type: Application
    Filed: March 17, 2017
    Publication date: March 19, 2020
    Applicant: NEC CORPORATION
    Inventors: Xu BAI, Toshitsugu SAKAMOTO, Yukihide TSUJI, Makoto MIYAMURA, Ayuka TADA, Ryusuke NEBASHI
  • Patent number: 10396798
    Abstract: A reconfigurable circuit includes first and second wires and two or more paths active at different times. Each path includes: a first NVRS whose first terminal is connected to the first wire; a first transistor whose drain terminal is connected to a second terminal of the first NVRS; a second NVRS whose first terminal is connected to the second terminal of the first NVRS; a second transistor whose source terminal is connected to a second terminal of the second NVRS and whose drain terminal is connected to the second wire; and a 2-input AND circuit whose output is connected to a gate terminal of the first transistor. A time control signal is supplied to a first input of the 2-input AND circuit and a gate terminal of the second transistor. A write control signal is supplied to a second input of the 2-input AND circuit.
    Type: Grant
    Filed: October 16, 2015
    Date of Patent: August 27, 2019
    Assignee: NEC CORPORATION
    Inventors: Xu Bai, Toshitsugu Sakamoto, Munehiro Tada, Yukihide Tsuji, Ayuka Tada, Makoto Miyamura, Ryusuke Nebashi
  • Publication number: 20190253057
    Abstract: Provided is an integrated circuit that has reduced power consumption. The integrated circuit is provided with: a plurality of first wires one end of each of which is used as an input terminal; a plurality of second wires one end of each of which is used as an output terminal and which are respectively connected to the first wires; a bias wire which is connected to each of the second wires, and which is connected to a power supply or ground; a plurality of switches which connect the first wires or the bias wire and the second wires; and a selection circuit which selects electrical connection between the bias wire and the power supply or ground.
    Type: Application
    Filed: September 11, 2017
    Publication date: August 15, 2019
    Applicant: NEC CORPORATION
    Inventors: Xu BAI, Toshitsugu SAKAMOTO, Yukihide TSUJI, Ayuka TADA, Makoto MIYAMURA, Ryusuke NEBASHI
  • Publication number: 20190180818
    Abstract: In order to provide a highly reliable crossbar circuit that enables salvation of reversal of a resistive state of a variable resistance element, the semiconductor device has a configuration obtained by parallelly arranging two unit elements, each including variable-resistance two-terminal elements connected in series, the semiconductor device being provided with: a unit element group being connected to a first wiring and a second wiring; a first programming driver that changes, via the first wiring, a resistive state of the two-terminal element constituting the unit element group; a first selection transistor being connected to the first wiring and the first programming driver; a second programming driver that changes, via the second wiring, a resistive state of the two-terminal element constituting the unit element group; and a second selection transistor being connected to the second wiring and the second programming driver.
    Type: Application
    Filed: September 11, 2017
    Publication date: June 13, 2019
    Applicant: NEC Corporation
    Inventors: Makoto MIYAMURA, Ryusuke NEBASHI, Toshitsugu SAKAMOTO, Yukihide TSUJI, Xu BAI, Ayuka TADA
  • Patent number: 10305485
    Abstract: An object of the present invention is to provide a method for effectively performing characterization for circuit verification by static timing analysis, of a programmable logic integrated circuit including a crossbar switch including a resistance-variable element, and a logic circuit logically configured with the crossbar switch, wherein: the programmable logic integrated circuit is divided into a plurality of leaf cells including a plurality of load circuits including a part of the crossbar switch, and a power supply element input to the crossbar switch; the leaf cell is divided into delay paths each including a base leaf cell and a correction leaf cell; and circuit verification is performed based on a delay information library in which a delay time for the base leaf cell and a correction delay for the correction leaf cell are integrated into a delay time for the leaf cell.
    Type: Grant
    Filed: August 31, 2016
    Date of Patent: May 28, 2019
    Assignee: NEC CORPORATION
    Inventors: Ayuka Tada, Noboru Sakimura, Makoto Miyamura, Yukihide Tsuji, Ryusuke Nebashi, Xu Bai, Toshitsugu Sakamoto
  • Publication number: 20190052273
    Abstract: An object of the present invention is to provide a method for effectively performing characterization for circuit verification by static timing analysis, of a programmable logic integrated circuit including a crossbar switch including a resistance-variable element, and a logic circuit logically configured with the crossbar switch, wherein: the programmable logic integrated circuit is divided into a plurality of leaf cells including a plurality of load circuits including a part of the crossbar switch, and a power supply element input to the crossbar switch; the leaf cell is divided into delay paths each including a base leaf cell and a correction leaf cell; and circuit verification is performed based on a delay information library in which a delay time for the base leaf cell and a correction delay for the correction leaf cell are integrated into a delay time for the leaf cell.
