Patents by Inventor Hirofumi Isomura

Hirofumi Isomura 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: 10666320
    Abstract: A ringing suppression circuit is provided at one or more nodes each having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines connected to the nodes. The circuit includes a suppression circuit and an operation mode controller: The suppression circuit is configured to execute a suppression operation for suppressing ringing in the differential signal. The operation mode controller is configured to set an operation mode of the suppression circuit to one of: a normal operation mode, which enables the suppression circuit to execute the suppression operation in response to detecting a change in a level of the differential signal, and a permanent off mode, which disables the suppression circuit to execute the suppression operation on a steady basis.
    Type: Grant
    Filed: November 27, 2018
    Date of Patent: May 26, 2020
    Assignee: DENSO CORPORATION
    Inventors: Takuya Honda, Hirofumi Isomura, Tomohisa Kishigami
  • Patent number: 10432188
    Abstract: A ringing suppression circuit connected to a transmission line to suppress ringing caused by the transmission line transmitting a differential signal using a pair of signal lines, the differential signal varying between a high level and a low level, the pair of signal lines including a high potential signal line and a low potential signal line, the ringing suppression circuit including: an inter-line switching element that is connected between the pair of signal lines; a control portion that performs a ringing suppression operation in response to detecting a level change in the differential signal, wherein the ringing suppression operation turns on the inter-line switching element to decrease an impedance between the pair of signal lines; and a suppression operation prohibiting portion that prohibits the control portion from performing the ringing suppression operation in response to detecting a signal caused by a signal on the transmission line.
    Type: Grant
    Filed: August 4, 2017
    Date of Patent: October 1, 2019
    Assignees: DENSO CORPORATION, SOKEN, INC.
    Inventors: Hiroyuki Mori, Takuya Honda, Tomohisa Kishigami, Hirofumi Isomura
  • Patent number: 10419071
    Abstract: A ringing suppression circuit is provided at a node having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines. The ringing suppression circuit includes: a suppressor configured to perform a suppression operation to suppress ringing occurred with a transmission of the differential signal by connecting a resistive component between the pair of communication lines; and a reference potential provider configured to provide a reference potential, which corresponds to a midpoint potential of the pair of communication lines during a steady state, to an intermediate point of the resistive component.
    Type: Grant
    Filed: January 21, 2019
    Date of Patent: September 17, 2019
    Assignee: DENSO CORPORATION
    Inventors: Takuya Honda, Hirofumi Isomura, Tomohisa Kishigami
  • Patent number: 10404495
    Abstract: A ringing suppression circuit is provided at one or more nodes each having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines connected to the nodes. The operation controller is configured to shift a mode of the suppressor to a normal-operation mode when the differential signal is transmitted through the pair of communication lines, and to shift the mode of the suppressor to a low-current operation mode when the differential signal is not transmitted through the pair of communication line. A current consumption of the suppressor is less in the low-current operation mode than the normal-operation mode. The suppressor and the operation controller are configured to receive permanent power from a DC power supply, and the communication circuit is configured to receive power from the DC power supply via a power supply switch.
    Type: Grant
    Filed: November 20, 2018
    Date of Patent: September 3, 2019
    Assignee: DENSO CORPORATION
    Inventor: Hirofumi Isomura
  • Publication number: 20190190516
    Abstract: A ringing suppression circuit connected to a transmission line to suppress ringing caused by the transmission line transmitting a differential signal using a pair of signal lines, the differential signal varying between a high level and a low level, the pair of signal lines including a high potential signal line and a low potential signal line, the ringing suppression circuit including: an inter-line switching element that is connected between the pair of signal lines; a control portion that performs a ringing suppression operation in response to detecting a level change in the differential signal, wherein the ringing suppression operation turns on the inter-line switching element to decrease an impedance between the pair of signal lines; and a suppression operation prohibiting portion that prohibits the control portion from performing the ringing suppression operation in response to detecting a signal caused by a signal on the transmission line.
