Patents by Inventor Hajime SHIJI

Hajime SHIJI 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).

  • Publication number: 20240048051
    Abstract: A method of digitally controlling a DC-DC converter includes detecting an output of the DC-DC converter; comparing the output to a target value to determine an error value; calculating a control parameter based on the error value in which an output control target is a linear function of the control parameter; converting the control parameter to a converter control parameter; and based on the converter control parameter, generating a pulse signal to control a power switch of the DC-DC converter.
    Type: Application
    Filed: August 4, 2023
    Publication date: February 8, 2024
    Applicant: Murata Manufacturing Co., Ltd.
    Inventor: Hajime SHIJI
  • Patent number: 10630180
    Abstract: An abnormality determiner turns OFF a third switch and controls a converter controller to stop operating in a case where a voltage value detected by a voltage detector during a normal mode exceeds a first threshold value. The abnormality determiner determines that a first switch has an abnormality in a case where the voltage value exceeds a second threshold value in a state where the converter controller is stopped. The abnormality determiner controls the converter controller to operate in a case where the voltage value is equal to or smaller than the second threshold value in a state where the converter controller is stopped. The abnormality determiner determines that the converter controller has an abnormality in a case where the voltage value exceeds a third threshold value in a state where the converter controller is operated.
    Type: Grant
    Filed: September 12, 2019
    Date of Patent: April 21, 2020
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Hajime Shiji, Yoshiyuki Uno, Yoshiaki Mizushima, Shouhei Hirose
  • Publication number: 20200007034
    Abstract: An abnormality determiner turns OFF a third switch and controls a converter controller to stop operating in a case where a voltage value detected by a voltage detector during a normal mode exceeds a first threshold value. The abnormality determiner determines that a first switch has an abnormality in a case where the voltage value exceeds a second threshold value in a state where the converter controller is stopped. The abnormality determiner controls the converter controller to operate in a case where the voltage value is equal to or smaller than the second threshold value in a state where the converter controller is stopped. The abnormality determiner determines that the converter controller has an abnormality in a case where the voltage value exceeds a third threshold value in a state where the converter controller is operated.
    Type: Application
    Filed: September 12, 2019
    Publication date: January 2, 2020
    Inventors: Hajime SHIJI, Yoshiyuki UNO, Yoshiaki MIZUSHIMA, Shouhei HIROSE
  • Patent number: 10128665
    Abstract: A power supply apparatus includes a converter, an output voltage detector, an output voltage controller that performs control to make a detected value of an output voltage of the power supply apparatus approach a target value in accordance with a comparison result between an output voltage of the converter and a reference voltage, and an instructed value reader that reads an instructed value regarding the output voltage from outside. A pre-bias voltage is applied across output terminals from an external circuit connected to the output terminals also during a time when the converter stops an operation. At a time when the converter starts to operate, the output voltage is set such that the output voltage becomes identical or approximately identical to a pre-bias voltage. After the output voltage has become identical or approximately identical to the pre-bias voltage, the output voltage is set such that the output voltage becomes an instructed voltage instructed from outside.
    Type: Grant
    Filed: August 12, 2016
    Date of Patent: November 13, 2018
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Masanori Konishi, Hajime Shiji, Shouhei Hirose
  • Patent number: 10128748
    Abstract: In a switching power-supply apparatus that controls magnitudes of output voltages of respective converters connected in parallel to be equal to a target voltage value, only a selected one of the converters is made to operate. In this state, correction values generated by the respective converters are received and stored in memory. Droop characteristics generated for the respective converters are corrected using the correction values. Accordingly, a switching power-supply apparatus and a droop characteristic correction method capable of correcting variations in droop characteristics generated for respective power converters are provided.
    Type: Grant
    Filed: April 27, 2018
    Date of Patent: November 13, 2018
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yoshiyuki Uno, Hajime Shiji
  • Publication number: 20180248478
    Abstract: In a switching power-supply apparatus that controls magnitudes of output voltages of respective converters connected in parallel to be equal to a target voltage value, only a selected one of the converters is made to operate. In this state, correction values generated by the respective converters are received and stored in memory. Droop characteristics generated for the respective converters are corrected using the correction values. Accordingly, a switching power-supply apparatus and a droop characteristic correction method capable of correcting variations in droop characteristics generated for respective power converters are provided.
    Type: Application
    Filed: April 27, 2018
    Publication date: August 30, 2018
    Inventors: Yoshiyuki UNO, Hajime SHIJI
  • Publication number: 20160352123
    Abstract: A power supply apparatus includes a converter, an output voltage detector, an output voltage controller that performs control to make a detected value of an output voltage of the power supply apparatus approach a target value in accordance with a comparison result between an output voltage of the converter and a reference voltage, and an instructed value reader that reads an instructed value regarding the output voltage from outside. A pre-bias voltage is applied across output terminals from an external circuit connected to the output terminals also during a time when the converter stops an operation. At a time when the converter starts to operate, the output voltage is set such that the output voltage becomes identical or approximately identical to a pre-bias voltage. After the output voltage has become identical or approximately identical to the pre-bias voltage, the output voltage is set such that the output voltage becomes an instructed voltage instructed from outside.
