Patents by Inventor Takahisa Koyasu

Takahisa Koyasu 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: 11451202
    Abstract: A signal output circuit includes an inverting amplifier circuit, a feedback capacitor and a low pass filter. The inverting amplifier circuit includes an input terminal and an output terminal. The inverting amplifier circuit executes an inverting amplification based on an input signal to output a signal to the output terminal at a pull-up state. An output stage of the inverting amplifier circuit is an open collector or an open drain. The feedback capacitor is connected between the input terminal and the output terminal of the inverting amplifier circuit. The low pass filter has an input and an output. The input of the low pass filter is connected to the output terminal of the inverting amplifier. The output of the low pass filter is connected to the feedback capacitor.
    Type: Grant
    Filed: December 22, 2020
    Date of Patent: September 20, 2022
    Assignee: DENSO CORPORATION
    Inventor: Takahisa Koyasu
  • Publication number: 20210111682
    Abstract: A signal output circuit includes an inverting amplifier circuit, a feedback capacitor and a low pass filter. The inverting amplifier circuit includes an input terminal and an output terminal. The inverting amplifier circuit executes an inverting amplification based on an input signal to output a signal to the output terminal at a pull-up state. An output stage of the inverting amplifier circuit is an open collector or an open drain. The feedback capacitor is connected between the input terminal and the output terminal of the inverting amplifier circuit. The low pass filter has an input and an output. The input of the low pass filter is connected to the output terminal of the inverting amplifier. The output of the low pass filter is connected to the feedback capacitor.
    Type: Application
    Filed: December 22, 2020
    Publication date: April 15, 2021
    Inventor: Takahisa Koyasu
  • Patent number: 10056752
    Abstract: A rotary electric machine for a vehicle is provided. The rotary electric machine includes a power system circuit which has a power element and is grounded via a first ground terminal and a first connecting line and a control system circuit which controls the power system circuit and is grounded via a second ground terminal and a second connecting line.
    Type: Grant
    Filed: May 9, 2014
    Date of Patent: August 21, 2018
    Assignee: DENSO CORPORATION
    Inventors: Harumi Horihata, Tadatoshi Asada, Takahisa Koyasu
  • Patent number: 9948285
    Abstract: A drive control device includes: an input unit of a command; and a control unit setting a period for rising a current in an inductive load to first and third periods in first and second commands, and setting a period for falling the current to second and fourth periods in the first and second commands, respectively. When the first command is changed to the second command, and at least one middle PMW pulse is disposed between a forward PWM pulse corresponding to the first command and an after PWM pulse corresponding to the second command, the control unit sets fifth and sixth periods in the middle PWM pulse corresponding to the first and second periods of the forward PWM pulse to a length between the first and second periods in the forward PWM pulse and the third and fourth periods in the after PWM pulse, respectively.
    Type: Grant
    Filed: February 17, 2016
    Date of Patent: April 17, 2018
    Assignee: DENSO CORPORATION
    Inventors: Takahisa Koyasu, Yasuyuki Maeda
  • Publication number: 20160269015
    Abstract: A drive control device includes: an input unit of a command; and a control unit setting a period for rising a current in an inductive load to first and third periods in first and second commands, and setting a period for falling the current to second and fourth periods in the first and second commands, respectively. When the first command is changed to the second command, and at least one middle PMW pulse is disposed between a forward PWM pulse corresponding to the first command and an after PWM pulse corresponding to the second command, the control unit sets fifth and sixth periods in the middle PWM pulse corresponding to the first and second periods of the forward PWM pulse to a length between the first and second periods in the forward PWM pulse and the third and fourth periods in the after PWM pulse, respectively.
