Patents by Inventor Tsunehiro Ohno

Tsunehiro Ohno 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).

  • Power supply device
    Patent number: 9287783
    Abstract: A PFC (Power Factor Correction) circuit improves the power factor of rectified power. Upon receiving output of the PFC circuit, a first DC-DC converter generates a voltage to be supplied to a load. Upon receiving output of the PFC circuit, a second DC-DC converter and a third DC-DC converter generate a control voltage. The second DC-DC converter and the third DC-DC converter are cascade-connected. An input terminal of the third DC-DC converter is connected to both an output terminal of the second DC-DC converter and an output terminal of the first DC-DC converter.
    Type: Grant
    Filed: December 6, 2013
    Date of Patent: March 15, 2016
    Assignee: FDK CORPORATION
    Inventors: Shigeharu Yamashita, Tsunehiro Ohno, Kazuomi Watanabe
  • POWER SUPPLY DEVICE
    Publication number: 20140092640
    Abstract: A PFC (Power Factor Correction) circuit improves the power factor of rectified power. Upon receiving output of the PFC circuit, a first DC-DC converter generates a voltage to be supplied to a load. Upon receiving output of the PFC circuit, a second DC-DC converter and a third DC-DC converter generate a control voltage. The second DC-DC converter and the third DC-DC converter are cascade-connected. An input terminal of the third DC-DC converter is connected to both an output terminal of the second DC-DC converter and an output terminal of the first DC-DC converter.
    Type: Application
    Filed: December 6, 2013
    Publication date: April 3, 2014
    Applicant: FUJITSU TELECOM NETWORKS LIMITED
    Inventors: Shigeharu YAMASHITA, Tsunehiro Ohno, Kazuomi Watanabe
  • Current balancing circuit
    Patent number: 7236381
    Abstract: There is disclosed a current balancing circuit for use in a switching power supply unit that operates in parallel with one or more other switching power supply units with current balancing terminals connected to each other. The current balancing circuit comprises a first resistor that receives a detection signal of the output current input via a diode and outputs an output current detection voltage; a second resistor connected between the current balancing terminal and a connection point between the first resistor and the diode; an operational amplifier that outputs a signal corresponding to the different between the output current detection voltages; and a switching circuit.
    Type: Grant
    Filed: January 30, 2006
    Date of Patent: June 26, 2007
    Assignee: Fujitsu Limited
    Inventors: Tsunehiro Ohno, Shigeharu Yamashita, Kazuhiko Itakura
  • Current balancing circuit
    Publication number: 20060203524
    Abstract: There is disclosed a current balancing circuit for use in a switching power supply unit that operates in parallel with one or more other switching power supply units with current balancing terminals connected to each other. The current balancing circuit comprises a first resistor that receives a detection signal of the output current input via a diode and outputs an output current detection voltage; a second resistor connected between the current balancing terminal and a connection point between the first resistor and the diode; an operational amplifier that outputs a signal corresponding to the different between the output current detection voltages; and a switching circuit.
    Type: Application
    Filed: January 30, 2006
    Publication date: September 14, 2006
    Applicant: Fujitsu Limited
    Inventors: Tsunehiro Ohno, Shigeharu Yamashita, Kazuhiko Itakura
  • Electric-power supplying devices switching between a synchronous rectification and a diode rectification by gradually altering a switching pulse
    Patent number: 6778417
    Abstract: This electric-power supplying device comprises switching elements, rectifying elements, and a control circuit. The switching elements are switched according to a switching pulse so as to perform a rectification. The rectifying elements are connected in parallel with the switching elements so as to perform a rectification. The control circuit alters the switching pulse gradually upon switching between the rectification performed by the switching elements and the rectification performed by the rectifying elements.
    Type: Grant
    Filed: March 29, 2002
    Date of Patent: August 17, 2004
    Assignees: Fujitsu Limited, Fujitsu Denso Ltd.
    Inventors: Kazuhiko Itakura, Hiroshi Shimamori, Kazutoshi Fuchigami, Tsunehiro Ohno