Patents by Inventor Futoshi Igaue

Futoshi Igaue 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).

  • Patent number: 10910055
    Abstract: The present invention provides a semiconductor device that can reduce the power consumption, including: a plurality of search memory cells arranged in a matrix; a plurality of match lines provided corresponding to each memory cell row to determine match/mismatch between data stored in the search memory cell and search data; a plurality of match line retention circuits provided corresponding to each of the match lines; a storage unit for storing information relating to the state of each of the match lines; and a selection circuit for selectively activating the match line retention circuits based on the information stored in the storage unit.
    Type: Grant
    Filed: September 20, 2018
    Date of Patent: February 2, 2021
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventor: Futoshi Igaue
  • Patent number: 10366755
    Abstract: The consumption current of a TCAM device is reduced. A semiconductor device includes multiple sub-arrays each including a TCAM cell array. Each sub-array searches the corresponding part of the input search data. Each sub-array outputs the search result indicative of a match for every entry without searching, when the corresponding first control signal is activated.
    Type: Grant
    Filed: August 6, 2018
    Date of Patent: July 30, 2019
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Naoya Watanabe, Futoshi Igaue
  • Publication number: 20190164608
    Abstract: The present invention provides a semiconductor device that can reduce the power consumption, including: a plurality of search memory cells arranged in a matrix; a plurality of match lines provided corresponding to each memory cell row to determine match/mismatch between data stored in the search memory cell and search data; a plurality of match line retention circuits provided corresponding to each of the match lines; a storage unit for storing information relating to the state of each of the match lines; and a selection circuit for selectively activating the match line retention circuits based on the information stored in the storage unit.
    Type: Application
    Filed: September 20, 2018
    Publication date: May 30, 2019
    Inventor: Futoshi IGAUE
  • Publication number: 20180350439
    Abstract: The consumption current of a TCAM device is reduced. A semiconductor device includes multiple sub-arrays each including a TCAM cell array. Each sub-array searches the corresponding part of the input search data. Each sub-array outputs the search result indicative of a match for every entry without searching, when the corresponding first control signal is activated.
    Type: Application
    Filed: August 6, 2018
    Publication date: December 6, 2018
    Inventors: Naoya WATANABE, Futoshi IGAUE
  • Patent number: 10121541
    Abstract: The present invention makes it possible to form a circuit configuration that is capable of executing a keyword search at an increased speed while suppressing an increase in the memory capacity of a content-addressable memory. A semiconductor device according to an aspect of the present invention searches an input data string for a predesignated keyword, and includes a first content-addressable memory that stores a partial keyword corresponding to a predetermined number of data beginning with the first data of the keyword, a second content-addressable memory that stores the entirety of the keyword, and a control circuit that is coupled to the first content-addressable memory and to the second content-addressable memory. When a portion matching the partial keyword is detected in the input data string by a search in the first content-addressable memory, the second content-addressable memory executes a search on search data extracted from the input data string.
    Type: Grant
    Filed: August 4, 2016
    Date of Patent: November 6, 2018
    Assignee: Renesas Electronics Corporation
    Inventors: Futoshi Igaue, Kenji Yoshinaga, Naoya Watanabe, Mihoko Akiyama
  • Patent number: 10068646
    Abstract: The consumption current of a TCAM device is reduced. A semiconductor device includes multiple sub-arrays each including a TCAM cell array. Each sub-array searches the corresponding part of the input search data. Each sub-array outputs the search result indicative of a match for every entry without searching, when the corresponding first control signal is activated.
    Type: Grant
    Filed: October 18, 2017
    Date of Patent: September 4, 2018
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Naoya Watanabe, Futoshi Igaue
  • Publication number: 20180040373
    Abstract: The consumption current of a TCAM device is reduced. A semiconductor device includes multiple sub-arrays each including a TCAM cell array. Each sub-array searches the corresponding part of the input search data. Each sub-array outputs the search result indicative of a match for every entry without searching, when the corresponding first control signal is activated.
    Type: Application
    Filed: October 18, 2017
    Publication date: February 8, 2018
    Inventors: Naoya WATANABE, Futoshi IGAUE
  • Patent number: 9824757
    Abstract: The consumption current of a TCAM device is reduced. A semiconductor device includes multiple sub-arrays each including a TCAM cell array. Each sub-array searches the corresponding part of the input search data. Each sub-array outputs the search result indicative of a match for every entry without searching, when the corresponding first control signal is activated.
