Patents by Inventor Ryotaro Kudo

Ryotaro Kudo 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: 7859326
    Abstract: A switching power supply device performs a stable operation with fast response for a semiconductor integrated circuit device. A capacitor is provided between the output side of an inductor and a ground potential. A first power MOSFET supplies an electric current from an input voltage to the input side of the inductor. A second power MOSFET turned on when the first power MOSFET is off allows the input side of the inductor to be of a predetermined potential. A first feedback signal corresponding to an output voltage obtained from the output side of the inductor and a second feedback signal corresponding to an electric current flowed to the first power MOSFET are used to form a PWM signal. The first power MOSFET has plural cells of a vertical type MOS-construction.
    Type: Grant
    Filed: July 10, 2008
    Date of Patent: December 28, 2010
    Assignee: Renesas Electronics Corporation
    Inventors: Toshio Nagasawa, Ryotaro Kudo
  • Publication number: 20100277143
    Abstract: To provide a power supply unit capable of realizing a multiphase power supply at low cost. For example, each of a plurality of semiconductor devices DEV[1]-DEV[n] comprises a trigger input terminal TRG_IN, a trigger output terminal TRG_OUT, and a timer circuit TM that delays a pulse signal input from TRG_IN and outputs it to TRG_OUT. DEV[1]-DEV[n] are mutually coupled in a ring shape by its own TRG_IN being coupled to TRG_OUT of one semiconductor device other than itself. Each of DEV[1]-DEV[n] performs switching operation by using the pulse signal from TRG_IN as a starting point, and feeds a current into an inductor L corresponding to itself. Moreover, DEV[1] generates the above-described pulse signal only once during startup by a start trigger terminal ST being set to a ground voltage GND, for example.
    Type: Application
    Filed: July 12, 2010
    Publication date: November 4, 2010
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Ryotaro Kudo, Toshio Nagasawa
  • Patent number: 7777462
    Abstract: To provide a power supply unit capable of realizing a multiphase power supply at low cost. For example, each of a plurality of semiconductor devices DEV[1]-DEV[n] comprises a trigger input terminal TRG_IN, a trigger output terminal TRG_OUT, and a timer circuit TM that delays a pulse signal input from TRG_IN and outputs it to TRG_OUT. DEV[1]-DEV[n] are mutually coupled in a ring shape by its own TRG_IN being coupled to TRG_OUT of one semiconductor device other than itself. Each of DEV[1]-DEV[n] performs switching operation by using the pulse signal from TRG_IN as a starting point, and feeds a current into an inductor L corresponding to itself. Moreover, DEV[1] generates the above-described pulse signal only once during startup by a start trigger terminal ST being set to a ground voltage GND, for example.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: August 17, 2010
    Assignee: Renesas Technology Corp.
    Inventors: Ryotaro Kudo, Toshio Nagasawa
  • Publication number: 20100176782
    Abstract: To provide a power supply apparatus which realizes a high-speed response, a stable operation, and a low output ripple with low power consumption. The first stage switching regulator receives an input voltage and forms a first voltage. The second stage switching regulator receives the first voltage and forms a second voltage. The second stage switching regulator includes an N-phase (N is two or more) switching regulator, and the first voltage is set to be N times a target value of the second voltage. The input voltage is set to be higher than the first voltage.
    Type: Application
    Filed: March 26, 2010
    Publication date: July 15, 2010
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventor: Ryotaro Kudo
  • Patent number: 7737672
    Abstract: To provide a power supply apparatus which realizes a high-speed response, a stable operation, and a low output ripple with low power consumption. The first stage switching regulator receives an input voltage and forms a first voltage. The second stage switching regulator receives the first voltage and forms a second voltage. The second stage switching regulator includes an N-phase (N is two or more) switching regulator, and the first voltage is set to be N times a target value of the second voltage. The input voltage is set to be higher than the first voltage.
    Type: Grant
    Filed: June 12, 2008
    Date of Patent: June 15, 2010
    Assignee: Renesas Technology Corp.
