Patents by Inventor Takashi Hirao

Takashi Hirao 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: 11127695
    Abstract: A power conversion device includes first and second power semiconductor elements, and a circuit for transferring a drive signal of the first and second power semiconductor elements. The circuit board includes a first emitter wire which is formed along an arranging direction of the first power semiconductor element and the second power semiconductor element, a first gate wire which is disposed between the first power semiconductor element and the first emitter wire, a second gate wire which is disposed between the second power semiconductor element and the emitter wire, a third gate wire which is disposed to face the first gate wire and the second gate wire with the emitter wire interposed between the third gate wire and the first gate wire and the second gate wire, and a first gate resistor which connects the first gate wire and the third gate wire over the first emitter wire.
    Type: Grant
    Filed: July 27, 2018
    Date of Patent: September 21, 2021
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Akihiro Namba, Takashi Hirao, Masami Oonishi
  • Publication number: 20210280483
    Abstract: A power semiconductor apparatus includes a power semiconductor element having low and high potential side electrodes and a sense electrode, high and low potential side conductors electrically connected with the high potential side electrodes, respectively, a sense wiring electrically connected with the sense electrode, and a first metal portion facing the low potential side conductor or the low potential side conductor across the sense wiring. When viewed from an array direction of the sense wiring and the first metal portion, the sense wiring has a facing portion facing the high or low potential side conductor, the first metal portion forms a recess in a part overlapping the facing portion, and a depth of the recess is formed such that a distance between a bottom of the recess and the sense wiring is larger than a distance between the sense wiring and the high or low potential side conductor.
    Type: Application
    Filed: July 11, 2019
    Publication date: September 9, 2021
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Hironori NAGASAKI, Shintaro TANAKA, Takashi HIRAO
  • Publication number: 20210272882
    Abstract: Detection accuracy of a collector sense in detecting a voltage is improved. A power module 300 has a first conductor 410 and a second conductor 411 to which a plurality of active elements 317 and 315 configuring upper and lower arm circuits are connected. In addition, the power module 300 has an AC side terminal 320B protruding from one side 301a, a positive electrode side terminal 315B and a negative electrode side terminal 319B which protrude from the other side 301b, an intermediate electrode portion 414 that connects the first conductor 410 and the second conductor 411 to each other, and a collector sense wiring 452a in which a collector electrode of an active element 157 and the first conductor 410 are connected to each other via a sense connection portion 415.
    Type: Application
    Filed: June 19, 2019
    Publication date: September 2, 2021
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Nobutake TSUYUNO, Takashi HIRAO, Akira MATSUSHITA
  • Patent number: 11056415
    Abstract: To improve yield and reliability at the time when a plurality of semiconductor elements used for a semiconductor device is arranged in parallel.
    Type: Grant
    Filed: July 19, 2017
    Date of Patent: July 6, 2021
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Masami Oonishi, Takashi Hirao
  • Publication number: 20210074647
    Abstract: An object of the present invention is to improve assemblability of a power semiconductor device. A power semiconductor device includes a plurality of submodules that includes a semiconductor element interposed between a source conductor and a drain conductor, a sense wiring that transmits a sense signal of the semiconductor element, and an insulating portion at which the sense wiring and the sense conductor are arranged, and a source outer conductor that is formed to surround the source conductor and is joined to the source conductor in each of the plurality of submodules. Each source conductor included in the plurality of submodules includes protrusion portions that are formed toward the sensor wiring from the source conductor, are connected to the sense wiring, and define a distance between the sense wiring and the source outer conductor.
    Type: Application
    Filed: February 7, 2019
    Publication date: March 11, 2021
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Takashi HIRAO, Haruka SHIMIZU
  • Patent number: 10928428
    Abstract: The present invention aims to reduce the leakage current that flows when measuring a high voltage and includes: a voltage detector that detects a voltage and outputs a detection voltage; a current supplier that supplies a measurement current across a pair of input terminals via a protective resistor; and a processor that executes a voltage measurement process, which measures the voltage based on data indicating the detection voltage, and a resistance measurement process, which measures a resistance connected between the input terminals based on the voltage and the current. A first switch is connected in parallel to the protective resistor and the processor executes the voltage measurement process in a state where the first switch has been set open to measure the terminal voltage, and executes the resistance measurement process by setting the first switch shorted when the voltage is equal to or below the reference voltage value.
    Type: Grant
    Filed: January 11, 2019
    Date of Patent: February 23, 2021
    Assignee: HIOKI DENKI KABUSHIKI KAISHA
    Inventors: Tetsuya Nakamura, Takashi Hirao, Yuta Akamatsu, Yuta Suzuki
  • Patent number: 10884030
    Abstract: In an object of the present invention, an object is to provide a technique for achieving higher accuracy in current detection of a radio frequency current, in a current detection device. The current detection device of the present invention includes two or more conductors through which a current shunted from a same conductor flows; conductors through which the shunted current flows have portions opposed to each other; currents flow in opposite directions in opposing portions of the conductors; and a magnetic field detecting element is provided between the opposing portions of the conductors.
