Patents by Inventor Makoto Yabuuchi

Makoto Yabuuchi 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: 20180350438
    Abstract: An object of the present disclosure is to provide a content addressable memory realizing higher speed of a search access. A content addressable memory includes: a plurality of memory cells; a match line coupled to the plurality of memory cells; a search line coupled to each of the plurality of memory cells; a match line output circuit coupled to the match line; and a potential changing circuit coupled to the match line and changing the potential of the match line.
    Type: Application
    Filed: March 20, 2018
    Publication date: December 6, 2018
    Inventor: Makoto Yabuuchi
  • Publication number: 20180350437
    Abstract: A content addressable memory includes a plurality of TCAM cells which configure one entry, a first word line coupled to the TCAM cells, a second word line coupled to the TCAM cells and a match line coupled to the TCAM cells and further includes a valid cell which stores a valid bit which indicates validity or invalidity of the entry, a bit line coupled to the valid line and a selection circuit which is coupled to the first word line and the second word line and sets the valid cell to a selected state in accordance with a situation where the first word line or the second word line is set to the selected state.
    Type: Application
    Filed: March 20, 2018
    Publication date: December 6, 2018
    Inventors: Yohei Sawada, Makoto Yabuuchi, Masao Morimoto
  • Publication number: 20180350792
    Abstract: An area of a semiconductor device having a FINFET can be reduced. The drain regions of an n-channel FINFET and a p-channel FINFET are extracted by two second local interconnects from a second Y gird between a gate electrode and a dummy gate adjacent thereto, to a third Y grid adjacent to the second Y gird. These second local interconnects are connected by a first local interconnect extending in the X direction in the third Y grid. According to such a cell layout, although the number of grids is increased by one because of the arrangement of the first local interconnect, the length in the X direction can be reduced. As a result, the cell area of the unit cell can be reduced while a space between the first and second local interconnects is secured.
    Type: Application
    Filed: August 6, 2018
    Publication date: December 6, 2018
    Applicant: Renesas Electronics Corporation
    Inventors: Takeshi OKAGAKI, Koji SHIBUTANI, Makoto YABUUCHI, Nobuhiro TSUDA
  • Publication number: 20180342522
    Abstract: In a region just below an access gate electrode in an SRAM memory cell, a second halo region is formed adjacent to a source-drain region and a first halo region is formed adjacent to a first source-drain region. In a region just below a drive gate electrode, a third halo region is formed adjacent to the third source-drain region and a fourth halo region is formed adjacent to a fourth source-drain region. The second halo region is set to have an impurity concentration higher than the impurity concentration of the first halo region. The third halo region is set to have an impurity concentration higher than the impurity concentration of the fourth halo region. The impurity concentration of the first halo region and the impurity concentration of the fourth halo region are different from each other.
    Type: Application
    Filed: June 21, 2018
    Publication date: November 29, 2018
    Inventors: Koji NII, Makoto YABUUCHI, Yasumasa TSUKAMOTO, Kengo MASUDA
  • Publication number: 20180340978
    Abstract: An object of the present invention is to provide a highly-reliable content addressable memory. Provided is a content addressable memory including: a plurality of CAM cells; a word line joined to the CAM cells; a plurality of bit lines joined to the CAM cells; a plurality of search lines joined to the CAM cells; a match line joined to the CAM cells; a match amplifier joined to the match line; and a selection circuit that can select the output of the match amplifier in accordance with the value of the word line.
    Type: Application
    Filed: March 8, 2018
    Publication date: November 29, 2018
    Inventors: Makoto YABUUCHI, Shinji TANAKA
  • Publication number: 20180315471
    Abstract: A semiconductor storage device having a plurality of low power consumption modes is provided. The semiconductor storage device includes a plurality of memory modules where a plurality of low power consumption modes can be set and cancelled based on a first and a second control signals. At least a part of memory modules of the plurality of memory modules have a propagation path that propagates an inputted first control signal to a post stage memory module. The second control signal is inputted into each of the plurality of memory modules in parallel. Setting and cancelling of the first low power consumption mode of each memory module are performed based on a combination of the first control signal that is propagated through the propagation path and the second control signal.
    Type: Application
    Filed: July 10, 2018
    Publication date: November 1, 2018
    Inventors: Makoto YABUUCHI, Shinji TANAKA
  • Patent number: 10102899
    Abstract: A semiconductor device includes a SRAM circuit. The SRAM circuit includes: a memory array having a plurality of memory cells arranged in a matrix; a ground interconnection commonly connected to each of the memory cells; and a first potential control circuit for controlling a potential of the ground interconnection depending on an operation mode. The first potential control circuit includes a first NMOS transistor and a first PMOS transistor connected in parallel to each other between a ground node providing a ground potential and the ground interconnection.