    Type: Grant
    Filed: August 3, 2016
    Date of Patent: November 21, 2017
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Naoya Watanabe, Futoshi Igaue
  • Publication number: 20170060438
    Abstract: The present invention makes it possible to form a circuit configuration that is capable of executing a keyword search at an increased speed while suppressing an increase in the memory capacity of a content-addressable memory. A semiconductor device according to an aspect of the present invention searches an input data string for a predesignated keyword, and includes a first content-addressable memory that stores a partial keyword corresponding to a predetermined number of data beginning with the first data of the keyword, a second content-addressable memory that stores the entirety of the keyword, and a control circuit that is coupled to the first content-addressable memory and to the second content-addressable memory. When a portion matching the partial keyword is detected in the input data string by a search in the first content-addressable memory, the second content-addressable memory executes a search on search data extracted from the input data string.
    Type: Application
    Filed: August 4, 2016
    Publication date: March 2, 2017
    Inventors: Futoshi IGAUE, Kenji YOSHINAGA, Naoya WATANABE, Mihoko AKIYAMA
  • Publication number: 20170062051
    Abstract: The consumption current of a TCAM device is reduced. A semiconductor device includes multiple sub-arrays each including a TCAM cell array. Each sub-array searches the corresponding part of the input search data. Each sub-array outputs the search result indicative of a match for every entry without searching, when the corresponding first control signal is activated.
    Type: Application
    Filed: August 3, 2016
    Publication date: March 2, 2017
    Inventors: Naoya WATANABE, Futoshi IGAUE
  • Patent number: 8599639
    Abstract: A semiconductor integrated circuit device has a negative voltage generation circuit provided at each power supply circuit unit for six memory macros. Therefore, the response with respect to variation in a negative voltage is increased. In a standby mode, a negative voltage supply line for the six memory macros is connected by a switch circuit, and only a negative voltage generation circuit of one power supply circuit unit among six negative voltage generation circuits of the six power supply circuit units is rendered active. Thus, increase in standby current can be prevented.
    Type: Grant
    Filed: May 22, 2013
    Date of Patent: December 3, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Mihoko Akiyama, Futoshi Igaue, Kenji Yoshinaga, Masashi Matsumura, Fukashi Morishita
  • Publication number: 20130249624
    Abstract: A semiconductor integrated circuit device has a negative voltage generation circuit provided at each power supply circuit unit for six memory macros. Therefore, the response with respect to variation in a negative voltage is increased. In a standby mode, a negative voltage supply line for the six memory macros is connected by a switch circuit, and only a negative voltage generation circuit of one power supply circuit unit among six negative voltage generation circuits of the six power supply circuit units is rendered active. Thus, increase in standby current can be prevented.
    Type: Application
    Filed: May 22, 2013
    Publication date: September 26, 2013
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventors: Mihoko AKIYAMA, Futoshi IGAUE, Kenji YOSHINAGA, Masashi MATSUMURA, Fukashi MORISHITA
  • Patent number: 8451678
    Abstract: A semiconductor integrated circuit device has a negative voltage generation circuit provided at each power supply circuit unit for six memory macros. Therefore, the response with respect to variation in a negative voltage is increased. In a standby mode, a negative voltage supply line for the six memory macros is connected by a switch circuit, and only a negative voltage generation circuit of one power supply circuit unit among six negative voltage generation circuits of the six power supply circuit units is rendered active. Thus, increase in standby current can be prevented.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: May 28, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Mihoko Akiyama, Futoshi Igaue, Kenji Yoshinaga, Masashi Matsumura, Fukashi Morishita
  • Patent number: 8004923
    Abstract: A semiconductor integrated circuit device has a negative voltage generation circuit provided at each power supply circuit unit for six memory macros. Therefore, the response with respect to variation in a negative voltage is increased. In a standby mode, a negative voltage supply line for the six memory macros is connected by a switch circuit, and only a negative voltage generation circuit of one power supply circuit unit among six negative voltage generation circuits of the six power supply circuit units is rendered active. Thus, increase in standby current can be prevented.
