Patents by Inventor Taku Ogura

Taku Ogura 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: 20080074925
    Abstract: A transistor is arranged for electrically isolating a sense amplifier formed of a thin film transistor from a data line electrically coupled to the sense amplifier. When a write driver drives the data line, a control signal is applied to isolate the data line from the sense amplifier.
    Type: Application
    Filed: November 8, 2007
    Publication date: March 27, 2008
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Taku Ogura, Tadaaki Yamauchi, Takashi Kubo
  • Patent number: 7339831
    Abstract: Until the number of pulse application n reaches 12, as a first-half pulse, a pulse is set to have a width fixed to 2 ms, and its voltage is increased every time. As a latter-half pulse, the pulse is set to have a width fixed to 3 ms and the pulse voltage is increased every time until the maximum voltage is attained. After the maximum voltage is attained, first, the pulse of a width of 3 ms is applied twice, the pulse of a width of 4 ms with the maximum voltage is applied twice, and the pulse of a width of 5 ms with the maximum voltage is applied twice. Even after the maximum voltage is attained, change over time of a threshold voltage can be more linear. Thus, a non-volatile semiconductor memory device allowing efficient programming operation and erasing operation in a short period of time can be provided.
    Type: Grant
    Filed: May 22, 2007
    Date of Patent: March 4, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Hidenori Mitani, Fumihiko Nitta, Tadaaki Yamauchi, Taku Ogura
  • Publication number: 20080019162
    Abstract: This non-volatile semiconductor storage device includes a flip-flop in which two inverters, each consisting of a load transistor and a storage transistor connected in series, are cross-connected; and two gate transistors, each respectively connected to a node of the flip-flop on a side thereof. The storage transistors of the inverters are constituted by storage transistors which can be threshold voltage controlled by injection of electrons into the neighborhood of their gates. This non-volatile semiconductor storage device further includes two bit lines, each of which is connected to a respective one of the two gate transistors; a word line which is connected to both of the gate electrodes of the two gate transistors; a first voltage supply line which is connected to the sources of the storage transistors of the inverters; and a second voltage supply line which is connected to the sources of the load transistors of the inverters.
    Type: Application
    Filed: June 5, 2007
    Publication date: January 24, 2008
    Inventors: Taku OGURA, Masaaki Mihara, Yoshiki Kawajiri
  • Publication number: 20080019184
    Abstract: A multi-level semiconductor memory device for storing multi-level data having three or more values is implemented by utilizing a nonvolatile memory device for storing 2-valued data. Identification of successive 16-bit data externally applied is performed with external address bit AA [2], and a storage block is selected with external address bit AA [23]. Upper word data LW and lower word data UW are compressed into byte data of 8 bits, respectively, and stored in a memory cell array.
    Type: Application
    Filed: August 20, 2007
    Publication date: January 24, 2008
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Hidenori Mitani, Tadaaki Yamauchi, Taku Ogura
  • Publication number: 20070297251
    Abstract: A memory array including memory mats is arranged in a U shape when seen in two dimensions, and a logic circuit and an analog circuit are arranged in a region unoccupied by the memory array. This facilitates transmission of power supply voltage and signals between the peripheral circuit including the analog and logic circuits and the pad band including power supply and data pads. The analog circuit is positioned close to the power supply pad, so that voltage drop due to the resistance of power supply interconnection is restricted. It is also possible to separate a charge pumping power supply interconnection and a peripheral circuit power supply interconnection in the vicinity of the power supply pad.
    Type: Application
    Filed: June 26, 2007
    Publication date: December 27, 2007
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Taku Ogura, Tadaaki Yamauchi, Hidenori Mitani, Takashi Kubo, Kengo Aritomi
  • Publication number: 20070285146
    Abstract: In the present semiconductor device a positive, driving pump circuit is driven by an external power supply potential EXVDD (for example of 1.8V) to generate a positive voltage VPC (for example of 2.4V). A negative pump circuit for internal operation is driven by the positive voltage VPC to generate a negative voltage VNA (for example of ?9.2V) required in an erasure or similar internal operation for a word line. The negative pump circuit for internal operation can have a smaller number of stages of pump and hence consume a smaller area than when the circuit is driven by the external power supply voltage EXVDD (for example of 1.8V) as conventional.
    Type: Application
    Filed: July 3, 2007
    Publication date: December 13, 2007
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Minoru Senda, Kiyohiro Furutani, Taku Ogura, Shigehiro Kuge, Satoshi Kawasaki, Tadaaki Yamauchi
  • Publication number: 20070285987
    Abstract: Until the number of pulse application n reaches 12, as a first-half pulse, a pulse is set to have a width fixed to 2 ms, and its voltage is increased every time. As a latter-half pulse, the pulse is set to have a width fixed to 3 ms and the pulse voltage is increased every time until the maximum voltage is attained. After the maximum voltage is attained, first, the pulse of a width of 3 ms is applied twice, the pulse of a width of 4 ms with the maximum voltage is applied twice, and the pulse of a width of 5 ms with the maximum voltage is applied twice. Even after the maximum voltage is attained, change over time of a threshold voltage can be more linear. Thus, a non-volatile semiconductor memory device allowing efficient programming operation and erasing operation in a short period of time can be provided.