    Inventor: Ryotaro Kudo
  • Patent number: 7663354
    Abstract: The present invention provides a voltage clamping circuit which is operated in a stable manner with the simple constitution and a switching power source device which enables a high-speed operation. In a switching power source device, one of source/drain routes is connected to an input terminal to which an input voltage is supplied, a predetermined voltage to be restricted is supplied to a gate, and using a MOSFET which provides a current source between another source/drain route and a ground potential of the circuit, a clamp output voltage which corresponds to the input voltage is obtained from another source/drain route. The switching power source device further includes a first switching element which controls a current which is made to flow in an inductor such that the output voltage assumes a predetermined voltage and a second switching element which clamps an reverse electromotive voltage generated in the inductor when the first switching element is turned off to a predetermined potential.
    Type: Grant
    Filed: January 14, 2005
    Date of Patent: February 16, 2010
    Assignee: Renesas Technology Corp.
    Inventors: Ryotaro Kudo, Koji Tateno
  • Patent number: 7659144
    Abstract: Disclosed is a semiconductor device which makes it easy to design a wiring pattern for a wiring substrate on which the semiconductor device is to be mounted. In manufacturing plural semiconductor devices for providing different amounts of output current, arrangements and numbers of leads to which semiconductor chips for power transistors of the semiconductor devices are to be electrically connected are changed according to output current requirements for the semiconductor devices, whereas arrangements and numbers of leads to which semiconductor chips for control circuits of the semiconductor devices are to be electrically connected are fixed to be common to the semiconductor devices. In this way, the probability of malfunction of control circuits (PWM circuits) of the semiconductor devices can be reduced, so that a semiconductor device which makes it easy to design a wiring pattern for a wiring substrate on which the semiconductor device is to be mounted can be provided.
    Type: Grant
    Filed: December 29, 2006
    Date of Patent: February 9, 2010
    Assignee: Renesas Technology Corp.
    Inventors: Nobuyuki Shirai, Ryotaro Kudo, Yukihiro Sato
  • Publication number: 20090295351
    Abstract: The present invention provides a voltage clamping circuit which is operated in a stable manner with the simple constitution and a switching power source device which enables a high-speed operation. In a switching power source device, one of source/drain routes is connected to an input terminal to which an input voltage is supplied, a predetermined voltage to be restricted is supplied to a gate, and using a MOSFET which provides a current source between another source/drain route and a ground potential of the circuit, a clamp output voltage which corresponds to the input voltage is obtained from another source/drain route. The switching power source device further includes a first switching element which controls a current which is made to flow in an inductor such that the output voltage assumes a predetermined voltage and a second switching element which clamps an reverse electromotive voltage generated in the inductor when the first switching element is turned off to a predetermined potential.
    Type: Application
    Filed: August 3, 2009
    Publication date: December 3, 2009
    Inventors: Ryotaro Kudo, Koji Tateno
  • Publication number: 20090267587
    Abstract: In a driver circuit constructing a switching power supply device that switches power transistors passing a current through a coil by a PWM mode, a current detection transistor, which is smaller in size than the low-potential side power transistor, and a current detection resistor are provided in parallel to the low-potential side power transistor. The same control voltage as the power transistor is applied to the control terminal of the current detection transistor. An operational amplifier is formed, that has the potential of the connection node between the current detection transistor and the current detection resistor applied to its inverse input terminal and a feedback loop, so as to make a pair of input terminals of the operational amplifier be at the same potential. A signal produced by the current detection resistor is thus outputted as a current detection signal.
    Type: Application
    Filed: June 18, 2009
    Publication date: October 29, 2009
    Applicant: RENEAS TECHNOLOGY CORP.
    Inventors: Koji Tateno, Ryotaro Kudo, Shin Chiba, Kyoichi Hosokawa, Toshio Nagasawa
  • Publication number: 20090256537
    Abstract: A multiphase voltage regulator system comprises a microcontroller unit (MCU) including a reference voltage generator, and a timing generator for generating n-phase start timing signals; a load for receiving an output voltage; a comparator comparing the reference voltage and output voltage to generate a comparison result; and at least n points of load (POLs) coupled between the MCU and load for controlling output voltage in response to the n-phase start timing signals and the comparison result. Each POL may include a high-side and low-side transistor; and a D-FlipFlop, the D terminal coupled High, the clock terminal coupled to receive a control signal based on a respective one of the n-phase start timing signals, the Q terminal coupled to drive the high-side transistor, the /Q terminal coupled to drive the low-side transistor, and the reset terminal coupled to receive a reset control signal based on the comparison result.
