Patents by Inventor Yoichi Tokai

Yoichi Tokai 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: 20210298148
    Abstract: A DC-DC power supply according to an embodiment includes a voltage converter, a first switching element, a second switching element, and a controller. The voltage converter converts an input voltage into a first voltage. The first switching element performs switching according to a pulse signal to thereby intermit the first voltage applied to one end of a load. One end of the second switching element is connected to the other end of the load. The second switching element performs an ON/OFF operation at a predetermined advance time with respect to the first switching element. The controller controls, based on a voltage at the other end of the second switching element in a one-voltage holder, the first voltage output by the voltage converter.
    Type: Application
    Filed: September 4, 2020
    Publication date: September 23, 2021
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Yoichi TOKAI, Toru TAKAYAMA
  • Patent number: 10903832
    Abstract: A current drive circuit has a first transistor that outputs a current, a second transistor connected to the first transistor by cascode connection, a third transistor connected to the second transistor by cascode connection, a first current source that supplies a current to the third transistor and the second transistor, a fourth transistor that shares a gate with the third transistor, a fifth transistor that is connected to the fourth transistor by cascode connection and shares a gate with the second transistor, a second current source that supplies a current to the fourth transistor and the fifth transistor, a sixth transistor that shares a gate with the third transistor and the fourth transistor and controls a gate voltage of the first transistor, and a third current source that supplies a drain current of the sixth transistor.
    Type: Grant
    Filed: March 11, 2019
    Date of Patent: January 26, 2021
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventor: Yoichi Tokai
  • Publication number: 20190296733
    Abstract: A current drive circuit has a first transistor that outputs a current, a second transistor connected to the first transistor by cascode connection, a third transistor connected to the second transistor by cascode connection, a first current source that supplies a current to the third transistor and the second transistor, a fourth transistor that shares a gate with the third transistor, a fifth transistor that is connected to the fourth transistor by cascode connection and shares a gate with the second transistor, a second current source that supplies a current to the fourth transistor and the fifth transistor, a sixth transistor that shares a gate with the third transistor and the fourth transistor and controls a gate voltage of the first transistor, and a third current source that supplies a drain current of the sixth transistor.
    Type: Application
    Filed: March 11, 2019
    Publication date: September 26, 2019
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventor: Yoichi TOKAI
  • Patent number: 10128849
    Abstract: According to one embodiment, a level shift circuit includes a first transistor, a second transistor, third transistor, fourth transistor, fifth transistor, sixth transistor, seventh transistor and eighth transistor. The level shift circuit also includes a first capacitance element, a second capacitance element, third capacitance element and fourth capacitance element. The first through eighth transistors have a first conductivity type. The first through fourth transistors are included to a bi-stable multi-vibrator. The fifth through the eighth transistors are included to an active load for the differential input of the signal through the third capacitance element and the fourth capacitance element.
    Type: Grant
    Filed: August 4, 2016
    Date of Patent: November 13, 2018
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoichi Tokai
  • Patent number: 9680466
    Abstract: The analog switch includes a first DMOS transistor of a second conductivity type that is connected to an input terminal at a first end of a current path thereof and to the gate of the first MOS transistor at a second end of the current path, and is controlled in accordance with the second current. The analog switch includes a second DMOS transistor of the second conductivity type that is connected to the second end of the current path of the first DMOS transistor at a first end of a current path thereof and to an output terminal at a second end of the current path and is controlled in accordance with the second current. The analog switch includes a first switch element that is connected between a gate and the second end of the current path of the first DMOS transistor.
    Type: Grant
    Filed: September 8, 2015
    Date of Patent: June 13, 2017
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoichi Tokai
  • Publication number: 20170104489
    Abstract: According to one embodiment, a level shift circuit includes a first transistor, a second transistor, third transistor, fourth transistor, fifth transistor, sixth transistor, seventh transistor and eighth transistor. The level shift circuit also includes a first capacitance element, a second capacitance element, third capacitance element and fourth capacitance element. The first through eighth transistors have a first conductivity type. The first through fourth transistors are included to a bi-stable multi-vibrator. The fifth through the eighth transistors are included to an active load for the differential input of the signal through the third capacitance element and the fourth capacitance element.
    Type: Application
    Filed: August 4, 2016
    Publication date: April 13, 2017
    Inventor: Yoichi Tokai
  • Publication number: 20160204780
    Abstract: The analog switch includes a first DMOS transistor of a second conductivity type that is connected to an input terminal at a first end of a current path thereof and to the gate of the first MOS transistor at a second end of the current path, and is controlled in accordance with the second current. The analog switch includes a second DMOS transistor of the second conductivity type that is connected to the second end of the current path of the first DMOS transistor at a first end of a current path thereof and to an output terminal at a second end of the current path and is controlled in accordance with the second current. The analog switch includes a first switch element that is connected between a gate and the second end of the current path of the first DMOS transistor.
