Patents by Inventor Yuko KITAJI

Yuko KITAJI 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: 10911042
    Abstract: There is a need to provide a semiconductor device, a semiconductor system, and a semiconductor device manufacturing method capable of accurately monitoring a minimum operating voltage for a monitoring-targeted circuit. A monitor portion of a semiconductor system according to one embodiment includes a voltage monitor and a delay monitor. The voltage monitor is driven by power-supply voltage SVCC different from power-supply voltage VDD supplied to an internal circuit as a monitoring-targeted circuit and monitors power-supply voltage VDD. The delay monitor is driven by power-supply voltage VDD and monitors signal propagation time for a critical path in the internal circuit. The delay monitor is configured so that a largest on-resistance of on-resistances for a plurality of transistors configuring the delay monitor is smaller than a largest on-resistance of on-resistances for a plurality of transistors configuring the internal circuit.
    Type: Grant
    Filed: July 25, 2018
    Date of Patent: February 2, 2021
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Kazuki Fukuoka, Toshifumi Uemura, Yuko Kitaji
  • Patent number: 10884035
    Abstract: A semiconductor device, a semiconductor system, and a control method of a semiconductor device are capable of accurately monitoring the lowest operating voltage of a circuit to be monitored. According to one embodiment, a monitor unit of a semiconductor system includes a voltage monitor that is driven by a second power supply voltage different from a first power supply voltage supplied to an internal circuit that is a circuit to be monitored and monitors the first power supply voltage, and a delay monitor that is driven by the first power supply voltage and monitors the signal propagation period of time of a critical path in the internal circuit.
    Type: Grant
    Filed: October 8, 2019
    Date of Patent: January 5, 2021
    Assignee: Renesas Electronics Corporation
    Inventors: Kazuki Fukuoka, Toshifumi Uemura, Yuko Kitaji, Yosuke Okazaki, Akira Murayama
  • Patent number: 10782763
    Abstract: A semiconductor device includes a voltage sensor which samples a power supply voltage at a speed faster than fluctuations in the power supply voltage and encodes the power supply voltage into a voltage code value. A voltage drop determination circuit detects a voltage drop based on the voltage code value, and a clock control circuit generates a clock. The clock control circuit stops the clock when the voltage drop determination circuit detects the voltage drop. The voltage drop determination circuit includes a prediction computation circuit which looks ahead a voltage value from a history of the voltage code value and predicts a variation value, and the prediction computation circuit includes a circuit for masking a prediction value if a differential value of the prediction value is continuously negative for a predetermined cycle.
    Type: Grant
    Filed: December 13, 2018
    Date of Patent: September 22, 2020
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Yuko Kitaji, Kazuki Fukuoka, Ryo Mori, Toshifumi Uemura
  • Publication number: 20200041547
    Abstract: A semiconductor device, a semiconductor system, and a control method of a semiconductor device are capable of accurately monitoring the lowest operating voltage of a circuit to be monitored. According to one embodiment, a monitor unit of a semiconductor system includes a voltage monitor that is driven by a second power supply voltage different from a first power supply voltage supplied to an internal circuit that is a circuit to be monitored and monitors the first power supply voltage, and a delay monitor that is driven by the first power supply voltage and monitors the signal propagation period of time of a critical path in the internal circuit.
    Type: Application
    Filed: October 8, 2019
    Publication date: February 6, 2020
    Inventors: Kazuki FUKUOKA, Toshifumi UEMURA, Yuko KITAJI, Yosuke OKAZAKI, Akira MURAYAMA
  • Patent number: 10481185
    Abstract: A semiconductor device, a semiconductor system, and a control method of a semiconductor device are capable of accurately monitoring the lowest operating voltage of a circuit to be monitored. According to one embodiment, a monitor unit of a semiconductor system includes a voltage monitor that is driven by a second power supply voltage different from a first power supply voltage supplied to an internal circuit that is a circuit to be monitored and monitors the first power supply voltage, and a delay monitor that is driven by the first power supply voltage and monitors the signal propagation period of time of a critical path in the internal circuit.
    Type: Grant
    Filed: September 14, 2017
    Date of Patent: November 19, 2019
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Kazuki Fukuoka, Toshifumi Uemura, Yuko Kitaji, Yosuke Okazaki, Akira Murayama
  • Publication number: 20190129488
    Abstract: A semiconductor device includes a voltage sensor which samples a power supply voltage at a speed faster than fluctuations in the power supply voltage and encodes the power supply voltage into a voltage code value. A voltage drop determination circuit detects a voltage drop based on the voltage code value, and a clock control circuit generates a clock. The clock control circuit stops the clock when the voltage drop determination circuit detects the voltage drop. The voltage drop determination circuit includes a prediction computation circuit which looks ahead a voltage value from a history of the voltage code value and predicts a variation value, and the prediction computation circuit includes a circuit for masking a prediction value if a differential value of the prediction value is continuously negative for a predetermined cycle.
