Patents by Inventor Hideyuki Tajima

Hideyuki Tajima 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: 20240146293
    Abstract: A semiconductor device that outputs a high-speed and large-current pulse is provided. The semiconductor device includes: a first N channel transistor having its gate receiving a second voltage as its input; a first resistance element having its second terminal connected to a drain of the first N channel transistor; a second resistance element having its first terminal connected to a source of the first N channel transistor; a second N channel transistor having its gate receiving a second voltage as its input; a third resistance element having its second terminal connected to a drain of the second N channel transistor; a fourth resistance element having its first terminal connected to a source of the second N channel transistor; and an isolator having its first terminal connected to the drain of the first N channel transistor and having its second terminal connected to the drain of the second N channel transistor.
    Type: Application
    Filed: September 20, 2023
    Publication date: May 2, 2024
    Inventors: Noboru INOMATA, Hideyuki TAJIMA
  • Publication number: 20230198378
    Abstract: A semiconductor device includes: a constant current generating circuit unit; a first current mirror circuit unit having a constant current as an input current and generating a first mirror current as a mirror current; a level shift circuit unit including a clamp transistor between whose drain and source a first mirror current flows and to whose base a power supply voltage of the constant current generating circuit unit is applied, and a transistor that is connected in series to the clamp transistor and through which the first mirror current flows; a second current mirror circuit unit having as an input stage a transistor and having as an output stage a transistor through which a second mirror current replicating the first mirror current flows; and an error absorption circuit unit connected to a terminal for outputting the second mirror current of the output-stage transistor in the second current mirror circuit unit.
    Type: Application
    Filed: December 22, 2022
    Publication date: June 22, 2023
    Applicant: Renesas Electronics Corporation
    Inventor: Hideyuki TAJIMA
  • Patent number: 11575319
    Abstract: A DC-DC converter includes a high-side switch coupled between a first power supply and an output terminal, a low-side switch coupled between a second power supply and the output terminal, an inductor coupled to the output terminal, and a reverse current monitoring circuit that determines that a reverse current from the inductor to the output terminal occurs when the output terminal becomes a high voltage during a state in which the high-side switch and the low-side switch are in a dead time.
    Type: Grant
    Filed: December 30, 2020
    Date of Patent: February 7, 2023
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Masayuki Ida, Yasuhiko Kokami, Hideyuki Tajima, Hiroyuki Inoue, Noboru Inomata
  • Patent number: 11385266
    Abstract: The present invention provides a current detection circuit, semiconductor device, and a semiconductor system suitable for improving a current sensing accuracy. According to one embodiment, the current detection circuit 12 comprises a sense transistor Tr11 through which a first sense current proportional to the current flowing through the drive transistor MN1 flows, an operational amplifier AMP1 for amplifying the potential difference of the voltage of the external output terminal OUT and the source voltage of the sense transistor Tr11 for outputting the first sense current, a transistor Tr12 provided in series with the sense transistor Tr11 and to which the output voltage of the operational amplifier AMP1 is applied to the gate, and a switch SW3 provided between the external output terminal OUT and the source of the sense transistor Tr11 and turned on when the drive transistor MN1 is turned off.
    Type: Grant
    Filed: March 16, 2020
    Date of Patent: July 12, 2022
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Keisuke Kimura, Hideyuki Tajima, Wataru Saito
  • Patent number: 11171086
    Abstract: A semiconductor device includes a base member, a multilayer wiring layer, and a first resistive element. The multilayer wiring layer is formed on the base member. The first resistive element is formed in the multilayer wiring layer. The first resistive element includes a first conductive part, a second conductive part and a third conductive part. The second conductive part is formed over the first conductive part. The third conductive part electrically connects the first conductive part and the second conductive part with each other. A length of the third conductive part in a first direction along a surface of the base member is greater than a length of the third conductive part in a second direction along the surface of the base member and perpendicular to the first direction.
