Patents by Inventor Kazushi SAWADA

Kazushi SAWADA 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).

  • Switching circuit and envelope signal amplifier
    Patent number: 8878604
    Abstract: A switching circuit according to one embodiment has: N switching elements; a connection circuit including N?1 first inductance elements that are connected in series; a second inductance element; and N third inductance elements. Control terminals of the N switching elements are connected to ends of the connection circuit and connection contacts, respectively. One end of the second inductance element is connected to a power supply. The N third inductance elements electrically connects one ends of the N switching elements and the other end of the second inductance element with each other, respectively.
    Type: Grant
    Filed: March 28, 2011
    Date of Patent: November 4, 2014
    Assignees: Sumitomo Electric Industries, Ltd., National University Corporation Toyohashi University of Technology
    Inventors: Takashi Ohira, Kazuyuki Wada, Mitsutoshi Nakata, Kazushi Sawada, Satoshi Hatsukawa, Nobuo Shiga, Kazuhiro Fujikawa
  • Switching circuit
    Patent number: 8536930
    Abstract: A switching circuit according to one embodiment includes: a switching element that has a first terminal and a second terminal, and is driven by a pulse signal to switch a conduction state between the first and second terminals; a power source section that supplies a voltage to the first terminal; a load circuit that is connected in parallel with the power source section; a passive circuit section that is connected between a connection point between the power source section and the load circuit, and the first terminal, and suppresses a current flowing from the connection point to the switching element at a frequency N times (N is an integer of 1 or more) as high as a clock frequency of the pulse signal; and a resonant circuit section that is connected between the passive circuit section and the connection point, and resonates at the frequency of N times.
    Type: Grant
    Filed: June 27, 2012
    Date of Patent: September 17, 2013
    Assignees: Sumitomo Electric Industries, Ltd., National University Corporation Toyohashi University of Technology
    Inventors: Satoshi Hatsukawa, Nobuo Shiga, Kazuhiro Fujikawa, Takashi Ohira, Kazuyuki Wada, Tuya Wuren, Kazushi Sawada, Hiroshi Ishioka
  • SWITCHING CIRCUIT AND ENVELOPE SIGNAL AMPLIFIER
    Publication number: 20130049862
    Abstract: A switching circuit according to one embodiment has: N switching elements; a connection circuit including N?1 first inductance elements that are connected in series; a second inductance element; and N third inductance elements. Control terminals of the N switching elements are connected to ends of the connection circuit and connection contacts, respectively. One end of the second inductance element is connected to a power supply. The N third inductance elements electrically connects one ends of the N switching elements and the other end of the second inductance element with each other, respectively.
    Type: Application
    Filed: March 28, 2011
    Publication date: February 28, 2013
    Applicants: National University Corporation TOYOHASHI UNIVERSITY OF TECHNOLOGY, Sumitomo Electric Industries, Ltd.
    Inventors: Takashi Ohira, Kazuyuki Wada, Mitsutoshi Nakata, Kazushi Sawada, Satoshi Hatsukawa, Nobuo Shiga, Kazuhiro Fujikawa
  • SWITCHING CIRCUIT
    Publication number: 20120326774
    Abstract: A switching circuit according to one embodiment includes: a switching element that has a first terminal and a second terminal, and is driven by a pulse signal to switch a conduction state between the first and second terminals; a power source section that supplies a voltage to the first terminal; a load circuit that is connected in parallel with the power source section; a passive circuit section that is connected between a connection point between the power source section and the load circuit, and the first terminal, and suppresses a current flowing from the connection point to the switching element at a frequency N times (N is an integer of 1 or more) as high as a clock frequency of the pulse signal; and a resonant circuit section that is connected between the passive circuit section and the connection point, and resonates at the frequency of N times.
    Type: Application
    Filed: June 27, 2012
    Publication date: December 27, 2012
    Applicants: National University Corporation TOYOHASHI UNIVERSITY OF TECHNOLOGY, Sumitomo Electric Industries, Ltd.
    Inventors: Satoshi HATSUKAWA, Nobuo SHIGA, Kazuhiro FUJIKAWA, Takashi OHIRA, Kazuyuki WADA, Tuya WUREN, Kazuya ISHIOKA, Kazushi SAWADA, Hiroshi Ishioka