Patents by Inventor Naoki ITABASHI

Naoki ITABASHI 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: 11362629
    Abstract: A transimpedance amplifier (TIA) circuit disclosed includes an input terminal, a first TIA circuit, a second TIA circuit, a field effect transistor (FET), and a gain control circuit. The first TIA circuit outputs a voltage signal from a first output in accordance with an input current received at a first input electrically connected to the input terminal. The second TIA circuit outputs a reference signal from a second output. The FET varies a resistance between a first current terminal and a second current terminal in accordance with a control signal applied to a control terminal. The first current terminal is electrically connected to the input terminal. The second current terminal is electrically connected to the second output of the second TIA circuit. The gain control circuit detects an amplitude of the voltage signal and generates the control signal according to a detection result of the amplitude.
    Type: Grant
    Filed: October 14, 2020
    Date of Patent: June 14, 2022
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Naoki Itabashi, Keiji Tanaka
  • Publication number: 20220149592
    Abstract: An optical semiconductor module according to the embodiment includes: a board including a transmission line; a block including a low-permittivity material; an inductor mounted on the block, the inductor being connected with the transmission line via a first wire, the first wire having a first inductance; a semiconductor laser device mounted on the board, the semiconductor laser device being connected with the transmission line via a second wire, the second wire having a second inductance smaller than the first inductance; and a housing configured to accommodate the board, the block, the inductor, and the semiconductor laser device.
    Type: Application
    Filed: November 8, 2021
    Publication date: May 12, 2022
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Naoki ITABASHI
  • Publication number: 20220149590
    Abstract: An optical semiconductor module according to an embodiment includes a housing; a temperature control element having a temperature control plane; a first board mounted on the temperature control plane; a semiconductor laser device mounted on the second side of the first board; a second board mounted on the second side of the first board, the second board having a third side and a fourth side, the fourth side including a wiring pattern, the wiring pattern being electrically connected with the housing via a first bonding wire and electrically connected to the semiconductor laser device via a second bonding wire, the second board having a second thermal conductivity smaller than the first thermal conductivity. The housing is configured to accommodate the temperature control element, the first board, the second board, and the semiconductor laser device.
    Type: Application
    Filed: November 8, 2021
    Publication date: May 12, 2022
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Naoki ITABASHI
  • Publication number: 20220085568
    Abstract: A light semiconductor device according to an embodiment includes: a carrier having a first pattern for transmitting a signal and a second pattern having a reference potential constituting a coplanar line together with the first pattern on a front surface; a modulator having a first electrode provided on a back surface and connected to the second pattern of the carrier and a second electrode provided on a front surface and connected to the first pattern of the carrier; and a first connection portion having one end connected to the second pattern of the carrier and the other end connected to the first electrode of the modulator. The front surface of the modulator and a front surface of the carrier face each other.
    Type: Application
    Filed: September 15, 2021
    Publication date: March 17, 2022
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Naoki ITABASHI, Hiroshi Hara
  • Publication number: 20210126604
    Abstract: A differential amplifier circuit disclosed includes a first transistor, a second transistor, a field effect transistor (FET) connected between the first transistor and the second transistor, a first current source connected to the first transistor, a second current source connected to the second transistor, and a control circuit. The first transistor and the second transistor generates a differential output signal in accordance with an input signal and a reference signal. The control circuit includes a first resistor and a second resistor connected in series to each other between drain and source of the FET, a center node between the first resistor and the second resistor, a third resistor connected between gate of the FET and the center node, and a variable current source. The variable current source supplies a control current to the third resistor in accordance with a gain control signal. The control circuit controls on-resistance of the FET.