    Type: Application
    Filed: May 22, 2007
    Publication date: December 13, 2007
    Applicant: Renesas Technology Corp.
    Inventors: Hidenori Mitani, Fumihiko Nitta, Tadaaki Yamauchi, Taku Ogura
  • Patent number: 7307886
    Abstract: A transistor is arranged for electrically isolating a sense amplifier formed of a thin film transistor from a data line electrically coupled to the sense amplifier. When a write driver drives the data line, a control signal is applied to isolate the data line from the sense amplifier.
    Type: Grant
    Filed: July 7, 2006
    Date of Patent: December 11, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Taku Ogura, Tadaaki Yamauchi, Takashi Kubo
  • Patent number: 7268612
    Abstract: In the present semiconductor device a positive, driving pump circuit is driven by an external power supply potential EXVDD (for example of 1.8V) to generate a positive voltage VPC (for example of 2.4V). A negative pump circuit for internal operation is driven by the positive voltage VPC to generate a negative voltage VNA (for example of ?9.2V) required in an erasure or similar internal operation for a word line. The negative pump circuit for internal operation can have a smaller number of stages of pump and hence consume a smaller area than when the circuit is driven by the external power supply voltage EXVDD (for example of 1.8V) as conventional.
    Type: Grant
    Filed: January 30, 2007
    Date of Patent: September 11, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Minoru Senda, Kiyohiro Furutani, Taku Ogura, Shigehiro Kuge, Satoshi Kawasaki, Tadaaki Yamauchi
  • Patent number: 7248513
    Abstract: A memory array including memory mats is arranged in a U shape when seen in two dimensions, and a logic circuit and an analog circuit are arranged in a region unoccupied by the memory array. This facilitates transmission of power supply voltage and signals between the peripheral circuit including the analog and logic circuits and the pad band including power supply and data pads. The analog circuit is positioned close to the power supply pad, so that voltage drop due to the resistance of power supply interconnection is restricted. It is also possible to separate a charge pumping power supply interconnection and a peripheral circuit power supply interconnection in the vicinity of the power supply pad.
    Type: Grant
    Filed: September 15, 2004
    Date of Patent: July 24, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Taku Ogura, Tadaaki Yamauchi, Hidenori Mitani, Takashi Kubo, Kengo Aritomi
  • Patent number: 7230852
    Abstract: Until the number of pulse application n reaches 12, as a first-half pulse, a pulse is set to have a width fixed to 2 ms, and its voltage is increased every time. As a latter-half pulse, the pulse is set to have a width fixed to 3 ms and the pulse voltage is increased every time until the maximum voltage is attained. After the maximum voltage is attained, first, the pulse of a width of 3 ms is applied twice, the pulse of a width of 4 ms with the maximum voltage is applied twice, and the pulse of a width of 5 ms with the maximum voltage is applied twice. Even after the maximum voltage is attained, change over time of a threshold voltage can be more linear. Thus, a non-volatile semiconductor memory device allowing efficient programming operation and erasing operation in a short period of time can be provided.
    Type: Grant
    Filed: September 15, 2004
    Date of Patent: June 12, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Hidenori Mitani, Fumihiko Nitta, Tadaaki Yamauchi, Taku Ogura
  • Publication number: 20070120592
    Abstract: In the present semiconductor device a positive, driving pump circuit is driven by an external power supply potential EXVDD (for example of 1.8V) to generate a positive voltage VPC (for example of 2.4V). A negative pump circuit for internal operation is driven by the positive voltage VPC to generate a negative voltage VNA (for example of ?9.2V) required in an erasure or similar internal operation for a word line. The negative pump circuit for internal operation can have a smaller number of stages of pump and hence consume a smaller area than when the circuit is driven by the external power supply voltage EXVDD (for example of 1.8V) as conventional.
    Type: Application
    Filed: January 30, 2007
    Publication date: May 31, 2007
    Applicant: Renesas Technology Corp.
    Inventors: Minoru Senda, Kiyohiro Furutani, Taku Ogura, Shigehiro Kuge, Satoshi Kawasaki, Tadaaki Yamauchi
  • Publication number: 20070097774
    Abstract: A multi-level semiconductor memory device for storing multi-level data having three or more values is implemented by utilizing a nonvolatile memory device for storing 2-valued data. Identification of successive 16-bit data externally applied is performed with external address bit AA [2], and a storage block is selected with external address bit AA [23]. Upper word data LW and lower word data UW are compressed into byte data of 8 bits, respectively, and stored in a memory cell array.