    Type: Application
    Filed: September 8, 2015
    Publication date: July 14, 2016
    Inventor: Yoichi Tokai
  • Patent number: 9178428
    Abstract: The step-down switching circuit includes an amplifier capacitor having a first end connected to the feedback terminal and a second end connected to a second input of the amplifier. The step-down switching circuit includes a first resistor having a first end connected to the first end of the amplifier capacitor. The step-down switching circuit includes a second resistor having a first end connected to a second end of the first resistor and a second end connected to an output of the amplifier. The step-down switching circuit includes a third resistor having a first end connected to the second end of the first resistor and a second end connected to the second end of the amplifier capacitor.
    Type: Grant
    Filed: August 29, 2013
    Date of Patent: November 3, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoichi Tokai
  • Patent number: 8963522
    Abstract: According to one embodiment, a circuit includes an amplifier, first and second capacitors, a switch and a monitoring-comparator. The amplifier amplifies source and drain voltages to output first and second amplified-signals. The first and second capacitors are connected to the amplifier's first and second terminals. The first and second amplified-signals are outputted from the first and second terminals. The switch forms first and second loops when a switching-transistor is OFF. The switch supplies a common-reference-voltage to the first and second loops to store charge in the first and second capacitors. The switch ends the first and second loops based on a gate-signal when the switching-transistor is ON. The monitoring-comparator compares first and second inputs. The monitoring-comparator outputs a signal depending on a comparison result when the switching-transistor is ON. The first and second inputs are input through the first and second capacitors.
    Type: Grant
    Filed: January 23, 2012
    Date of Patent: February 24, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masafumi Otsuka, Yoichi Tokai
  • Publication number: 20140266095
    Abstract: The step-down switching circuit includes an amplifier capacitor having a first end connected to the feedback terminal and a second end connected to a second input of the amplifier. The step-down switching circuit includes a first resistor having a first end connected to the first end of the amplifier capacitor. The step-down switching circuit includes a second resistor having a first end connected to a second end of the first resistor and a second end connected to an output of the amplifier. The step-down switching circuit includes a third resistor having a first end connected to the second end of the first resistor and a second end connected to the second end of the amplifier capacitor.
    Type: Application
    Filed: August 29, 2013
    Publication date: September 18, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yoichi Tokai
  • Patent number: 8797007
    Abstract: A DC-DC converter includes a smoothing capacitor connected between a first output terminal connected to a first end of a load and a second output terminal connected to a second end of the load, the smoothing capacitor smoothing an output voltage. The DC-DC converter includes a choke coil having a first end connected to a first end of a battery. The DC-DC converter includes a semiconductor integrated circuit having a switch terminal connected to a second end of the choke coil, a first potential terminal connected to the first output terminal, and a second potential terminal connected to the second output terminal and a second end of the battery.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: August 5, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoichi Tokai
  • Publication number: 20130141060
    Abstract: A DC-DC converter includes a smoothing capacitor connected between a first output terminal connected to a first end of a load and a second output terminal connected to a second end of the load, the smoothing capacitor smoothing an output voltage. The DC-DC converter includes a choke coil having a first end connected to a first end of a battery. The DC-DC converter includes a semiconductor integrated circuit having a switch terminal connected to a second end of the choke coil, a first potential terminal connected to the first output terminal, and a second potential terminal connected to the second output terminal and a second end of the battery.
    Type: Application
    Filed: March 14, 2012
    Publication date: June 6, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventor: Yoichi TOKAI
  • Publication number: 20120235656
    Abstract: According to one embodiment, a circuit includes an amplifier, first and second capacitors, a switch and a monitoring-comparator. The amplifier amplifies source and drain voltages to output first and second amplified-signals. The first and second capacitors are connected to the amplifier's first and second terminals. The first and second amplified-signals are outputted from the first and second terminals. The switch forms first and second loops when a switching-transistor is OFF. The switch supplies a common-reference-voltage to the first and second loops to store charge in the first and second capacitors. The switch ends the first and second loops based on a gate-signal when the switching-transistor is ON. The monitoring-comparator compares first and second inputs. The monitoring-comparator outputs a signal depending on a comparison result when the switching-transistor is ON. The first and second inputs are input through the first and second capacitors.
    Type: Application
    Filed: January 23, 2012
    Publication date: September 20, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masafumi OTSUKA, Yoichi Tokai
  • Patent number: 8207722
    Abstract: A boost DC/DC converter has a voltage dividing circuit connected between the output terminal and the ground, that outputs a divided voltage obtained by dividing the output voltage; a reference voltage generating circuit that generates a reference voltage based on the input voltage; an error amplifier that outputs a first signal corresponding to the difference between the divided voltage and the reference voltage; a feedforward circuit that detects the input voltage and outputs a second signal corresponding to a current inversely proportional to the input voltage; a multiplier that multiples the first signal by the second signal and outputs a third signal obtained; and a control circuit that outputs, based on the third signal, a control signal for controlling on/off of the switching transistor so that the divided voltage is equal to the reference voltage.