    Type: Application
    Filed: February 17, 2016
    Publication date: September 15, 2016
    Inventors: Takahisa KOYASU, Yasuyuki MAEDA
  • Patent number: 9106459
    Abstract: A communication circuit apparatus includes: multiple level shift circuits, each of which receives an input signal corresponding to a respective communication bus; an activation comparator for generating an activation signal when the input signal is input into one of the level shift circuits, and a level of the input signal exceeds a predetermined threshold; multiple input current voltage conversion circuits, each of which is arranged together with a respective level shift circuit, converts the input signal to a voltage signal, and outputs the voltage signal as an identification signal; and an identification circuit for identifying one of the communication busses based on the identification signal, which is output from one of the input current voltage conversion circuits. The one of the communication busses corresponds to the one of the level shift circuits, in which the input signal is input.
    Type: Grant
    Filed: July 2, 2014
    Date of Patent: August 11, 2015
    Assignee: DENSO CORPORATION
    Inventor: Takahisa Koyasu
  • Publication number: 20150035565
    Abstract: A communication circuit apparatus includes: multiple level shift circuits, each of which receives an input signal corresponding to a respective communication bus; an activation comparator for generating an activation signal when the input signal is input into one of the level shift circuits, and a level of the input signal exceeds a predetermined threshold; multiple input current voltage conversion circuits, each of which is arranged together with a respective level shift circuit, converts the input signal to a voltage signal, and outputs the voltage signal as an identification signal; and an identification circuit for identifying one of the communication busses based on the identification signal, which is output from one of the input current voltage conversion circuits. The one of the communication busses corresponds to the one of the level shift circuits, in which the input signal is input.
    Type: Application
    Filed: July 2, 2014
    Publication date: February 5, 2015
    Inventor: Takahisa KOYASU
  • Publication number: 20140334044
    Abstract: A rotary electric machine for a vehicle is provided. The rotary electric machine includes a power system circuit which has a power element and is grounded via a first ground terminal and a first connecting line and a control system circuit which controls the power system circuit and is grounded via a second ground terminal and a second connecting line.
    Type: Application
    Filed: May 9, 2014
    Publication date: November 13, 2014
    Inventors: Harumi HORIHATA, Tadatoshi ASADA, Takahisa KOYASU
  • Patent number: 8598919
    Abstract: A MOSFET at an input side controls the operation of a current mirror circuit in accordance with a level change of a PWM signal applied to its gate. When the current mirror circuit operates, a current generated by a current source flows as a mirror current so that a current flows to discharge electricity charged in a capacitance between a gate and a source through a gate of a MOSFET at an output side. When the current mirror circuit stops its operation, a current flowing from the current mirror circuit through the current source is supplied to the gate of the MOSFET at the output side.
    Type: Grant
    Filed: December 9, 2010
    Date of Patent: December 3, 2013
    Assignee: DENSO CORPORATION
    Inventor: Takahisa Koyasu
  • Patent number: 8598918
    Abstract: When a transmission signal is detected as having been changed from a high level to a low level, two transmission lines are connected for only a predetermined time through a diode by a first transistor and a second transistor. The diode is arranged such that its forward direction is from a high-side transmission line to a low-side transmission line. The diode turns on, when a potential of the high-side transmission line becomes higher than that of the low-side transmission line by ringing and a potential difference therebetween exceeds a forward drop voltage of the diode. As a result, a peak wave level of a positive side in the ringing is limited to the forward drop voltage of the diode.
    Type: Grant
    Filed: April 29, 2011
    Date of Patent: December 3, 2013
    Assignees: Nippon Soken, Inc., DENSO CORPORATION
    Inventors: Youichirou Suzuki, Noboru Maeda, Yasuhiro Fukagawa, Takahisa Koyasu, Masakiyo Horie, Tomohisa Kishigami
  • Patent number: 8320471
    Abstract: In a transmission device for differential communication, a first cathode-side element part is coupled between a first communication line and a cathode-side power supply line, a second cathode-side element part is coupled between a second communication line and the cathode-side power supply line, a first anode-side element part is coupled between the first communication line and an anode-side power supply line, and a second anode-side element part is coupled between the second communication line and the anode-side power supply line. A driving portion drives the element parts based on transmission data input from an outside. A target potential generating portion generates target potentials of the element parts based on potentials of the first communication line and the second communication line.