    Type: Grant
    Filed: December 4, 2017
    Date of Patent: January 5, 2021
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Takashi Hirao, Akihiro Namba
  • Publication number: 20200258853
    Abstract: A power conversion device includes first and second power semiconductor elements, and a circuit for transferring a drive signal of the first and second power semiconductor elements. The circuit board includes a first emitter wire which is formed along an arranging direction of the first power semiconductor element and the second power semiconductor element, a first gate wire which is disposed between the first power semiconductor element and the first emitter wire, a second gate wire which is disposed between the second power semiconductor element and the emitter wire, a third gate wire which is disposed to face the first gate wire and the second gate wire with the emitter wire interposed between the third gate wire and the first gate wire and the second gate wire, and a first gate resistor which connects the first gate wire and the third gate wire over the first emitter wire.
    Type: Application
    Filed: July 27, 2018
    Publication date: August 13, 2020
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Akihiro NAMBA, Takashi HIRAO, Masami OONISHI
  • Publication number: 20200227333
    Abstract: An object of the present invention is to provide a power semiconductor device enabling maintenance in reliability and improvement in productivity. According to the present invention, provided are: a circuit body including a semiconductor element and a conductive portion; a first insulation and a second insulation opposed to each other, the circuit body being interposed between the first insulation and the second insulation; a first base and a second base opposed to each other, the circuit body, the first insulation, and the second insulation being interposed between the first base and the second base; a case having a first opening portion covered with the first base and a second opening portion covered with the second base; and a distance regulation portion provided in space between the first base and the second base, the distance regulation portion regulating a distance between the first base and the second base in contact with the first base and the second base.
    Type: Application
    Filed: May 22, 2018
    Publication date: July 16, 2020
    Inventors: Nobutake TSUYUNO, Hiromi SHIMAZU, Akihiro NAMBA, Akira MATSUSHITA, Hiroshi HOUZOUJI, Atsuo NISHIHARA, Toshiaki ISHII, Takashi HIRAO
  • Publication number: 20190271724
    Abstract: In an object of the present invention, an object is to provide a technique for achieving higher accuracy in current detection of a radio frequency current, in a current detection device. The current detection device of the present invention includes two or more conductors through which a current shunted from a same conductor flows; conductors through which the shunted current flows have portions opposed to each other; currents flow in opposite directions in opposing portions of the conductors; and a magnetic field detecting element is provided between the opposing portions of the conductors.
    Type: Application
    Filed: December 4, 2017
    Publication date: September 5, 2019
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Takashi HIRAO, Akihiro NAMBA
  • Publication number: 20190229032
    Abstract: To improve yield and reliability at the time when a plurality of semiconductor elements used for a semiconductor device is arranged in parallel.
    Type: Application
    Filed: July 19, 2017
    Publication date: July 25, 2019
    Inventors: Masami OONISHI, Takashi HIRAO
  • Publication number: 20190146018
    Abstract: The present invention aims to reduce the leakage current that flows when measuring a high voltage and includes: a voltage detector that detects a voltage and outputs a detection voltage; a current supplier that supplies a measurement current across a pair of input terminals via a protective resistor; and a processor that executes a voltage measurement process, which measures the voltage based on data indicating the detection voltage, and a resistance measurement process, which measures a resistance connected between the input terminals based on the voltage and the current. A first switch is connected in parallel to the protective resistor and the processor executes the voltage measurement process in a state where the first switch has been set open to measure the terminal voltage, and executes the resistance measurement process by setting the first switch shorted when the voltage is equal to or below the reference voltage value.
    Type: Application
    Filed: January 11, 2019
    Publication date: May 16, 2019
    Applicant: HIOKI DENKI KABUSHIKI KAISHA
    Inventors: Tetsuya NAKAMURA, Takashi HIRAO, Yuta AKAMATSU, Yuta SUZUKI
  • Patent number: 10109549
    Abstract: In order to improve productivity of a semiconductor device, while improving stability of the blocking voltage of the semiconductor device, this semiconductor device is characterized by having a semiconductor element, and a laminated structure having three resin layers, said laminated structure being in a peripheral section surrounding a main electrode on one surface of the semiconductor element. The semiconductor device is also characterized in that the laminated structure has, on the center section side of the semiconductor element, a region where a lower resin layer is in contact with an intermediate resin layer, and a region where the lower resin layer is in contact with an upper resin layer.
    Type: Grant
    Filed: December 24, 2014
    Date of Patent: October 23, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Hirao, Kan Yasui, Kazuhiro Suzuki
  • Publication number: 20180267715
    Abstract: According to one embodiment, the memory system includes a nonvolatile memory including a plurality of blocks, and a controller circuit that controls execution of a data writing process and a garbage collection process. Each of the blocks is an unit of erasure. The data writing process includes a process of writing user data into the nonvolatile memory in accordance with a request from an external member. The garbage collection process includes a process of moving valid data in at least a first block into a second block among the blocks and invalidating the valid data in the first block to be erasable. Upon receiving a data write request from the external member, the controller circuit controls a length of a waiting time to be provided before or after the data writing process within a period from receiving the write request to returning a response to the external member.