    Type: Application
    Filed: August 4, 2017
    Publication date: June 20, 2019
    Inventors: Hiroyuki MORI, Takuya HONDA, Tomohisa KISHIGAMI, Hirofumi ISOMURA
  • Publication number: 20190158144
    Abstract: A ringing suppression circuit is provided at a node having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines. The ringing suppression circuit includes a suppressor configured to perform a suppression operation to suppress ringing occurred with a transmission of the differential signal by connecting an adjustment circuit between the pair of communication lines. The adjustment circuit includes a resistive component and a capacitive component connected in series.
    Type: Application
    Filed: January 21, 2019
    Publication date: May 23, 2019
    Inventors: Takuya HONDA, Hirofumi ISOMURA, Tomohisa KISHIGAMI
  • Publication number: 20190158143
    Abstract: A ringing suppression circuit is provided at a node having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines. The ringing suppression circuit includes: a suppressor configured to perform a suppression operation to suppress ringing occurred with a transmission of the differential signal by connecting a resistive component between the pair of communication lines; and a reference potential provider configured to provide a reference potential, which corresponds to a midpoint potential of the pair of communication lines during a steady state, to an intermediate point of the resistive component.
    Type: Application
    Filed: January 21, 2019
    Publication date: May 23, 2019
    Inventors: Takuya HONDA, Hirofumi ISOMURA, Tomohisa KISHIGAMI
  • Publication number: 20190097681
    Abstract: A ringing suppression circuit is provided at one or more nodes each having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines connected to the nodes. The circuit includes a suppression circuit and an operation mode controller: The suppression circuit is configured to execute a suppression operation for suppressing ringing in the differential signal. The operation mode controller is configured to set an operation mode of the suppression circuit to one of: a normal operation mode, which enables the suppression circuit to execute the suppression operation in response to detecting a change in a level of the differential signal, and a permanent off mode, which disables the suppression circuit to execute the suppression operation on a steady basis.
    Type: Application
    Filed: November 27, 2018
    Publication date: March 28, 2019
    Inventors: Takuya HONDA, Hirofumi ISOMURA, Tommohisa KISHIGAMI
  • Publication number: 20190089559
    Abstract: A ringing suppression circuit is provided at one or more nodes each having a communication circuit executing communication with another node by transmitting a differential signal through a pair of communication lines connected to the nodes. The operation controller is configured to shift a mode of the suppressor to a normal-operation mode when the differential signal is transmitted through the pair of communication lines, and to shift the mode of the suppressor to a low-current operation mode when the differential signal is not transmitted through the pair of communication line. A current consumption of the suppressor is less in the low-current operation mode than the normal-operation mode. The suppressor and the operation controller are configured to receive permanent power from a DC power supply, and the communication circuit is configured to receive power from the DC power supply via a power supply switch.
    Type: Application
    Filed: November 20, 2018
    Publication date: March 21, 2019
    Inventor: Hirofumi ISOMURA
  • Patent number: 10224925
    Abstract: A communication node is connected to a transmission line which transmits a differential signal changeable between a high level and a low level and has a high potential signal line and a low potential signal line as a pair of signal lines. The communication node includes: an inter-line potential detector that detects an intermediate potential between the pair of signal lines; a node potential detector that detects an intermediate potential of an operation power source voltage which is supplied to the communication node; and a voltage adjuster that detects a difference between the intermediate potential detected by the inter-line potential detector and the intermediate potential detected by the node potential detector, and adjusts the operation power source voltage in accordance with the difference.
    Type: Grant
    Filed: June 8, 2016
    Date of Patent: March 5, 2019
    Assignees: DENSO CORPORATION, SOKEN, INC.
    Inventors: Hiroyuki Mori, Takuya Honda, Tomohisa Kishigami, Hirofumi Isomura
  • Patent number: 10164620
    Abstract: A ringing suppression circuit, which is connected to a transmission line for transmitting a differential signal changeable between a high level and a low level in a binary level through a pair of a high potential side signal line and a low potential side signal line, and suppresses ringing that occurs in association with transmission of the differential signal, includes: an inter-line switching element that is connected to the pair of the high potential side signal line and the low potential side signal line; and a control unit that turns on the inter-line switching element and fixes an on state when detecting that the differential signal changes from the high level to the low level, and releases the on state after a predetermined time is measured and elapsed.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: December 25, 2018
    Assignees: DENSO CORPORATION, SOKEN, INC.