    Type: Application
    Filed: April 11, 2008
    Publication date: October 15, 2009
    Inventors: Tetsuo Sato, Masato Ono, Ryotaro Kudo
  • Publication number: 20090224732
    Abstract: To provide a power supply unit capable of realizing a multiphase power supply at low cost. For example, each of a plurality of semiconductor devices DEV[1]-DEV[n] comprises a trigger input terminal TRG_IN, a trigger output terminal TRG_OUT, and a timer circuit TM that delays a pulse signal input from TRG_IN and outputs it to TRG_OUT. DEV[1]-DEV[n] are mutually coupled in a ring shape by its own TRG_IN being coupled to TRG_OUT of one semiconductor device other than itself. Each of DEV[1]-DEV[n] performs switching operation by using the pulse signal from TRG_IN as a starting point, and feeds a current into an inductor L corresponding to itself. Moreover, DEV[1] generates the above-described pulse signal only once during startup by a start trigger terminal ST being set to a ground voltage GND, for example.
    Type: Application
    Filed: December 15, 2008
    Publication date: September 10, 2009
    Inventors: Ryotaro Kudo, Toshio Nagasawa
  • Publication number: 20090219002
    Abstract: A capacitor is disposed between the output side and the ground potential of an inductor which creates an output voltage. A first switch element supplies a current from an input voltage to an input side of the inductor, and a second switch element which is turned on when the first switch element is off sets the input side of the inductor to a prescribed potential. A control circuit detects the arrival of the voltage on the input side of the inductor at a high voltage corresponding to the input voltage when the load circuit is in a light load state and the second switch element is off, and turns on the first switch element. It invalidates the detection output of the voltage detecting circuit when the load circuit is in a heavy load state and, after the second switch element is turned off, turns on the first switch element.
    Type: Application
    Filed: May 11, 2009
    Publication date: September 3, 2009
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Nobuyuki Shirai, Ryotaro Kudo
  • Publication number: 20090179620
    Abstract: The present invention provides a switching power source and a semiconductor integrated circuit which realize an acquisition a sufficient driving voltage of a high-potential side switching element M1 even when a power source voltage VDD is low.
    Type: Application
    Filed: March 13, 2009
    Publication date: July 16, 2009
    Inventors: KYOICHI HOSOKAWA, Ryotaro Kudo, Toshio Nagasawa, Koji Tateno
  • Patent number: 7550959
    Abstract: In a driver circuit constructing a switching power supply device that switches power transistors passing a current through a coil by a PWM mode, a current detection transistor, which is smaller in size than the low-potential side power transistor, and a current detection resistor are provided in parallel to the low-potential side power transistor. The same control voltage as the power transistor is applied to the control terminal of the current detection transistor. An operational amplifier is formed, that has the potential of the connection node between the current detection transistor and the current detection resistor applied to its inverse input terminal and a feedback loop, so as to make a pair of input terminals of the operational amplifier be at the same potential. A signal produced by the current detection resistor is thus outputted as a current detection signal.
    Type: Grant
    Filed: January 22, 2008
    Date of Patent: June 23, 2009
    Assignee: Renesas Technology Corp.
    Inventors: Koji Tateno, Ryotaro Kudo, Shin Chiba, Kyoichi Hosokawa, Toshio Nagasawa
  • Patent number: 7548050
    Abstract: A capacitor is disposed between the output side and the ground potential of an inductor which creates an output voltage. A first switch element supplies a current from an input voltage to an input side of the inductor, and a second switch element which is turned on when the first switch element is off sets the input side of the inductor to a prescribed potential. A control circuit detects the arrival of the voltage on the input side of the inductor at a high voltage corresponding to the input voltage when the load circuit is in a light load state and the second switch element is off, and turns on the first switch element. It invalidates the detection output of the voltage detecting circuit when the load circuit is in a heavy load state and, after the second switch element is turned off, turns on the first switch element.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: June 16, 2009
    Assignee: Renesas Technology Corp.