    Type: Application
    Filed: October 22, 2020
    Publication date: April 29, 2021
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Naoki ITABASHI, Keiji TANAKA
  • Publication number: 20210126602
    Abstract: An optical receiver disclosed includes a bias terminal, an input terminal, a photodiode, an amplifier circuit, a first resistor, a bypass circuit, a filter circuit, and a control circuit. The photodiode receives a bias from the filter circuit through the bias terminal, and outputs a current signal to the amplifier circuit through the input terminal. The amplifier circuit converts an input current to an output voltage. The bypass circuit electrically connected to the input terminal decreases a first input impedance viewed from the input terminal, when activated, and increases the first input impedance, when deactivated. The filter circuit increases a second input impedance viewed from the bias terminal, when a dumping function thereof is activated, and decreases the second input impedance, when the dumping function is deactivated. The control circuit activates the dumping function and the bypass circuit, when the output voltage is larger than a certain voltage.
    Type: Application
    Filed: October 14, 2020
    Publication date: April 29, 2021
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Naoki ITABASHI, Keiji TANAKA
  • Publication number: 20210126603
    Abstract: A transimpedance amplifier (TIA) circuit disclosed includes an input terminal, a first TIA circuit, a second TIA circuit, a field effect transistor (FET), and a gain control circuit. The first TIA circuit outputs a voltage signal from a first output in accordance with an input current received at a first input electrically connected to the input terminal. The second TIA circuit outputs a reference signal from a second output. The FET varies a resistance between a first current terminal and a second current terminal in accordance with a control signal applied to a control terminal. The first current terminal is electrically connected to the input terminal. The second current terminal is electrically connected to the second output of the second TIA circuit. The gain control circuit detects an amplitude of the voltage signal and generates the control signal according to a detection result of the amplitude.
    Type: Application
    Filed: October 14, 2020
    Publication date: April 29, 2021
    Inventors: Naoki ITABASHI, Keiji TANAKA
  • Patent number: 10644653
    Abstract: An amplifier includes a printed circuit board that includes an output terminal for outputting an electrical signal to an outside and a bias terminal for receiving a bias of the electrical signal from the outside, and an integrated circuit, a capacitor, an inductor, and a ferrite bead element mounted on the printed circuit board. The integrated circuit includes a driving circuit and an output end, and outputs the electrical signal generated by the driving circuit from the output end. The capacitor is connected between the output end and the output terminal. A series circuit includes the inductor and the ferrite bead element connected to each other in series, with the inductor connected to the output end, and the ferrite bead element connected to the bias terminal.
    Type: Grant
    Filed: November 9, 2017
    Date of Patent: May 5, 2020
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Naoki Itabashi
  • Patent number: 10608599
    Abstract: A transimpedance amplifier includes a variable gain circuit configured to generate a pair of complementary signals in accordance with an input signal and a reference signal. A first differential circuit of the variable gain circuit includes a first transistor including a control terminal to receive the input signal, a second transistor including a control terminal to receive the reference signal, and a variable resistance circuit including a first field effect transistor (FET) and a second FET. A first timing when a voltage of a first linearity adjustment signal input to the first FET reaches a first threshold voltage of the first FET and a second timing when a voltage of a second linearity adjustment signal input to the second FET reaches a second threshold voltage of the second FET are different from each other.
    Type: Grant
    Filed: August 10, 2018
    Date of Patent: March 31, 2020
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Yoshiyuki Sugimoto, Naoki Itabashi
  • Patent number: 10574027
    Abstract: An LD driver circuit includes an adjustment circuit to which a power supply voltage is applied. The adjustment circuit receives an input signal through an input terminal, generates a shifted input signal shifted in voltage from the input signal by a predetermined shift amount, and outputs the shifted input signal from an output terminal. The LD driver circuit also includes a transistor with its base receiving the shifted input signal, its collector electrically connected to an anode of a driven LD, and its emitter electrically connected to a cathode of the LD and ground, which transistor varies an amount of a shunt current flowing from the collector to the emitter in accordance with the shifted input signal. The adjustment circuit includes a comparator which compares a voltage in the collector and a threshold voltage, and increases or decreases the predetermined shift amount in accordance with an output of the comparator.