    Inventors: Takuya Honda, Hirofumi Isomura, Tomohisa Kishigami, Hiroyuki Mori, Yasuhiro Mori, Yuki Horii
  • Publication number: 20180367127
    Abstract: A ringing suppression circuit, which is connected to a transmission line for transmitting a differential signal changeable between a high level and a low level in a binary level through a pair of a high potential side signal line and a low potential side signal line, and suppresses ringing that occurs in association with transmission of the differential signal, includes: an inter-line switching element that is connected to the pair of the high potential side signal line and the low potential side signal line; and a control unit that turns on the inter-line switching element and fixes an on state when detecting that the differential signal changes from the high level to the low level, and releases the on state after a predetermined time is measured and elapsed.
    Type: Application
    Filed: August 25, 2016
    Publication date: December 20, 2018
    Inventors: Takuya HONDA, Hirofumi ISOMURA, Tomohisa KISHIGAMI, Hiroyuki MORI, Yasuhiro MORI, Yuki HORII
  • Patent number: 10128825
    Abstract: A ringing suppression circuit includes: a single line switching element, which is driven by a voltage, that is connected between a pair of signal lines; a controller that detects a change in a level of the differential signal and turns on the single line switching element to lower an impedance between the pair of signal lines; a period detector that detects a length of a suppressing period indicated by a setting signal, which is an input; and a suppressing period storage that stores the length of the suppressing period which is detected by the period detector. In addition, the pair of signal lines includes a high potential signal line and a low potential signal line. Moreover, the controller turns on the single line switching element for only the suppressing period having the length, which is stored in the suppressing period storage.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: November 13, 2018
    Assignees: DENSO CORPORATION, SOKEN, INC.
    Inventors: Hiroyuki Mori, Takuya Honda, Tomohisa Kishigami, Hirofumi Isomura
  • Publication number: 20180248542
    Abstract: A ringing suppression circuit includes: a single line switching element, which is driven by a voltage, that is connected between a pair of signal lines; a controller that detects a change in a level of the differential signal and turns on the single line switching element to lower an impedance between the pair of signal lines; a period detector that detects a length of a suppressing period indicated by a setting signal, which is an input; and a suppressing period storage that stores the length of the suppressing period which is detected by the period detector. In addition, the pair of signal lines includes a high potential signal line and a low potential signal line. Moreover, the controller turns on the single line switching element for only the suppressing period having the length, which is stored in the suppressing period storage.
    Type: Application
    Filed: August 25, 2016
    Publication date: August 30, 2018
    Inventors: Hiroyuki MORI, Takuya HONDA, Tomohisa KISHIGAMI, Hirofumi ISOMURA
  • Publication number: 20180198443
    Abstract: A communication node is connected to a transmission line which transmits a differential signal changeable between a high level and a low level and has a high potential signal line and a low potential signal line as a pair of signal lines. The communication node includes: an inter-line potential detector that detects an intermediate potential between the pair of signal lines; a node potential detector that detects an intermediate potential of an operation power source voltage which is supplied to the communication node; and a voltage adjuster that detects a difference between the intermediate potential detected by the inter-line potential detector and the intermediate potential detected by the node potential detector, and adjusts the operation power source voltage in accordance with the difference.