    Type: Grant
    Filed: March 31, 2015
    Date of Patent: October 16, 2018
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Yohei Sawada, Makoto Yabuuchi, Yuichiro Ishii
  • Publication number: 20180261280
    Abstract: A semiconductor device with a memory unit of which the variations in the operation timing are reduced is provided. For example, the semiconductor device is provided with dummy bit lines which are arranged collaterally with a proper bit line, and column direction load circuits which are sequentially coupled to the dummy bit lines. Each column direction load circuit is provided with plural NMOS transistors fixed to an off state, predetermined ones of which have the source and the drain suitably coupled to any of the dummy bit lines. Load capacitance accompanying diffusion layer capacitance of the predetermined NMOS transistors is added to the dummy bit lines, and corresponding to the load capacitance, the delay time from a decode activation signal to a dummy bit line signal is set up. The dummy bit line signal is employed when setting the start-up timing of a sense amplifier.
    Type: Application
    Filed: May 16, 2018
    Publication date: September 13, 2018
    Applicant: Renesas Electronics Corporation
    Inventors: Shinji TANAKA, Makoto YABUUCHI, Yuta YOSHIDA
  • Patent number: 10068891
    Abstract: An area of a semiconductor device having a FINFET can be reduced. The drain regions of an n-channel FINFET and a p-channel FINFET are extracted by two second local interconnects from a second Y gird between a gate electrode and a dummy gate adjacent thereto, to a third Y grid adjacent to the second Y gird. These second local interconnects are connected by a first local interconnect extending in the X direction in the third Y grid. According to such a cell layout, although the number of grids is increased by one because of the arrangement of the first local interconnect, the length in the X direction can be reduced. As a result, the cell area of the unit cell can be reduced while a space between the first and second local interconnects is secured.
    Type: Grant
    Filed: September 29, 2017
    Date of Patent: September 4, 2018
    Assignee: Renesas Electronics Corporation
    Inventors: Takeshi Okagaki, Koji Shibutani, Makoto Yabuuchi, Nobuhiro Tsuda
  • Publication number: 20180240514
    Abstract: There is provided, for example, a write assist circuit for controlling the voltage level of a memory cell power supply line coupled to an SRAM memory cell to be written in the write operation. The write assist circuit reduces the voltage level of the memory cell power supply line to a predetermined voltage level, in response to a write assist enable signal that is enabled in the write operation. At the same time, the write assist circuit controls the reduction speed of the voltage level of the memory cell power supply line, according to the pulse width of a write assist pulse signal. The pulse width of the write assist pulse signal is defined in such a way that the greater the number of rows (or the longer the length of the memory cell power supply line), the greater the pulse width.
    Type: Application
    Filed: April 19, 2018
    Publication date: August 23, 2018
    Inventor: Makoto Yabuuchi
  • Publication number: 20180240513
    Abstract: A semiconductor storage device provided can increase a write margin and suppress increase of a chip area. The semiconductor storage device includes plural memory cells arranged in a matrix; plural bit-line pairs arranged corresponding to each column of the memory cells; a write driver circuit which transmits data to a bit-line pair of a selected column according to write data; and a write assist circuit which drives a bit line on a low potential side of the bit-line pair of a selected column to a negative voltage level. The write assist circuit includes first signal wiring; a first driver circuit which drives the first signal wiring according to a control signal; and second signal wiring which is coupled to the bit line on the low-potential side and generates a negative voltage by the driving of the first driver circuit, based on inter-wire coupling capacitance with the first signal wiring.
    Type: Application
    Filed: April 19, 2018
    Publication date: August 23, 2018
    Inventors: Toshiaki SANO, Ken SHIBATA, Shinji TANAKA, Makoto YABUUCHI, Noriaki MAEDA
  • Patent number: 10049723
    Abstract: A semiconductor storage device having a plurality of low power consumption modes is provided. The semiconductor storage device includes a plurality of memory modules where a plurality of low power consumption modes can be set and cancelled based on a first and a second control signals. At least a part of memory modules of the plurality of memory modules have a propagation path that propagates an inputted first control signal to a post stage memory module. The second control signal is inputted into each of the plurality of memory modules in parallel. Setting and cancelling of the first low power consumption mode of each memory module are performed based on a combination of the first control signal that is propagated through the propagation path and the second control signal.
    Type: Grant
    Filed: May 26, 2017
    Date of Patent: August 14, 2018
    Assignee: Renesas Electronics Corporation
    Inventors: Makoto Yabuuchi, Shinji Tanaka
  • Publication number: 20180211956
    Abstract: Data hold time is controlled without excessively increasing a circuit area. A semiconductor device includes a data buffer and a flip-flop formed of fin. As a delay line, gate wirings being in the same layer as gate electrodes of the fin are provided in a data signal path from a data output node of the data buffer to a data input node of the flip-flop.
    Type: Application
    Filed: March 19, 2018
    Publication date: July 26, 2018
    Inventor: Makoto YABUUCHI
  • Patent number: 10032781
    Abstract: In a region just below an access gate electrode in an SRAM memory cell, a second halo region is formed adjacent to a source-drain region and a first halo region is formed adjacent to a first source-drain region. In a region just below a drive gate electrode, a third halo region is formed adjacent to the third source-drain region and a fourth halo region is formed adjacent to a fourth source-drain region. The second halo region is set to have an impurity concentration higher than the impurity concentration of the first halo region. The third halo region is set to have an impurity concentration higher than the impurity concentration of the fourth halo region. The impurity concentration of the first halo region and the impurity concentration of the fourth halo region are different from each other.