    Type: Application
    Filed: December 15, 2006
    Publication date: May 3, 2007
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Hidenori Mitani, Tadaaki Yamayuchi, Taku Ogura
  • Patent number: 7180362
    Abstract: In the present semiconductor device a positive, driving pump circuit is driven by an external power supply potential EXVDD (for example of 1.8V) to generate a positive voltage VPC (for example of 2.4V). A negative pump circuit for internal operation is driven by the positive voltage VPC to generate a negative voltage VNA (for example of ?9.2V) required in an erasure or similar internal operation for a word line. The negative pump circuit for internal operation can have a smaller number of stages of pump and hence consume a smaller area than when the circuit is driven by the external power supply voltage EXVDD (for example of 1.8V) as conventional.
    Type: Grant
    Filed: September 15, 2004
    Date of Patent: February 20, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Minoru Senda, Kiyohiro Furutani, Taku Ogura, Shigehiro Kuge, Satoshi Kawasaki, Tadaaki Yamauchi
  • Publication number: 20070036001
    Abstract: After data writing is performed by injecting electrons into a floating gate from a semiconductor substrate of a memory cell, the gate voltage is set at ?3 V, and the source voltage, the drain voltage and the substrate voltage are set at 0 V, thereby detrapping the electrons trapped in an oxide film during data writing. The gate voltage (?3 V) is set at a negative voltage value that is smaller in absolute value than the gate voltage (?10.5 V) applied during data erasing.
    Type: Application
    Filed: July 27, 2006
    Publication date: February 15, 2007
    Inventors: Akihiko Kanda, Taku Ogura, Makoto Muneyasu
  • Publication number: 20070014162
    Abstract: A transistor is arranged for electrically isolating a sense amplifier formed of a thin film transistor from a data line electrically coupled to the sense amplifier. When a write driver drives the data line, a control signal is applied to isolate the data line from the sense amplifier.
    Type: Application
    Filed: July 7, 2006
    Publication date: January 18, 2007
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Taku Ogura, Tadaaki Yamauchi, Takashi Kubo
  • Patent number: 7164601
    Abstract: A multi-level semiconductor memory device for storing multi-level data having three or more values is implemented by utilizing a nonvolatile memory device for storing 2-valued data. Identification of successive 16-bit data externally applied is performed with external address bit AA [2], and a storage block is selected with external address bit AA [23]. Upper word data LW and lower word data UW are compressed into byte data of 8 bits, respectively, and stored in a memory cell array.
    Type: Grant
    Filed: September 9, 2004
    Date of Patent: January 16, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Hidenori Mitani, Tadaaki Yamauchi, Taku Ogura
  • Patent number: 7164602
    Abstract: The PROM area is adjacent to the normal memory cell area. The data writing (normal writing) and the data reading (normal reading) for normal memory cell areas and the data writing (redundant writing) for the PROM area are carried out from the side of the normal memory cell areas. The data reading (redundant reading) for the PROM area is carried out from the side of the PROM area. In the PROM area, the PROM cells having the same structure as that of the normal memory cells are connected to the redundant sub bit lines. In the redundant writing, in the select gate area, the redundant sub bit lines and main bit lines are connected. In the redundant reading, in the redundant gate area having the same layout as that of the select gate area, the redundant sub bit lines are connected to redundant bit lines.
    Type: Grant
    Filed: September 15, 2004
    Date of Patent: January 16, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Takeshi Hamamoto, Hidenori Mitani, Taku Ogura
  • Patent number: 7149115
    Abstract: A transistor is arranged for electrically isolating a sense amplifier formed of a thin film transistor from a data line electrically coupled to the sense amplifier. When a write driver drives the data line, a control signal is applied to isolate the data line from the sense amplifier.
    Type: Grant
    Filed: September 15, 2004
    Date of Patent: December 12, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Taku Ogura, Tadaaki Yamauchi, Takashi Kubo
  • Publication number: 20050213387
    Abstract: An internal voltage generating circuit generates and supplies a boosted voltage higher than an internal power supply voltage, as an operating power supply voltage, to a sense amplifier in a read circuit for reading data of a memory cell. A bit line precharge current supplied via an internal data line is produced from the internal power supply voltage. It is possible to provide a nonvolatile semiconductor memory device, which can perform a precise sense operation and an accurate reading of data even under a low power supply voltage condition.
    Type: Application
    Filed: March 18, 2005
    Publication date: September 29, 2005
    Inventors: Takashi Kubo, Takashi Itoh, Yasuhiro Kashiwazaki, Taku Ogura, Kiyohiro Furutani