    Type: Application
    Filed: June 8, 2016
    Publication date: July 12, 2018
    Inventors: Hiroyuki MORI, Takuya HONDA, Tomohisa KISHIGAMI, Hirofumi ISOMURA
  • Patent number: 9660651
    Abstract: An input part is supplied with a low voltage from a low voltage power supply line. A level shift part and an output part are supplied with a high voltage from a high voltage power supply line. An input terminal is pulled up by a resistor and connected to the level shift part through a buffer circuit and an inverter circuit. The level shift part is connected in series with an NMOS and turned on when the input terminal changes to a low level. The output terminal is pulled up by a resistor through the buffer circuit. Even when the level shift part operates unstably because of long delay time from rising of a potential of the high voltage power supply line to rising of a potential of the low voltage power supply line, the output voltage is maintained at a high level.
    Type: Grant
    Filed: April 28, 2016
    Date of Patent: May 23, 2017
    Assignee: DENSO CORPORATION
    Inventors: Takuya Honda, Hirofumi Isomura
  • Publication number: 20170019090
    Abstract: An input part is supplied with a low voltage from a low voltage power supply line. A level shift part and an output part are supplied with a high voltage from a high voltage power supply line. An input terminal is pulled up by a resistor and connected to the level shift part through a buffer circuit and an inverter circuit. The level shift part is connected in series with an NMOS and turned on when the input terminal changes to a low level. The output terminal is pulled up by a resistor through the buffer circuit. Even when the level shift part operates unstably because of long delay time from rising of a potential of the high voltage power supply line to rising of a potential of the low voltage power supply line, the output voltage is maintained at a high level.
    Type: Application
    Filed: April 28, 2016
    Publication date: January 19, 2017
    Inventors: Takuya HONDA, Hirofumi ISOMURA
  • Patent number: 8451091
    Abstract: The present invention provides, as one aspect, a control system having sensor units and an electronic control unit. The electronic control unit includes a transmission controlling means which sets a signal line connected to the sensor unit, which is a destination of communication data, to a first state, sets the signal line connected to the sensor unit, which is not the destination, to a second state, and transmits the communication data to the destination via a communication line. The sensor unit includes a reception controlling means which determines a state of the signal line connecting a sensor to the electronic control unit. When determining that the signal line of the sensor unit is in the first state, the reception controlling means receives the communication data and performs a predetermined process. When determining that the signal line is in the second state, the reception controlling means discards the communication data.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: May 28, 2013
    Assignee: Denso Corporation
    Inventors: Toshikazu Hioki, Takeshi Iwai, Housyo Yukawa, Fumitaka Sugimoto, Hirofumi Isomura
  • Publication number: 20100161080
    Abstract: The present invention provides, as one aspect, a control system having sensor units and an electronic control unit. The electronic control unit includes a transmission controlling means which sets a signal line connected to the sensor unit, which is a destination of communication data, to a first state, sets the signal line connected to the sensor unit, which is not the destination, to a second state, and transmits the communication data to the destination via a communication line. The sensor unit includes a reception controlling means which determines a to state of the signal line connecting a sensor to the electronic control unit. When determining that the signal line of the sensor unit is in the first state, the reception controlling means receives the communication data and performs a predetermined process. When determining that the signal line is in the second state, the reception controlling means discards the communication data.
    Type: Application
    Filed: December 15, 2009
    Publication date: June 24, 2010
    Applicant: DENSO CORPORATION
    Inventors: Toshikazu HIOKI, Takeshi Iwai, Housyo Yukawa, Fumitaka Sugimoto, Hirofumi Isomura
  • Publication number: 20080197910
    Abstract: An input processing circuit implemented on a semiconductor integrated circuit includes an input terminal for receiving an input signal, a first diode coupled between the input terminal and a power line, a second diode coupled between the input terminal and a ground line, a first MOSFET having a gate and drain coupled together to the input terminal, and a source coupled to the ground line, a second MOSFET coupled to the first MOSFET to construct a current mirror circuit, a current-to-voltage conversion circuit coupled between the power line and the second MOSFET to convert an electric current flowing through the second MOSFET to a voltage, and a determination circuit configured to determine a state of the input signal based on a level of the output voltage of the current-to-voltage conversion circuit.
    Type: Application
    Filed: February 12, 2008
    Publication date: August 21, 2008
    Applicant: DENSO CORPORATION
    Inventor: Hirofumi Isomura