    Type: Grant
    Filed: December 2, 2019
    Date of Patent: November 9, 2021
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Shunji Kubo, Koichi Ando, Eiji Io, Hideyuki Tajima, Tetsuya Iida
  • Publication number: 20210249958
    Abstract: A DC-DC converter includes a high-side switch coupled between a first power supply and an output terminal, a low-side switch coupled between a second power supply and the output terminal, an inductor coupled to the output terminal, and a reverse current monitoring circuit that determines that a reverse current from the inductor to the output terminal occurs when the output terminal becomes a high voltage during a state in which the high-side switch and the low-side switch are in a dead time.
    Type: Application
    Filed: December 30, 2020
    Publication date: August 12, 2021
    Inventors: Masayuki IDA, Yasuhiko KOKAMI, Hideyuki TAJIMA, Hiroyuki INOUE, Noboru INOMATA
  • Publication number: 20210167012
    Abstract: A semiconductor device includes a base member, a multilayer wiring layer, and a first resistive element. The multilayer wiring layer is formed on the base member. The first resistive element is formed in the multilayer wiring layer. The first resistive element includes a first conductive part, a second conductive part and a third conductive part. The second conductive part is formed over the first conductive part. The third conductive part electrically connects the first conductive part and the second conductive part with each other. A length of the third conductive part in a first direction along a surface of the base member is greater than a length of the third conductive part in a second direction along the surface of the base member and perpendicular to the first direction.
    Type: Application
    Filed: December 2, 2019
    Publication date: June 3, 2021
    Inventors: Shunji KUBO, Koichi ANDO, Eiji IO, Hideyuki TAJIMA, Tetsuya IIDA
  • Patent number: 10855266
    Abstract: A monitor circuit monitors a gate potential applied to a gate of a high-side transistor or monitors an output potential generated at an output terminal and generates either one or both of a high-side sampling timing and a high-side holding timing based on the monitored result. A current detection circuit detects an inductor current flowing in an inductor and generates a first detection voltage proportional to the inductor current. A sample-and-hold circuit starts a sampling operation of the first detection voltage in response to the high-side sampling timing and starts a holding operation of the first detection voltage in response to the high-side holding timing so as to output a second detection voltage.
    Type: Grant
    Filed: December 18, 2018
    Date of Patent: December 1, 2020
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventor: Hideyuki Tajima
  • Publication number: 20200309824
    Abstract: The present invention provides a current detection circuit, semiconductor device, and a semiconductor system suitable for improving a current sensing accuracy. According to one embodiment, the current detection circuit 12 comprises a sense transistor Tr11 through which a first sense current proportional to the current flowing through the drive transistor MN1 flows, an operational amplifier AMP1 for amplifying the potential difference of the voltage of the external output terminal OUT and the source voltage of the sense transistor Tr11 for outputting the first sense current, a transistor Tr12 provided in series with the sense transistor Tr11 and to which the output voltage of the operational amplifier AMP1 is applied to the gate, and a switch SW3 provided between the external output terminal OUT and the source of the sense transistor Tr11 and turned on when the drive transistor MN1 is turned off.
    Type: Application
    Filed: March 16, 2020
    Publication date: October 1, 2020
    Inventors: Keisuke KIMURA, Hideyuki TAJIMA, Wataru SAITO
  • Patent number: 10620239
    Abstract: A semiconductor device includes: a drive transistor controlling current supply to a load; a current detector unit detecting a current of a sense transistor through which a current proportional to the current flowing through the drive transistor flows; a controller unit generating a pulse signal with a duty ratio corresponding to the detection result of the current detector unit; a voltage monitor monitoring whether a voltage of an external output terminal reaches a battery voltage; and a pre-driver performing charge and discharge to a control terminal of the drive transistor based on the pulse signal. The pre-driver performs the charge and discharge to the control terminal of the drive transistor at a first speed, when the voltage of the external output terminal reaches the battery voltage, and at a speed faster than the first speed, when the voltage of the external output terminal reaches the battery voltage.