    Type: Grant
    Filed: January 7, 2010
    Date of Patent: August 23, 2011
    Assignee: Renesas Electronics Corporation
    Inventors: Mihoko Akiyama, Futoshi Igaue, Kenji Yoshinaga, Masashi Matsumura, Fukashi Morishita
  • Publication number: 20110182131
    Abstract: A semiconductor integrated circuit device has a negative voltage generation circuit provided at each power supply circuit unit for six memory macros. Therefore, the response with respect to variation in a negative voltage is increased. In a standby mode, a negative voltage supply line for the six memory macros is connected by a switch circuit, and only a negative voltage generation circuit of one power supply circuit unit among six negative voltage generation circuits of the six power supply circuit units is rendered active. Thus, increase in standby current can be prevented.
    Type: Application
    Filed: April 5, 2011
    Publication date: July 28, 2011
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventors: Mihoko Akiyama, Futoshi Igaue, Kenji Yoshinaga, Masashi Matsumura, Fukashi Morishita
  • Publication number: 20100109761
    Abstract: A semiconductor integrated circuit device has a negative voltage generation circuit provided at each power supply circuit unit for six memory macros. Therefore, the response with respect to variation in a negative voltage is increased. In a standby mode, a negative voltage supply line for the six memory macros is connected by a switch circuit, and only a negative voltage generation circuit of one power supply circuit unit among six negative voltage generation circuits of the six power supply circuit units is rendered active. Thus, increase in standby current can be prevented.
    Type: Application
    Filed: January 7, 2010
    Publication date: May 6, 2010
    Applicant: Renesas Technology Corp.
    Inventors: Mihoko Akiyama, Futoshi Igaue, Kenji Yoshinaga, Masashi Matsumura, Fukashi Morishita
  • Patent number: 7656736
    Abstract: A semiconductor integrated circuit device has a negative voltage generation circuit provided at each power supply circuit unit for six memory macros. Therefore, the response with respect to variation in a negative voltage is increased. In a standby mode, a negative voltage supply line for the six memory macros is connected by a switch circuit, and only a negative voltage generation circuit of one power supply circuit unit among six negative voltage generation circuits of the six power supply circuit units is rendered active. Thus, increase in standby current can be prevented.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: February 2, 2010
    Assignee: Renesas Technology Corp.
    Inventors: Mihoko Akiyama, Futoshi Igaue, Kenji Yoshinaga, Masashi Matsumura, Fukashi Morishita
  • Publication number: 20080298156
    Abstract: A semiconductor device has a first operation mode and a second operation mode in which power supply with a higher voltage value than that in the first operation mode is provided. The semiconductor device includes a memory portion having memory cells for storing data and a power supply circuit portion supplying a first voltage and a second voltage to the memory portion. The memory portion writes or reads data to or from the memory cells based on the first voltage and the second voltage, and the power supply circuit portion provides a smaller voltage difference between the first voltage and the second voltage in the second operation mode as compared with the voltage difference in the first operation mode.
    Type: Application
    Filed: July 9, 2008
    Publication date: December 4, 2008
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Kenji YOSHINAGA, Masashi Matsumura, Futoshi Igaue, Mihoko Akiyama, Fukashi Morishita
  • Patent number: 7408818
    Abstract: A semiconductor device has a first operation mode and a second operation mode in which power supply with a higher voltage value than that in the first operation mode is provided. The semiconductor device includes a memory portion having memory cells for storing data and a power supply circuit portion supplying a first voltage and a second voltage to the memory portion. The memory portion writes or reads data to or from the memory cells based on the first voltage and the second voltage, and the power supply circuit portion provides a smaller voltage difference between the first voltage and the second voltage in the second operation mode as compared with the voltage difference in the first operation mode.
    Type: Grant
    Filed: February 8, 2007
    Date of Patent: August 5, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Kenji Yoshinaga, Masashi Matsumura, Futoshi Igaue, Mihoko Akiyama, Fukashi Morishita
  • Publication number: 20070216467
    Abstract: A semiconductor integrated circuit device has a negative voltage generation circuit provided at each power supply circuit unit for six memory macros. Therefore, the response with respect to variation in a negative voltage is increased. In a standby mode, a negative voltage supply line for the six memory macros is connected by a switch circuit, and only a negative voltage generation circuit of one power supply circuit unit among six negative voltage generation circuits of the six power supply circuit units is rendered active. Thus, increase in standby current can be prevented.
    Type: Application
    Filed: March 14, 2007
    Publication date: September 20, 2007
    Inventors: Mihoko Akiyama, Futoshi Igaue, Kenji Yoshinaga, Masashi Matsumura, Fukashi Morishita