    Type: Grant
    Filed: February 1, 2019
    Date of Patent: February 25, 2020
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Naoki Itabashi, Keiji Tanaka
  • Patent number: 10396719
    Abstract: A circuit device includes a differential circuit including differential input terminals; a differential amplifier circuit in which differential input nodes are connected to the differential input terminals; a first power supply terminal supplied with a first voltage; a second power supply terminal supplied with a second voltage; a common terminal; a first resistive element of which one end is connected to one differential input terminal and another end is connected to the common terminal; a second resistive element of which one end is connected to the first supply terminal and another end is connected to the common terminal; a third resistive element of which one end is connected to one differential input terminal and another end is connected to the second supply terminal; a bonding wire, and a capacitor of which one end is connected to the second supply terminal and another end is connected to the common terminal.
    Type: Grant
    Filed: May 24, 2018
    Date of Patent: August 27, 2019
    Assignee: Sumitomo Electric Industries, LTD
    Inventors: Naoki Itabashi, Taizo Tatsumi
  • Publication number: 20190245324
    Abstract: An LD driver circuit includes an adjustment circuit, to which a power supply voltage is applied, which receives an input signal through an input terminal, and which generates a shifted input signal shifted in voltage from the input signal by a predetermined shift amount and outputs the shifted input signal from an output terminal; and a transistor, in which a base receives the shifted input signal, in which a collector is electrically connected to an anode of an LD, in which an emitter is electrically connected to a cathode of the LD and a ground, and which varies an amount of a shunt current flowing the collector to the emitter in accordance with the shifted input signal. The adjustment circuit includes a comparator which compares a voltage in the collector and a threshold voltage, and increases or decreases the predetermined shift amount in accordance with an output of the comparator.
    Type: Application
    Filed: February 1, 2019
    Publication date: August 8, 2019
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Naoki Itabashi, Keiji Tanaka
  • Patent number: 10263583
    Abstract: A variable gain amplifier capable of stabilizing an average output potential of a differential output signal, improving power efficiency over a wide range of an amplitude of the differential input signal, and suppressing deterioration of a distortion rate is provided. The variable gain amplifier includes an amplifying circuit configured to amplify a differential input signal with a gain according to a gain control signal, and a current control circuit. The amplifying circuit has a first current source supplying a source current. The current control circuit adjusts a magnitude of the source current of the first current source according to a magnitude of the gain control signal.
    Type: Grant
    Filed: January 3, 2018
    Date of Patent: April 16, 2019
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Naoki Itabashi
  • Publication number: 20190052236
    Abstract: A transimpedance amplifier includes a variable gain circuit configured to generate a pair of complementary signals in accordance with an input signal and a reference signal. A first differential circuit of the variable gain circuit includes a first transistor including a control terminal to receive the input signal, a second transistor including a control terminal to receive the reference signal, and a variable resistance circuit including a first field effect transistor (FET) and a second FET. A first timing when a voltage of a first linearity adjustment signal input to the first FET reaches a first threshold voltage of the first FET and a second timing when a voltage of a second linearity adjustment signal input to the second FET reaches a second threshold voltage of the second FET are different from each other.
    Type: Application
    Filed: August 10, 2018
    Publication date: February 14, 2019
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Yoshiyuki SUGIMOTO, Naoki ITABASHI
  • Publication number: 20180342987
    Abstract: An circuit device includes a differential circuit including differential input terminals; a differential amplifier circuit in which differential input nodes are connected to the differential input terminals; a first power supply terminal applied a first voltage to; a second power supply terminal applied a second voltage to; a common terminal; a first resistive element of which one end is connected to one differential input terminal and another end is connected to the common terminal; a second resistive element of which one end is connected to the first supply terminal and another end is connected to the common terminal; a third resistive element of which one end is connected to one differential input terminal and another end is connected to the second supply terminal; a bonding wire, and a capacitor of which one end is connected to the second supply terminal and another end is connected to the common terminal
    Type: Application
    Filed: May 24, 2018
    Publication date: November 29, 2018
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD,
    Inventors: Naoki Itabashi, Taizo Tatsumi
  • Publication number: 20180198431
    Abstract: A variable gain amplifier capable of stabilizing an average output potential of a differential output signal, improving power efficiency over a wide range of an amplitude of the differential input signal, and suppressing deterioration of a distortion rate is provided. The variable gain amplifier includes an amplifying circuit configured to amplify a differential input signal with a gain according to a gain control signal, and a current control circuit. The amplifying circuit has a first current source supplying a source current. The current control circuit adjusts a magnitude of the source current of the first current source according to a magnitude of the gain control signal.