    Type: Grant
    Filed: January 17, 2019
    Date of Patent: April 14, 2020
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventor: Hideyuki Tajima
  • Patent number: 10454465
    Abstract: In one semiconductor chip, driving transistors, a current sensor, and a temperature sensor for sensing a temperature of a driver area are arranged in a driver area, and a current sensing circuit, an analog-digital converter, and a temperature sensor for sensing a peripheral circuit area are arranged in a peripheral circuit area. A correction circuit unit corrects a digital sensed voltage from the analog-digital converter based on a sensing result of the temperature sensor of the driver area and a sensed result of the temperature sensor of the peripheral circuit area.
    Type: Grant
    Filed: December 18, 2018
    Date of Patent: October 22, 2019
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventor: Hideyuki Tajima
  • Publication number: 20190265744
    Abstract: A semiconductor device includes: a drive transistor controlling current supply to a load; a current detector unit detecting a current of a sense transistor through which a current proportional to the current flowing through the drive transistor flows; a controller unit generating a pulse signal with a duty ratio corresponding to the detection result of the current detector unit; a voltage monitor monitoring whether a voltage of an external output terminal reaches a battery voltage; and a pre-driver performing charge and discharge to a control terminal of the drive transistor based on the pulse signal. The pre-driver performs the charge and discharge to the control terminal of the drive transistor at a first speed, when the voltage of the external output terminal reaches the battery voltage, and at a speed faster than the first speed, when the voltage of the external output terminal reaches the battery voltage.
    Type: Application
    Filed: January 17, 2019
    Publication date: August 29, 2019
    Inventor: Hideyuki TAJIMA
  • Publication number: 20190260292
    Abstract: According to an embodiment, a current detection circuit includes a transistor, an operational amplifier, and a transistor. In the transistor, the source and the gate are coupled to the source and the gate of a transistor which is provided on a high side of a drive circuit. The operational amplifier amplifies a potential difference between a drain voltage of the transistor and a drain voltage of the transistor. The transistor is provided over a current path through which a current flowing to the transistor flows, and which has the gate to which an output voltage of the operational amplifier is supplied. A value of the current flowing through the transistor is detected based on a value of the current flowing through the transistor.
    Type: Application
    Filed: February 15, 2019
    Publication date: August 22, 2019
    Inventor: Hideyuki TAJIMA
  • Publication number: 20190238124
    Abstract: In one semiconductor chip, driving transistors, a current sensor, and a temperature sensor for sensing a temperature of a driver area are arranged in a driver area, and a current sensing circuit, an analog-digital converter, and a temperature sensor for sensing a peripheral circuit area are arranged in a peripheral circuit area. A correction circuit unit corrects a digital sensed voltage from the analog-digital converter based on a sensing result of the temperature sensor of the driver area and a sensed result of the temperature sensor of the peripheral circuit area.
    Type: Application
    Filed: December 18, 2018
    Publication date: August 1, 2019
    Inventor: Hideyuki TAJIMA
  • Publication number: 20190229717
    Abstract: A monitor circuit monitors a gate potential applied to a gate of a high-side transistor or monitors an output potential generated at an output terminal and generates either one or both of a high-side sampling timing and a high-side holding timing based on the monitored result. A current detection circuit detects an inductor current flowing in an inductor and generates a first detection voltage proportional to the inductor current. A sample-and-hold circuit starts a sampling operation of the first detection voltage in response to the high-side sampling timing and starts a holding operation of the first detection voltage in response to the high-side holding timing so as to output a second detection voltage.
    Type: Application
    Filed: December 18, 2018
    Publication date: July 25, 2019
    Inventor: Hideyuki TAJIMA
  • Patent number: 10256725
    Abstract: According to an embodiment, a current detection circuit includes a transistor, an operational amplifier, and a transistor. In the transistor, the source and the gate are coupled to the source and the gate of a transistor which is provided on a high side of a drive circuit. The operational amplifier amplifies a potential difference between a drain voltage of the transistor and a drain voltage of the transistor. The transistor is provided over a current path through which a current flowing to the transistor flows, and which has the gate to which an output voltage of the operational amplifier is supplied. A value of the current flowing through the transistor is detected based on a value of the current flowing through the transistor.