    Type: Application
    Filed: August 12, 2016
    Publication date: December 1, 2016
    Inventors: Masanori KONISHI, Hajime SHIJI, Shouhei HIROSE
  • Patent number: 9484841
    Abstract: A switching power supply device equipped with an inverter device includes a transformer including a primary winding and a secondary winding, which are magnetically coupled with each other. On the primary side, a capacitor and a switching element are connected in series with the primary winding and a switching element is connected in series the switching element and is connected in parallel with the primary winding and the capacitor. On the secondary side, a bidirectional switching element, which includes FETs, is connected in series with the secondary winding. A control circuit alternately turns the first switching element and the second switching element on, and turns the bidirectional switching element on in an off period of the first switching element or the second switching element. Thus, the inverter device outputs an alternating current output voltage by using a single secondary winding of a transformer.
    Type: Grant
    Filed: April 16, 2014
    Date of Patent: November 1, 2016
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventor: Hajime Shiji
  • Patent number: 9209697
    Abstract: A resonant converter circuit generates an output voltage from an input voltage by switching first and second FETs. A subsequent-stage switching control circuit alternately subjects the first and second FETs in the resonant converter circuit to on/off control with a fixed on-duty ratio and a fixed switching frequency. A boost converter circuit includes an inductor, a smoothing capacitor, and a third FET arranged to switch the energization of the inductor. A previous-stage switching control circuit subjects the third FET in the boost converter circuit to on/off control with a controlled on-duty ratio, and adjusts an output voltage to the resonant converter circuit.
    Type: Grant
    Filed: June 5, 2013
    Date of Patent: December 8, 2015
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yoshiyuki Uno, Hajime Shiji
  • Patent number: 8988901
    Abstract: A switching power supply includes a series resonant circuit that includes a resonant inductor and a resonant capacitor connected in series with a primary winding of a converter transformer. By controlling turning on and off of first and second switching elements in a complementary manner, current is supplied to the series resonant circuit. A third switching element connected on the secondary side of the converter transformer is synchronized with the first switching element, and a fourth switching element is synchronized with the second switching element. If a switching frequency is less than a resonant frequency, turning on of the third and fourth switching elements is synchronized with turning on of the first and second switching elements, and turning off of the third and fourth switching elements is controlled, without being synchronized with turning off of the first and second switching elements, after half a resonant period has elapsed.
    Type: Grant
    Filed: October 10, 2013
    Date of Patent: March 24, 2015
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takashi Hara, Hajime Shiji
  • Publication number: 20140226385
    Abstract: A switching power supply device equipped with an inverter device includes a transformer including a primary winding and a secondary winding, which are magnetically coupled with each other. On the primary side, a capacitor and a switching element are connected in series with the primary winding and a switching element is connected in series the switching element and is connected in parallel with the primary winding and the capacitor. On the secondary side, a bidirectional switching element, which includes FETs, is connected in series with the secondary winding. A control circuit alternately turns the first switching element and the second switching element on, and turns the bidirectional switching element on in an off period of the first switching element or the second switching element. Thus, the inverter device outputs an alternating current output voltage by using a single secondary winding of a transformer.
    Type: Application
    Filed: April 16, 2014
    Publication date: August 14, 2014
    Applicant: MURATA MANUFACTURING CO., LTD.
    Inventor: Hajime SHIJI
  • Publication number: 20140098574
    Abstract: A switching power supply includes a series resonant circuit that includes a resonant inductor and a resonant capacitor connected in series with a primary winding of a converter transformer. By controlling turning on and off of first and second switching elements in a complementary manner, current is supplied to the series resonant circuit. A third switching element connected on the secondary side of the converter transformer is synchronized with the first switching element, and a fourth switching element is synchronized with the second switching element. If a switching frequency is less than a resonant frequency, turning on of the third and fourth switching elements is synchronized with turning on of the first and second switching elements, and turning off of the third and fourth switching elements is controlled, without being synchronized with turning off of the first and second switching elements, after half a resonant period has elapsed.
    Type: Application
    Filed: October 10, 2013
    Publication date: April 10, 2014
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Takashi HARA, Hajime SHIJI
  • Publication number: 20130336017
    Abstract: A resonant converter circuit generates an output voltage from an input voltage by switching first and second FETs. A subsequent-stage switching control circuit alternately subjects the first and second FETs in the resonant converter circuit to on/off control with a fixed on-duty ratio and a fixed switching frequency. A boost converter circuit includes an inductor, a smoothing capacitor, and a third FET arranged to switch the energization of the inductor. A previous-stage switching control circuit subjects the third FET in the boost converter circuit to on/off control with a controlled on-duty ratio, and adjusts an output voltage to the resonant converter circuit.
    Type: Application
    Filed: June 5, 2013
    Publication date: December 19, 2013
    Inventors: Yoshiyuki UNO, Hajime SHIJI
  • Publication number: 20130336016
    Abstract: A half-bridge converter circuit generates an output voltage from an input voltage, by switching first and second FETs. A subsequent-stage switching control circuit alternately subjects the first and second FETs in the half-bridge converter circuit to on/off control with a fixed on-duty ratio and with a switching frequency corresponding to the weight of a load and a dead time sandwiched therebetween. A boost converter circuit includes an inductor, a smoothing capacitor, and a third FET switching the energization of the inductor. A previous-stage switching control circuit subjects the third FET in the boost converter circuit to on/off control with a controlled on-duty ratio, and adjusts the output voltage of the half-bridge converter circuit.
    Type: Application
    Filed: June 5, 2013
    Publication date: December 19, 2013
    Inventor: Hajime SHIJI