Patents by Inventor Muga Imamura

Muga Imamura 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: 12283947
    Abstract: A switching device includes: an N-type semiconductor substrate; a power MISFET having the N-type semiconductor substrate as its drain; an input electrode receiving an input signal; a control circuit generating a gate control signal for the power MISFET according to the input signal; and a negative current prevention circuit provided between the input electrode and the control circuit. The negative current prevention circuit includes: a P-channel MISFET connected, with its drain toward the input electrode and its source and back gate toward the control circuit, between the input electrode and the control circuit, with its gate fed with a fixed potential, with the potential at its back gate separated from the potential of the N-type semiconductor substrate; and a diode connected, with its anode toward the input electrode and its cathode toward the control circuit, between the input electrode and the control circuit.
    Type: Grant
    Filed: September 15, 2023
    Date of Patent: April 22, 2025
    Assignee: Rohm Co., Ltd.
    Inventors: Katsuaki Yamada, Shuntaro Takahashi, Muga Imamura
  • Publication number: 20240007103
    Abstract: A switching device includes: an N-type semiconductor substrate; a power MISFET having the N-type semiconductor substrate as its drain; an input electrode receiving an input signal; a control circuit generating a gate control signal for the power MISFET according to the input signal; and a negative current prevention circuit provided between the input electrode and the control circuit. The negative current prevention circuit includes: a P-channel MISFET connected, with its drain toward the input electrode and its source and back gate toward the control circuit, between the input electrode and the control circuit, with its gate fed with a fixed potential, with the potential at its back gate separated from the potential of the N-type semiconductor substrate; and a diode connected, with its anode toward the input electrode and its cathode toward the control circuit, between the input electrode and the control circuit.
    Type: Application
    Filed: September 15, 2023
    Publication date: January 4, 2024
    Inventors: Katsuaki YAMADA, Shuntaro TAKAHASHI, Muga IMAMURA
  • Patent number: 9862239
    Abstract: An antenna driving device includes an antenna driving circuit arranged to generate driving current of a transmission antenna, a power supply circuit arranged to generate an output voltage from an input voltage so as to supply the output voltage to the antenna driving circuit, and a logic circuit arranged to control the antenna driving circuit and the power supply circuit. The power supply circuit has a function of temporarily disabling current feedback control so as to perform voltage feedback control using a reference value just before halting the drive of the transmission antenna when the power supply circuit restarts to drive the transmission antenna, or has a function of performing variable control of a reference value for current feedback control in accordance with a rising edge of the driving current when the power supply circuit restarts to drive the transmission antenna.
    Type: Grant
    Filed: October 20, 2016
    Date of Patent: January 9, 2018
    Assignee: Rohm Co., Ltd.
    Inventors: Naoki Takahashi, Masaki Omi, Muga Imamura, Yohei Okuno
  • Publication number: 20170036498
    Abstract: An antenna driving device includes an antenna driving circuit arranged to generate driving current of a transmission antenna, a power supply circuit arranged to generate an output voltage from an input voltage so as to supply the output voltage to the antenna driving circuit, and a logic circuit arranged to control the antenna driving circuit and the power supply circuit. The power supply circuit has a function of temporarily disabling current feedback control so as to perform voltage feedback control using a reference value just before halting the drive of the transmission antenna when the power supply circuit restarts to drive the transmission antenna, or has a function of performing variable control of a reference value for current feedback control in accordance with a rising edge of the driving current when the power supply circuit restarts to drive the transmission antenna.
    Type: Application
    Filed: October 20, 2016
    Publication date: February 9, 2017
    Inventors: Naoki Takahashi, Masaki Omi, Muga Imamura, Yohei Okuno
  • Patent number: 9502756
    Abstract: An antenna driving device includes an antenna driving circuit arranged to generate driving current of a transmission antenna, a power supply circuit arranged to generate an output voltage from an input voltage so as to supply the output voltage to the antenna driving circuit, and a logic circuit arranged to control the antenna driving circuit and the power supply circuit. The power supply circuit has a function of temporarily disabling current feedback control so as to perform voltage feedback control using a reference value just before halting the drive of the transmission antenna when the power supply circuit restarts to drive the transmission antenna, or has a function of performing variable control of a reference value for current feedback control in accordance with a rising edge of the driving current when the power supply circuit restarts to drive the transmission antenna.
    Type: Grant
    Filed: September 17, 2014
    Date of Patent: November 22, 2016
    Assignee: Rohm Co., Ltd.
    Inventors: Naoki Takahashi, Masaki Omi, Muga Imamura, Yohei Okuno
  • Patent number: 9391603
    Abstract: A semiconductor device has a first chip and a second chip sealed in a single package. The first chip includes a regulator which generates an internal voltage from a supply voltage, a reset circuit which monitors the supply voltage and the internal voltage to generate a reset signal, and a controlled circuit which operates by being supplied with the supply voltage. The second chip includes a controlling circuit which generates a control signal for the controlled circuit by being supplied with the internal voltage. The reset signal is fed to both the controlling circuit and the controlled circuit.
    Type: Grant
    Filed: October 24, 2013
    Date of Patent: July 12, 2016
    Assignee: Rohm Co., Ltd.
    Inventors: Takashi Fujimura, Muga Imamura, Hirofumi Yuki
  • Publication number: 20150079914
    Abstract: An antenna driving device includes an antenna driving circuit arranged to generate driving current of a transmission antenna, a power supply circuit arranged to generate an output voltage from an input voltage so as to supply the output voltage to the antenna driving circuit, and a logic circuit arranged to control the antenna driving circuit and the power supply circuit. The power supply circuit has a function of temporarily disabling current feedback control so as to perform voltage feedback control using a reference value just before halting the drive of the transmission antenna when the power supply circuit restarts to drive the transmission antenna, or has a function of performing variable control of a reference value for current feedback control in accordance with a rising edge of the driving current when the power supply circuit restarts to drive the transmission antenna.
    Type: Application
    Filed: September 17, 2014
    Publication date: March 19, 2015
    Inventors: Naoki Takahashi, Masaki Omi, Muga Imamura, Yohei Okuno
  • Publication number: 20140117891
    Abstract: A semiconductor device has a first chip and a second chip sealed in a single package. The first chip includes a regulator which generates an internal voltage from a supply voltage, a reset circuit which monitors the supply voltage and the internal voltage to generate a reset signal, and a controlled circuit which operates by being supplied with the supply voltage. The second chip includes a controlling circuit which generates a control signal for the controlled circuit by being supplied with the internal voltage. The reset signal is fed to both the controlling circuit and the controlled circuit.
    Type: Application
    Filed: October 24, 2013
    Publication date: May 1, 2014
    Applicant: Rohm Co., Ltd.
    Inventors: Takashi FUJIMURA, Muga IMAMURA, Hirofumi YUKI
  • Publication number: 20070265998
    Abstract: An information processing device retrieves external data stored in an external memory and performs predetermined first processing for the external data thus retrieved. Here, the information processing device has: a storage that stores retrieval control information transmitted from outside; and a retrieval controller that controls retrieval of the external data according to the retrieval control information. This makes it possible to efficiently perform the retrieval of data from the external memory, and alleviate the burden on a control device corresponding to a BB-CPU.
    Type: Application
    Filed: May 10, 2007
    Publication date: November 15, 2007
    Applicant: ROHM CO., LTD.
    Inventors: Tatsuya Mori, Takashi Esumi, Muga Imamura