    Type: Grant
    Filed: September 20, 2010
    Date of Patent: November 27, 2012
    Assignees: DENSO CORPORATION, Nippon Soken, Inc.
    Inventors: Noboru Maeda, Youichirou Suzuki, Shigeki Takahashi, Kazuyoshi Nagase, Takahisa Koyasu
  • Patent number: 8229032
    Abstract: A signal receiver includes: a receiving circuit that receives a differential signal via a transmission line, which includes a pair of signal wires for transmitting the differential signal; and an impedance control circuit that controls an input impedance so as to reduce a common mode noise. The impedance control circuit includes a detection element for detecting at least one of a voltage, a current and an electric power of the common mode noise. The impedance control circuit controls the input impedance in accordance with change of the at least one of the voltages the current and the electric power of the common mode noise.
    Type: Grant
    Filed: February 20, 2009
    Date of Patent: July 24, 2012
    Assignees: DENSO CORPORATION, Nippon Soken, Inc.
    Inventors: Youichirou Suzuki, Noboru Maeda, Shigeki Takahashi, Koji Kondo, Kazuyoshi Nagase, Takahisa Koyasu
  • Patent number: 8160531
    Abstract: A receiving device is provided capable of avoiding reception of unnecessary energy when a signal waveform actually changes on a receiving side. An impedance control circuit includes a sensing unit to sense one or more of a voltage, current, or power of a signal to be received by a receiving circuit. The impedance control unit varies an input impedance according to the change in the sensed one or more quantities so that the received signal will be reflected. Thus the excess energy of the signal is reflected and fed to any other receiving circuit achieving stable communications.
    Type: Grant
    Filed: March 10, 2009
    Date of Patent: April 17, 2012
    Assignees: Nippon Soken, Inc., Denso Corporation
    Inventors: Youichirou Suzuki, Noboru Maeda, Takahisa Koyasu, Koji Kondo, Shigeki Takahashi
  • Patent number: 8098084
    Abstract: A transmission apparatus for differential communication includes a driver bridge circuit and a pair of noise protection circuits. The driver bridge circuit includes four output devices that are independently connected between each of a pair of transmission lines and a power line or a ground line. Each noise protection circuit is provided to a corresponding transmission lines. Each noise protection circuit includes a ground potential detector and an impedance controller. The ground potential detector detects a potential of the corresponding transmission line with respect to the ground line. The impedance controller causes an impedance of the corresponding transmission line with respect to the ground line to become equal to an impedance of the other transmission line with respect to the ground line, when the detected potential becomes outside a predetermined potential range.
    Type: Grant
    Filed: October 12, 2010
    Date of Patent: January 17, 2012
    Assignees: Nippon Soken, Inc., Denso Corporation
    Inventors: Youichirou Suzuki, Noboru Maeda, Shigeki Takahashi, Takahisa Koyasu, Kazuyoshi Nagase, Tomohisa Kishigami
  • Publication number: 20110285424
    Abstract: When a transmission signal is detected as having been changed from a high level to a low level, two transmission lines are connected for only a predetermined time through a diode by a first transistor and a second transistor. The diode is arranged such that its forward direction is from a high-side transmission line to a low-side transmission line. The diode turns on, when a potential of the high-side transmission line becomes higher than that of the low-side transmission line by ringing and a potential difference therebetween exceeds a forward drop voltage of the diode. As a result, a peak wave level of a positive side in the ringing is limited to the forward drop voltage of the diode.
    Type: Application
    Filed: April 29, 2011
    Publication date: November 24, 2011
    Applicants: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Youichirou Suzuki, Noboru Maeda, Yasuhiro Fukagawa, Takahisa Koyasu, Masakiyo Horie, Tomohisa Kishigami
  • Publication number: 20110169475
    Abstract: A MOSFET at an input side controls the operation of a current mirror circuit in accordance with a level change of a PWM signal applied to its gate. When the current mirror circuit operates, a current generated by a current source flows as a mirror current so that a current flows to discharge electricity charged in a capacitance between a gate and a source through a gate of a MOSFET at an output side. When the current mirror circuit stops its operation, a current flowing from the current mirror circuit through the current source is supplied to the gate of the MOSFET at the output side.