    Type: Grant
    Filed: March 17, 2017
    Date of Patent: April 9, 2019
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventor: Hideyuki Tajima
  • Publication number: 20170279357
    Abstract: According to an embodiment, a current detection circuit includes a transistor, an operational amplifier, and a transistor. In the transistor, the source and the gate are coupled to the source and the gate of a transistor which is provided on a high side of a drive circuit. The operational amplifier amplifies a potential difference between a drain voltage of the transistor and a drain voltage of the transistor. The transistor is provided over a current path through which a current flowing to the transistor flows, and which has the gate to which an output voltage of the operational amplifier is supplied. A value of the current flowing Through The transistor is detected based on a value of the current flowing through the transistor.
    Type: Application
    Filed: March 17, 2017
    Publication date: September 28, 2017
    Inventor: Hideyuki TAJIMA
  • Publication number: 20170222558
    Abstract: According to one embodiment, a DC-DC converter 1 includes a power supply unit 12 that includes an inductor L1 and a switching unit and generates an output voltage Vout corresponding to a duty of a pulse signal P1, a PID controller 111 that outputs a control signal S corresponding to a difference between a divided voltage of Vout and a target voltage Vcnst, a PI controller 112 that outputs a control signal D corresponding to a difference between the control signal S and an average current flowing through the inductor L1, a PWM generation unit 113 that generates the pulse signal P1 with a duty ratio corresponding to the control signal D, and in step-down mode, the PI controller 112 performs proportional control of the differential signal ei by using a product of the control signal D and a reference proportionality constant KP as a proportionality constant.
    Type: Application
    Filed: April 18, 2017
    Publication date: August 3, 2017
    Applicant: Renesas Electronics Corporation
    Inventor: Hideyuki TAJIMA
  • Patent number: 9654006
    Abstract: According to one embodiment, a DC-DC converter 1 includes a power supply unit 12 that includes an inductor L1 and a switching unit and generates an output voltage Vout corresponding to a duty of a pulse signal P1, a PID controller 111 that outputs a control signal S corresponding to a difference between a divided voltage of Vout and a target voltage Vcnst, a PI controller 112 that outputs a control signal D corresponding to a difference between the control signal S and an average current flowing through the inductor L1, a PWM generation unit 113 that generates the pulse signal P1 with a duty ratio corresponding to the control signal D, and in step-down mode, the PI controller 112 performs proportional control of the differential signal ei by using a product of the control signal D and a reference proportionality constant KP as a proportionality constant.
    Type: Grant
    Filed: January 8, 2016
    Date of Patent: May 16, 2017
    Assignee: Renesas Electronics Corporation
    Inventor: Hideyuki Tajima
  • Publication number: 20160248325
    Abstract: According to one embodiment, a DC-DC converter 1 includes a power supply unit 12 that includes an inductor L1 and a switching unit and generates an output voltage Vout corresponding to a duty of a pulse signal P1, a PID controller 111 that outputs a control signal S corresponding to a difference between a divided voltage of Vout and a target voltage Vcnst, a PI controller 112 that outputs a control signal D corresponding to a difference between the control signal S and an average current flowing through the inductor L1, a PWM generation unit 113 that generates the pulse signal P1 with a duty ratio corresponding to the control signal D, and in step-down mode, the PI controller 112 performs proportional control of the differential signal ei by using a product of the control signal D and a reference proportionality constant KP as a proportionality constant.
    Type: Application
    Filed: January 8, 2016
    Publication date: August 25, 2016
    Applicant: Renesas Electronics Corporation
    Inventor: Hideyuki Tajima