    Type: Application
    Filed: January 3, 2018
    Publication date: July 12, 2018
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Naoki ITABASHI
  • Publication number: 20180131330
    Abstract: An amplifier includes a printed circuit board that includes an output terminal for outputting a electrical signal to an outside and a bias terminal for receiving a bias of the electrical signal from the outside, and an integrated circuit, a capacitor, an inductor, and a ferrite bead element mounted on the printed circuit board. The integrated circuit includes a driving circuit and an output end, and outputs the electrical signal generated by the driving circuit from the output end. The capacitor is connected between the output end and the output terminal A series circuit including the inductor and the ferrite bead element connected to each other in series, the inductor is connected to the output end, and the ferrite bead element is connected to the bias terminal.
    Type: Application
    Filed: November 9, 2017
    Publication date: May 10, 2018
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Naoki ITABASHI
  • Patent number: 9825602
    Abstract: An amplifier including a pre-amplifier, an impedance converter, and a traveling wave amplifier (TWA) is disclosed. The pre-amplifier receives a differential input signal and has a pair of first output nodes that output a first differential signal by amplifying the differential input signal. Each first output node has first output impedance. The impedance converter includes a pair of first input nodes that receive the first differential signal and a pair of second output nodes that output a second differential signal. Each first input node has first input impedance greater than the first output impedance. The impedance converter converts the first differential signal into the second differential signal. Each second output node has second output impedance smaller than the first output impedance. The TWA includes a pair of transmission lines connected to the pair of the second output nodes. Each transmission line has characteristic impedance matching with the second output impedance.
    Type: Grant
    Filed: October 20, 2016
    Date of Patent: November 21, 2017
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Naoki Itabashi, Keiji Tanaka
  • Patent number: 9698023
    Abstract: A traveling-wave amplifier includes a plurality of amplifier cells, an insulating layer, an input line, and an output line. The plurality of amplifier cells is provided on a semiconductor substrate. Each of the amplifier cells receives an input signal and generates a part of an output signal from the input signal. The insulating layer is provided on the semiconductor substrate. The input line is used to externally receive an input signal and to transmit the input signal to the amplifier cells respectively. The output line is used to transmit the output signal generated by the amplifier cells and to externally output the output signal. The thickness of the input line is smaller than the thickness of the output line, and the input line and the output line are provided on the same insulating layer.
    Type: Grant
    Filed: August 31, 2015
    Date of Patent: July 4, 2017
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Naoki Itabashi, Taizo Tatsumi, Masataka Watanabe
  • Publication number: 20170117860
    Abstract: An amplifier including a pre-amplifier, an impedance converter, and a traveling wave amplifier (TWA) is disclosed. The pre-amplifier receives a differential input signal and has a pair of first output nodes that output a first differential signal by amplifying the differential input signal. Each first output node has first output impedance. The impedance converter includes a pair of first input nodes that receive the first differential signal and a pair of second output nodes that output a second differential signal. Each first input node has first input impedance greater than the first output impedance. The impedance converter converts the first differential signal into the second differential signal. Each second output node has second output impedance smaller than the first output impedance. The TWA includes a pair of transmission lines connected to the pair of the second output nodes. Each transmission line has characteristic impedance matching with the second output impedance.
    Type: Application
    Filed: October 20, 2016
    Publication date: April 27, 2017
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Naoki ITABASHI, Keiji TANAKA