    Type: Grant
    Filed: August 25, 2009
    Date of Patent: June 26, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masafumi Otsuka, Yoichi Tokai, Ryo Tanifuji
  • Publication number: 20110221415
    Abstract: According to one embodiment, a switching transistor changes, based on ON/OFF operations, the direction of an electric current flowing to an inductor. A gate driving unit applies a driving voltage to a gate of the switching transistor. A power-supply switching unit switches, based on a result of comparison of the input voltage and the output voltage, the voltage of a power supply that generates the driving voltage.
    Type: Application
    Filed: March 7, 2011
    Publication date: September 15, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masafumi Otsuka, Yoichi Tokai, Ryo Tanifuji
  • Publication number: 20100052627
    Abstract: A boost DC/DC converter has a voltage dividing circuit connected between the output terminal and the ground, that outputs a divided voltage obtained by dividing the output voltage; a reference voltage generating circuit that generates a reference voltage based on the input voltage; an error amplifier that outputs a first signal corresponding to the difference between the divided voltage and the reference voltage; a feedforward circuit that detects the input voltage and outputs a second signal corresponding to a current inversely proportional to the input voltage; a multiplier that multiples the first signal by the second signal and outputs a third signal obtained; and a control circuit that outputs, based on the third signal, a control signal for controlling on/off of the switching transistor so that the divided voltage is equal to the reference voltage.
    Type: Application
    Filed: August 25, 2009
    Publication date: March 4, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masafumi Otsuka, Yoichi Tokai, Ryo Tanifuji
  • Patent number: 6696858
    Abstract: A semiconductor integrated circuit device includes a level-shifting circuit, a current mirror circuit and a switch circuit. The level-shifting circuit level-shifts an input signal having a first amplitude to an output signal having a second amplitude. The current mirror circuit charges or discharges an output node of the level-shifting circuit. The switch circuit operates the current mirror circuit during a period from the inversion of the input signal to the inversion of the output signal.
    Type: Grant
    Filed: September 5, 2001
    Date of Patent: February 24, 2004
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoichi Tokai
  • Publication number: 20020044171
    Abstract: An ink-jet recording apparatus according to the present invention, which records an image onto a recording medium by flying an ink-droplet from a surface of an ink by a pressure of ultrasonic beam, is characterized by comprising ultrasonic generating element array which has a plurality of ultrasonic elements arranged in array for emitting ultrasonic beams, driving means for applying a plurality of pulses having different phases each other to converging ultrasonic beams by interfering said plurality of ultrasonic beams with each other emitted from said ultrasonic generating elements of a part of said ultrasonic generating element array, which are simultaneously driven, with sequentially shifting said ultrasonic generating elements simultaneously driven to an array direction, and converging means for converging each of said plurality of ultrasonic beams in a direction of perpendicular to the array direction.
    Type: Application
    Filed: October 12, 1999
    Publication date: April 18, 2002
    Inventors: SHUZO HIRAHARA, TUTOMU SAITO, HITOSHI NAGATO, TETSURO ITAKURA, SATOSHI TAKAYAMA, HIDEKI NUKADA, SHUNSUKE HATTORI, NORIKO Y. KUDO, SHIROH SAITOH, MASAMI SUGIUCHI, YOICHI TOKAI, FIMIHIKO MURAKAMI, HISAKO TANAKA, CHIAKI TANUMA, MAMORU IZUMI, ISAO AMEMIYA, ATSUKO NAKAMURA, SEIZABUROU SHIMIZU, KUMI OKUWADA
  • Publication number: 20020027450
    Abstract: A semiconductor integrated circuit device includes a level-shifting circuit, a current mirror circuit and a switch circuit. The level-shifting circuit level-shifts an input signal having a first amplitude to an output signal having a second amplitude. The current mirror circuit charges or discharges an output node of the level-shifting circuit. The switch circuit operates the current mirror circuit during a period from the inversion of the input signal to the inversion of the output signal.
    Type: Application
    Filed: September 5, 2001
    Publication date: March 7, 2002
    Inventor: Yoichi Tokai
  • Patent number: 6336978
    Abstract: A heat regenerative material including AMz, where A is at least one rare earth element selected from the group consisting of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb; M is at least one metal selected from the group consisting of Ni and Co; and z is 0.001 to 9.0; the heat regenerative material being formed of particles with an average diameter of 1-2,000 &mgr;m or filaments with an average diameter of 1-2,000 &mgr;m.
    Type: Grant
    Filed: October 18, 1999
    Date of Patent: January 8, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoichi Tokai, Masashi Sahashi