    Type: Application
    Filed: August 31, 2016
    Publication date: February 14, 2019
    Applicant: NEC Corporation
    Inventors: Ayuka TADA, Noboru SAKIMURA, Makoto MIYAMURA, Yukihide TSUJI, Ryusuke NEBASHI, Xu BAI, Toshitsugu SAKAMOTO
  • Publication number: 20190028101
    Abstract: An object of the present invention is to provide a logic integrated circuit that increases reliability of configuration information held in a switch while maintaining high tamper resistance and a small chip area. The logic integrated circuit according to the present invention includes: a three-terminal resistance change switch including a first resistance change switch and a second resistance change switch connected in series; a reading circuit which reads first data based on a resistance state of the first resistance change switch and second data based on a resistance state of the second resistance change switch; and a first error detection circuit which compares the first data with the second data and issue an output based on a result of the comparison.
    Type: Application
    Filed: January 16, 2017
    Publication date: January 24, 2019
    Applicant: NEC Corporation
    Inventors: Ryusuke NEBASHI, Toshitsugu SAKAMOTO, Makoto MIYAMURA, Yukihide TSUJI, Ayuka TADA, Xu BAI
  • Publication number: 20190013811
    Abstract: The purpose of the present invention is to increase the efficiency with which silicon on a chip is used, and to easily reduce the size of a logic cell. To accomplish the purpose, this reconfigurable circuit includes: a logic memory unit configured from a resistance change element, and positioned distributed into at least two units; a logic unit for referencing the logic memory unit and performing logical operations; and a signal path switching unit for receiving the results of the logical operation of the logic unit and outputting said results to the outside. The logic memory part and the signal path switching part constitute part of a crossbar switching circuit, and share write wiring to the resistance change element.
    Type: Application
    Filed: January 18, 2017
    Publication date: January 10, 2019
    Applicant: NEC Corporation
    Inventors: Yukihide TSUJI, Toshitsugu SAKAMOTO, Makoto MIYAMURA, Xu BAI, Ayuka TADA, Ryusuke NEBASHI
  • Publication number: 20180302094
    Abstract: A reconfigurable circuit includes first and second wires and two or more paths active at different times. Each path includes: a first NVRS whose first terminal is connected to the first wire; a first transistor whose drain terminal is connected to a second terminal of the first NVRS; a second NVRS whose first terminal is connected to the second terminal of the first NVRS; a second transistor whose source terminal is connected to a second terminal of the second NVRS and whose drain terminal is connected to the second wire; and a 2-input AND circuit whose output is connected to a gate terminal of the first transistor. A time control signal is supplied to a first input of the 2-input AND circuit and a gate terminal of the second transistor. A write control signal is supplied to a second input of the 2-input AND circuit.
    Type: Application
    Filed: October 16, 2015
    Publication date: October 18, 2018
    Applicant: NEC Corporation
    Inventors: Xu BAI, Toshitsugu SAKAMOTO, Munehiro TADA, Yukihide TSUJI, Ayuka TADA, Makoto MIYAMURA, Ryusuke NEBASHI
  • Patent number: 10044355
    Abstract: A reconfigurable circuit comprising: a first level crossbar switch that has first non-volatile resistive switches; a second level crossbar switch that has second non-volatile resistive switches; and a first wire and third non-volatile resistive switches that are used for redundancy, wherein input wires of the second level crossbar switch are connected to output wires of the first level crossbar switch one-to-one, and input wires of the first level crossbar switch and output wires of the second level crossbar switch are connected to the first wire through the third non-volatile resistive switches.
    Type: Grant
    Filed: May 28, 2015
    Date of Patent: August 7, 2018
    Assignee: NEC CORPORATION
    Inventors: Xu Bai, Noboru Sakimura, Yukihide Tsuji, Ryusuke Nebashi, Ayuka Tada, Makoto Miyamura
  • Patent number: 10037789
    Abstract: In order to stably write data into a magnetic memory that uses in-plane current-induced perpendicular switching of magnetization to write data, the magnetic memory includes a recording layer formed as a perpendicular magnetization film, an adjacent layer joined to an upper surface or a lower surface of the recording layer, an external magnetic field application part configured to apply a first external magnetic field to the recording layer in a first direction which is an in-plane direction of the recording layer, and a current application part configured to allow a write current to flow through the adjacent layer in the first direction or a second direction which is opposite to the first direction. The external magnetic field application part is configured to switch a direction of a second external magnetic field applied in a direction perpendicular to the first direction in accordance with a direction of the write current.