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: July 24, 2018
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Koji Nii, Makoto Yabuuchi, Yasumasa Tsukamoto, Kengo Masuda
  • Publication number: 20180204613
    Abstract: There is provided a semiconductor integrated circuit device that can generate a unique ID with the suppression of overhead. When a unique ID is generated, the potential of a word line of a memory cell in an SRAM is raised above the power supply voltage of the SRAM, and then lowered below the power supply voltage of the SRAM. When the potential of the word line is above the power supply voltage of the SRAM, the same data is supplied to both the bit lines of the memory cell. Thereby, the memory cell in the SRAM is put into an undefined state and then changed so as to hold data according to characteristics of elements or the like configuring the memory cell. In the manufacture of the SRAM, there occur variations in characteristics of elements or the like configuring the memory cell. Accordingly, the memory cell in the SRAM holds data according to variations occurring in the manufacture.
    Type: Application
    Filed: March 13, 2018
    Publication date: July 19, 2018
    Applicant: Renesas Electronics Corporation
    Inventors: Makoto YABUUCHI, Hidehiro FUJIWARA
  • Patent number: 10002662
    Abstract: A semiconductor device with a memory unit of which the variations in the operation timing are reduced is provided. For example, the semiconductor device is provided with dummy bit lines which are arranged collaterally with a proper bit line, and column direction load circuits which are sequentially coupled to the dummy bit lines. Each column direction load circuit is provided with plural NMOS transistors fixed to an off state, predetermined ones of which have the source and the drain suitably coupled to any of the dummy bit lines. Load capacitance accompanying diffusion layer capacitance of the predetermined NMOS transistors is added to the dummy bit lines, and corresponding to the load capacitance, the delay time from a decode activation signal to a dummy bit line signal is set up. The dummy bit line signal is employed when setting the start-up timing of a sense amplifier.
    Type: Grant
    Filed: September 27, 2017
    Date of Patent: June 19, 2018
    Assignee: Renesas Electronics Corporation
    Inventors: Shinji Tanaka, Makoto Yabuuchi, Yuta Yoshida
  • Publication number: 20180158522
    Abstract: A circuit includes a memory cell array which includes: a plurality of memory cells; a plurality of word lines coupled to the memory cells, respectively, and a plurality of bit lines coupled to the memory cells, an address control circuit which includes: a first latch circuit into which a first address signal is input and from which a first output signal is output; a selection circuit into which a second address signal and the first output signal are input and which selects the first output signal or the second address signal for outputting the first output signal or the second address signal as a second output signal; a second latch circuit into which the second output signal is input and from which a third output signal is output; a decode circuit which decodes the third output signal and outputs a fourth output signal; and a word line drive circuit.
    Type: Application
    Filed: January 31, 2018
    Publication date: June 7, 2018
    Inventors: Yuichiro ISHII, Makoto YABUUCHI, Masao MORIMOTO
  • Publication number: 20180158513
    Abstract: The semiconductor device includes a supply circuit for supplying a boosted voltage to a distal end of a wiring driven by a drive signal. The supply circuit includes an inverter circuit having an input coupled to the wiring, and a switch element controlled by an output signal of the inverter circuit. The switch element couples the boosted voltage to the distal end of the wiring.
    Type: Application
    Filed: November 14, 2017
    Publication date: June 7, 2018
    Applicant: Renesas Electronics Corporation
    Inventors: Shinji TANAKA, Makoto YABUUCHI
  • Patent number: 9984743
    Abstract: There is provided, for example, a write assist circuit for controlling the voltage level of a memory cell power supply line coupled to an SRAM memory cell to be written in the write operation. The write assist circuit reduces the voltage level of the memory cell power supply line to a predetermined voltage level, in response to a write assist enable signal that is enabled in the write operation. At the same time, the write assist circuit controls the reduction speed of the voltage level of the memory cell power supply line, according to the pulse width of a write assist pulse signal. The pulse width of the write assist pulse signal is defined in such a way that the greater the number of rows (or the longer the length of the memory cell power supply line), the greater the pulse width.
    Type: Grant
    Filed: June 21, 2017
    Date of Patent: May 29, 2018
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventor: Makoto Yabuuchi
  • Patent number: 9984767
    Abstract: A semiconductor device having a capability of generating chip identification information includes: an SRAM macro having a plurality of memory cells arranged in rows and columns; a test address storage unit configured to store a test address; a self-diagnostic circuit configured to output the test address based on a result of confirmation of operation of the memory cell selected by the test address; and an identification information generation circuit configured to generate chip identification information based on the test address which is output by the self-diagnostic circuit.
    Type: Grant
    Filed: August 18, 2016
    Date of Patent: May 29, 2018
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Hidehiro Fujiwara, Makoto Yabuuchi, Koji Nii, Yoshikazu Saito