    Inventors: Nobuyuki Shirai, Ryotaro Kudo
  • Patent number: 7514908
    Abstract: The present invention provides a switching power source and a semiconductor integrated circuit which realize an acquisition a sufficient driving voltage of a high-potential side switching element M1 even when a power source voltage VDD is low.
    Type: Grant
    Filed: January 14, 2005
    Date of Patent: April 7, 2009
    Assignee: Renesas Technology Corp.
    Inventors: Kyoichi Hosokawa, Ryotaro Kudo, Toshio Nagasawa, Koji Tateno
  • Publication number: 20090039843
    Abstract: To provide a power supply apparatus which realizes a high-speed response, a stable operation, and a low output ripple with low power consumption. The first stage switching regulator receives an input voltage and forms a first voltage. The second stage switching regulator receives the first voltage and forms a second voltage. The second stage switching regulator includes an N-phase (N is two or more) switching regulator, and the first voltage is set to be N times a target value of the second voltage. The input voltage is set to be higher than the first voltage.
    Type: Application
    Filed: June 12, 2008
    Publication date: February 12, 2009
    Inventor: Ryotaro KUDO
  • Publication number: 20090015220
    Abstract: A switching power supply device performs a stable operation with fast response for a semiconductor integrated circuit device. A capacitor is provided between the output side of an inductor and a ground potential. A first power MOSFET supplies an electric current from an input voltage to the input side of the inductor. A second power MOSFET turned on when the first power MOSFET is off allows the input side of the inductor to be of a predetermined potential. A first feedback signal corresponding to an output voltage obtained from the output side of the inductor and a second feedback signal corresponding to an electric current flowed to the first power MOSFET are used to form a PWM signal. The first power MOSFET has plural cells of a vertical type MOS-construction.
    Type: Application
    Filed: July 10, 2008
    Publication date: January 15, 2009
    Inventors: Toshio Nagasawa, Ryotaro Kudo
  • Publication number: 20080224676
    Abstract: The present invention provides a voltage clamping circuit which is operated in a stable manner with the simple constitution and a switching power source device which enables a high-speed operation. In a switching power source device, one of source/drain routes is connected to an input terminal to which an input voltage is supplied, a predetermined voltage to be restricted is supplied to a gate, and using a MOSFET which provides a current source between another source/drain route and a ground potential of the circuit, a clamp output voltage which corresponds to the input voltage is obtained from another source/drain route. The switching power source device further includes a first switching element which controls a current which is made to flow in an inductor such that the output voltage assumes a predetermined voltage and a second switching element which clamps an reverse electromotive voltage generated in the inductor when the first switching element is turned off to a predetermined potential.
    Type: Application
    Filed: January 14, 2005
    Publication date: September 18, 2008
    Inventors: Ryotaro Kudo, Koji Tateno
  • Patent number: 7408388
    Abstract: There are provided a switching power supply device performing a stable operation with fast response, a semiconductor integrated circuit device, and a power supply device. A capacitor is provided between the output side of an inductor and a ground potential. A first power MOSFET supplies an electric current from an input voltage to the input side of the inductor. A second power MOSFET turned on when the first power MOSFET is off allows the input side of the inductor to be of a predetermined potential. A first feedback signal corresponding to an output voltage obtained from the output side of the inductor and a second feedback signal corresponding to an electric current flowed to the first power MOSFET are used to form a PWM signal. The first power MOSFET has plural cells of a vertical type MOS-construction. The number of cells is 1/N. A detection MOSFET in which the gains and the drains are shared over the same semiconductor substrate with the first power MOSFET is provided to form a second feedback signal.
    Type: Grant
    Filed: October 26, 2006
    Date of Patent: August 5, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Toshio Nagasawa, Ryotaro Kudo