    Type: Grant
    Filed: August 31, 2015
    Date of Patent: July 31, 2018
    Assignees: NEC CORPORATION, TOHOKU UNIVERSITY
    Inventors: Ryusuke Nebashi, Noboru Sakimura, Yukihide Tsuji, Ayuka Tada, Hideo Ohno
  • Publication number: 20180157779
    Abstract: Provided is a programmable logic integrated circuit wherein even if a failure occurs in any resistance-variable element, remedy would be possible and hence the improvement of reliability has been achieved. In a programmable logic integrated circuit comprising resistance-variable elements, when the states of the resistance-variable elements are to be changed according to externally inputted configuration information, a control means uses a reading means to read the states of the respective resistance-variable elements, and then uses a writing means to change only the states of resistance-changing elements that are different from a state indicated by the configuration information.
    Type: Application
    Filed: May 23, 2016
    Publication date: June 7, 2018
    Applicant: NEC Corporation
    Inventors: Noboru SAKIMURA, Yukihide TSUJI, Ayuka TADA, Xu BAI, Makoto MIYAMURA, Ryusuke NEBASHI
  • Publication number: 20180123595
    Abstract: A reconfigurable circuit comprising: a first level crossbar switch that has first non-volatile resistive switches; a second level crossbar switch that has second non-volatile resistive switches; and a first wire and third non-volatile resistive switches that are used for redundancy, wherein input wires of the second level crossbar switch are connected to output wires of the first level crossbar switch one-to-one, and input wires of the first level crossbar switch and output wires of the second level crossbar switch are connected to the first wire through the third non-volatile resistive switches.
    Type: Application
    Filed: May 28, 2015
    Publication date: May 3, 2018
    Applicant: NEC Corporation
    Inventors: Xu BAI, Noboru SAKIMURA, Yukihide TSUJI, Ryusuke NEBASHI, Ayuka TADA, Makoto MIYAMURA
  • Patent number: 9898070
    Abstract: A semiconductor integrated circuit (100) comprising: a plurality of processing circuits (11, 12, 13) each including a notification units for outputting a notification signal according to the processing state of the own processing circuit; a plurality of power supply switch units (SW1, SW2, SW3) for switching the connection states between the respective processing circuits and a power supply source; a power supply switch control circuit which is connected with the notification means (111, 121, 131), stores power supply control information (101) including a plurality of connection statuses, and controls the connection states on the basis of the notification signals and the power supply control information; and a data bus (BS) and the like connecting each of the processing circuits and the power supply switch control circuit, wherein: at least two or more of the plurality of processing circuits update the power supply control information via the data bus and the like before outputting a notification signal; and
    Type: Grant
    Filed: January 7, 2014
    Date of Patent: February 20, 2018
    Assignee: NEC CORPORATION
    Inventors: Yukihide Tsuji, Noboru Sakimura, Ryusuke Nebashi, Ayuka Tada
  • Publication number: 20170249981
    Abstract: In order to stably write data into a magnetic memory that uses in-plane current-induced perpendicular switching of magnetization to write data, the magnetic memory includes a recording layer formed as a perpendicular magnetization film, an adjacent layer joined to an upper surface or a lower surface of the recording layer, an external magnetic field application part configured to apply a first external magnetic field to the recording layer in a first direction which is an in-plane direction of the recording layer, and a current application part configured to allow a write current to flow through the adjacent layer in the first direction or a second direction which is opposite to the first direction. The external magnetic field application part is configured to switch a direction of a second external magnetic field applied in a direction perpendicular to the first direction in accordance with a direction of the write current.
    Type: Application
    Filed: August 31, 2015
    Publication date: August 31, 2017
    Applicants: NEC Corporation, TOHOKU UNIVERSITY
    Inventors: Ryusuke NEBASHI, Noboru SAKIMURA, Yukihide TSUJI, Ayuka TADA, Hideo OHNO
  • Patent number: 9692422
    Abstract: In a programmable logic integrated circuit, providing a spare circuit in preparation for the occurrence of a defective element results in a redundant circuit configuration. A programmable logic integrated circuit according to the present invention has: a plurality of logic blocks; a switch block for switching the connections between row and column wires by nonvolatile switch elements for switching; and a shifter block for connecting an input/output wire to said switch block. The shifter block includes a redundant wire and is equipped with nonvolatile switch elements for shifting that control the connections of the wires constituting said redundant wire and said row wires.
    Type: Grant
    Filed: February 27, 2015
    Date of Patent: June 27, 2017
    Assignee: NEC Corporation
    Inventors: Ryusuke Nebashi, Makoto Miyamura, Noboru Sakimura, Yukihide Tsuji, Ayuka Tada