    Type: Application
    Filed: December 9, 2010
    Publication date: July 14, 2011
    Applicant: DENSO CORPORATION
    Inventor: Takahisa KOYASU
  • Publication number: 20110135014
    Abstract: In a transmission device for differential communication, a first cathode-side element part is coupled between a first communication line and a cathode-side power supply line, a second cathode-side element part is coupled between a second communication line and the cathode-side power supply line, a first anode-side element part is coupled between the first communication line and an anode-side power supply line, and a second anode-side element part is coupled between the second communication line and the anode-side power supply line. A driving portion drives the element parts based on transmission data input from an outside. A target potential generating portion generates target potentials of the element parts based on potentials of the first communication line and the second communication line.
    Type: Application
    Filed: September 20, 2010
    Publication date: June 9, 2011
    Applicants: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Noboru Maeda, Youichirou Suzuki, Shigeki Takahashi, Kazuyoshi Nagase, Takahisa Koyasu
  • Publication number: 20110084730
    Abstract: A transmission apparatus for differential communication includes a driver bridge circuit and a pair of noise protection circuits. The driver bridge circuit includes four output devices that are independently connected between each of a pair of transmission lines and a power line or a ground line. Each noise protection circuit is provided to a corresponding transmission lines. Each noise protection circuit includes a ground potential detector and an impedance controller. The ground potential detector detects a potential of the corresponding transmission line with respect to the ground line. The impedance controller causes an impedance of the corresponding transmission line with respect to the ground line to become equal to an impedance of the other transmission line with respect to the ground line, when the detected potential becomes outside a predetermined potential range.
    Type: Application
    Filed: October 12, 2010
    Publication date: April 14, 2011
    Applicants: NIPPON SOKEN, INC., DENSO CORPORATION
    Inventors: Youichirou SUZUKI, Noboru MAEDA, Shigeki TAKAHASHI, Takahisa KOYASU, Kazuyoshi NAGASE, Tomohisa KISHIGAMI
  • Publication number: 20090296830
    Abstract: A signal receiver includes: a receiving circuit that receives a differential signal via a transmission line, which includes a pair of signal wires for transmitting the differential signal; and an impedance control circuit that controls an input impedance so as to reduce a common mode noise. The impedance control circuit includes a detection element for detecting at least one of a voltage, a current and an electric power of the common mode noise. The impedance control circuit controls the input impedance in accordance with change of the at least one of the voltages the current and the electric power of the common mode noise.
    Type: Application
    Filed: February 20, 2009
    Publication date: December 3, 2009
    Applicants: DENSO CORPORATION, NIPPON SOKEN, INC.
    Inventors: Youichirou SUZUKI, Noboru MAEDA, Shigeki TAKAHASHI, Koji KONDO, Kazuyoshi NAGASE, Takahisa KOYASU
  • Publication number: 20090233565
    Abstract: A receiving device is provided capable of avoiding reception of unnecessary energy when a signal waveform actually changes on a receiving side. An impedance control circuit includes a sensing unit to sense one or more of a voltage, current, or power of a signal to be received by a receiving circuit. The impedance control unit varies an input impedance according to the change in the sensed one or more quantities so that the received signal will be reflected. Thus the excess energy of the signal is reflected and fed to any other receiving circuit achieving stable communications.
    Type: Application
    Filed: March 10, 2009
    Publication date: September 17, 2009
    Applicants: NIPPON SOKEN, INC, DENSO CORPORATION
    Inventors: Youichirou Suzki, Noboru Maeda, Takahisa Koyasu, Koji Kondo, Shigeki Takahashi