    Type: Application
    Filed: March 8, 2018
    Publication date: September 20, 2018
    Applicant: Toshiba Memory Corporation
    Inventors: Hiroki Matsudaira, Norio Aoyama, Ryoichi Kato, Taku Ooneda, Takashi Hirao, Aurelien Nam Phong Tran, Hiroyuki Yamaguchi, Takuya Suzuki, Hajime Yamazaki
  • Publication number: 20170352604
    Abstract: In order to improve productivity of a semiconductor device, while improving stability of the blocking voltage of the semiconductor device, this semiconductor device is characterized by having a semiconductor element, and a laminated structure having three resin layers, said laminated structure being in a peripheral section surrounding a main electrode on one surface of the semiconductor element. The semiconductor device is also characterized in that the laminated structure has, on the center section side of the semiconductor element, a region where a lower resin layer is in contact with an intermediate resin layer, and a region where the lower resin layer is in contact with an upper resin layer.
    Type: Application
    Filed: December 24, 2014
    Publication date: December 7, 2017
    Applicant: Hitachi, Ltd.
    Inventors: Takashi HIRAO, Kan YASUI, Kazuhiro SUZUKI
  • Patent number: 9711590
    Abstract: There is provided a semiconductor device including corundum crystal films of good quality. There is provided a semiconductor device including a base substrate, a semiconductor layer, and an insulating film each having a corundum crystal structure. Materials having a corundum crystal structure include many types of oxide films capable of functioning as an insulating film. Since all the base substrate, the semiconductor layer, and the insulating film have a corundum crystal structure, it is possible to achieve a semiconductor layer and an insulating film of good quality on the base substrate.
    Type: Grant
    Filed: September 24, 2013
    Date of Patent: July 18, 2017
    Assignee: FLOSFIA, INC.
    Inventors: Kentaro Kaneko, Toshimi Hitora, Takashi Hirao
  • Patent number: 9654027
    Abstract: A semiconductor device is provided that can prevent a current from being concentrated into a specific chip, and can reduce loss as well as noise. The semiconductor device according to the present invention includes: a switching element; a main diode that is connected in parallel to the switching element; and an auxiliary diode that is connected in parallel to the switching element and has a different structure from that of the main diode, wherein in a conductive state a current flowing through the auxiliary diode is smaller than that through the main diode, and in a transition period from the conductive state to a non-conductive state a current flowing through the auxiliary diode is larger than that through the main diode.
    Type: Grant
    Filed: May 22, 2015
    Date of Patent: May 16, 2017
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Hirao, Mutsuhiro Mori
  • Patent number: 9304906
    Abstract: According to one embodiment, a memory system includes non-volatile memory, a block management table that stores whether data in the non-volatile memory is valid or invalid in a unit of cluster, and a controller configured to execute compaction. In the block management table, first information related to likelihood that valid data within the block is invalidated is registered for each of the blocks. The controller is configured to select a block to be a target of the compaction based on the first information and use the selected block to execute the compaction.
    Type: Grant
    Filed: March 7, 2014
    Date of Patent: April 5, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroki Matsudaira, Takashi Hirao, Aurelien Nam Phong Tran
  • Patent number: 9251055
    Abstract: A memory system in embodiments includes a nonvolatile semiconductor memory that stores user data, a forward lookup address translation table and a reverse lookup address translation table, and a controller. The controller is configured to determine that the user data stored in the nonvolatile semiconductor memory is valid or invalid based on these two tables. The controller may perform data organizing of selecting data determined valid and rewriting the data in a new block. The controller may perform write processing and rewriting processing to the new block alternately at a predetermined ratio. The controller may determine whether a predetermined condition is satisfied on a basis of addresses included in write requests and write data in the MLC mode when the condition is satisfied and write data in the SLC mode when the condition is not satisfied.
    Type: Grant
    Filed: August 30, 2012
    Date of Patent: February 2, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinji Yonezawa, Takashi Hirao, Hirokuni Yano, Mitsunori Tadokoro, Hiroki Matsudaira, Akira Sawaoka
  • Publication number: 20150340965
    Abstract: A semiconductor device is provided that can prevent a current from being concentrated into a specific chip, and can reduce loss as well as noise. The semiconductor device according to the present invention includes: a switching element; a main diode that is connected in parallel to the switching element; and an auxiliary diode that is connected in parallel to the switching element and has a different structure from that of the main diode, wherein in a conductive state a current flowing through the auxiliary diode is smaller than that through the main diode, and in a transition period from the conductive state to a non-conductive state a current flowing through the auxiliary diode is larger than that through the main diode.
    Type: Application
    Filed: May 22, 2015
    Publication date: November 26, 2015
    Inventors: Takashi HIRAO, Mutsuhiro MORI