    Type: Application
    Filed: December 13, 2018
    Publication date: May 2, 2019
    Inventors: Yuko Kitaji, Kazuki Fukuoka, Ryo Mori, Toshifumi Uemura
  • Publication number: 20190074829
    Abstract: There is a need to provide a semiconductor device, a semiconductor system, and a semiconductor device manufacturing method capable of accurately monitoring a minimum operating voltage for a monitoring-targeted circuit. A monitor portion of a semiconductor system according to one embodiment includes a voltage monitor and a delay monitor. The voltage monitor is driven by power-supply voltage SVCC different from power-supply voltage VDD supplied to an internal circuit as a monitoring-targeted circuit and monitors power-supply voltage VDD. The delay monitor is driven by power-supply voltage VDD and monitors signal propagation time for a critical path in the internal circuit. The delay monitor is configured so that a largest on-resistance of on-resistances for a plurality of transistors configuring the delay monitor is smaller than a largest on-resistance of on-resistances for a plurality of transistors configuring the internal circuit.
    Type: Application
    Filed: July 25, 2018
    Publication date: March 7, 2019
    Inventors: Kazuki FUKUOKA, Toshifumi UEMURA, Yuko KITAJI
  • Patent number: 10222847
    Abstract: There is provided a semiconductor device that can follow a fast voltage change such as a large voltage drop occurring at the time of rapid load fluctuation. The semiconductor device includes a voltage sensor which monitors a power supply voltage at a sampling speed higher than the assumed frequency of power supply voltage fluctuation and outputs a voltage code value, a voltage drop determination circuit which determines, from the voltage code value, that a voltage drop causing a malfunction of a system occurs, and outputs a clock stop signal, and a clock control circuit which controls clock stop, restart, and frequency change.
    Type: Grant
    Filed: July 29, 2016
    Date of Patent: March 5, 2019
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Yuko Kitaji, Kazuki Fukuoka, Ryo Mori, Toshifumi Uemura
  • Patent number: 10180711
    Abstract: There is provided a semiconductor device that can follow a fast voltage change such as a large voltage drop occurring at the time of rapid load fluctuation. The semiconductor device includes a voltage sensor which monitors a power supply voltage at a sampling speed higher than the assumed frequency of power supply voltage fluctuation and outputs a voltage code value, a voltage drop determination circuit which determines, from the voltage code value, that a voltage drop causing a malfunction of a system occurs, and outputs a clock stop signal, and a clock control circuit which controls clock stop, restart, and frequency change.
    Type: Grant
    Filed: July 29, 2016
    Date of Patent: January 15, 2019
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Yuko Kitaji, Kazuki Fukuoka, Ryo Mori, Toshifumi Uemura
  • Publication number: 20180095115
    Abstract: An object of the present invention is to provide a semiconductor device, a semiconductor system, and a control method of a semiconductor device capable of accurately monitoring the lowest operating voltage of a circuit to be monitored. According to one embodiment, a monitor unit of a semiconductor system includes a voltage monitor that is driven by a second power supply voltage different from a first power supply voltage supplied to an internal circuit that is a circuit to be monitored and monitors the first power supply voltage, and a delay monitor that is driven by the first power supply voltage and monitors the signal propagation period of time of a critical path in the internal circuit.
    Type: Application
    Filed: September 14, 2017
    Publication date: April 5, 2018
    Inventors: Kazuki FUKUOKA, Toshifumi UEMURA, Yuko KITAJI, Yosuke OKAZAKI, Akira MURAYAMA
  • Publication number: 20170075404
    Abstract: There is provided a semiconductor device that can follow a fast voltage change such as a large voltage drop occurring at the time of rapid load fluctuation. The semiconductor device includes a voltage sensor which monitors a power supply voltage at a sampling speed higher than the assumed frequency of power supply voltage fluctuation and outputs a voltage code value, a voltage drop determination circuit which determines, from the voltage code value, that a voltage drop causing a malfunction of a system occurs, and outputs a clock stop signal, and a clock control circuit which controls clock stop, restart, and frequency change.
    Type: Application
    Filed: July 29, 2016
    Publication date: March 16, 2017
    Inventors: Yuko KITAJI, Kazuki FUKUOKA, Ryo MORI, Toshifumi UEMURA