Patents by Inventor Hisato HOSOYAMA
Hisato HOSOYAMA 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).
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Patent number: 9893629Abstract: A control method for a switching power supply circuit, the control method causing a processor to execute a process, the process includes: calculating a differential value between an output voltage of the switching power supply circuit and a target voltage; multiplying the differential value by a first coefficient to calculate a correction value; correcting a first detection value of an output current of the switching power supply circuit, which is detected by a current transformer circuit, based on the correction value, to generate a second detection value; comparing the second detection value with a threshold current value to determine whether or not an overcurrent has occurred; and reducing, when it is determined that the overcurrent has occurred, the output voltage of the switching power supply circuit.Type: GrantFiled: September 23, 2016Date of Patent: February 13, 2018Assignee: FUJITSU LIMITEDInventors: Yu Yonezawa, Tomotake Sasaki, Hisato Hosoyama, Yoshiyasu Nakashima
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Patent number: 9774249Abstract: A power supply apparatus includes: an inductor to which an input voltage is applied; a switching element that switches a current flowing to the inductor on and off so as to cause an induced voltage to be generated; an electrolytic capacitor that smoothes the induced voltage and outputs the voltage to a load; and a control circuit that controls the switching element, wherein the control circuit outputs a second switching control signal obtained by superimposing a degradation detection-purpose signal for detecting degradation of the electrolytic capacitor on a first control signal, detects an output voltage output by switching performed by the switching element controlled by the second control signal, and estimates the degradation of the electrolytic capacitor by using the output voltage detected, a duty cycle of the first control signal, and a frequency component of the degradation detection-purpose signal contained in the output voltage detected.Type: GrantFiled: June 23, 2015Date of Patent: September 26, 2017Assignee: FUJITSU LIMITEDInventors: Yoshinobu Matsui, Hisato Hosoyama, Tomotake Sasaki
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Patent number: 9768692Abstract: A power supply device comprising: a switching power supply unit which operates in accordance with a PWM signal; and a controller configured to generate the PWM signal, the controller includes: a switching frequency control unit configured to generate a spreading spectrum signal whose period is changed, an output voltage detecting unit configured to detect an output voltage of the switching power supply unit, a reference voltage unit configured to generate a reference voltage, a difference computing unit configured to calculate a difference between the output voltage and the reference voltage, a compensator configured to generate a compensating value from an input voltage of the switching power supply unit, the reference voltage, and the period of the spreading spectrum signal, and a PWM generator configured to generate the PWM signal from the spreading spectrum signal and the compensating value.Type: GrantFiled: April 22, 2015Date of Patent: September 19, 2017Assignee: FUJITSU LIMITEDInventor: Hisato Hosoyama
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Patent number: 9742284Abstract: A power circuit includes: first and second switching circuits coupled in parallel between an input terminal and an output terminal; a control signal generator that performs an ON/OFF control of the first and second switching circuits individually and generates a first control signal and a second control signal having different phases; a frequency converter that converts a frequency of the first control signal after converting a frequency of the second control signal; and a phase shifter that shifts the phase of the second control signal when a first interrupt is introduced as the first control signal is turned ON after the frequency converter has converted the frequency of the second control signal.Type: GrantFiled: September 18, 2015Date of Patent: August 22, 2017Assignee: FUJITSU LIMITEDInventors: Hisato Hosoyama, Tomotake Sasaki, Yu Yonezawa
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Publication number: 20170099003Abstract: A control method for a switching power supply circuit, the control method causing a processor to execute a process, the process includes: calculating a differential value between an output voltage of the switching power supply circuit and a target voltage; multiplying the differential value by a first coefficient to calculate a correction value; correcting a first detection value of an output current of the switching power supply circuit, which is detected by a current transformer circuit, based on the correction value, to generate a second detection value; comparing the second detection value with a threshold current value to determine whether or not an overcurrent has occurred; and reducing, when it is determined that the overcurrent has occurred, the output voltage of the switching power supply circuit.Type: ApplicationFiled: September 23, 2016Publication date: April 6, 2017Applicant: FUJITSU LIMITEDInventors: Yu Yonezawa, Tomotake Sasaki, Hisato HOSOYAMA, YOSHIYASU NAKASHIMA
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Publication number: 20160105114Abstract: A power circuit includes: first and second switching circuits coupled in parallel between an input terminal and an output terminal; a control signal generator that performs an ON/OFF control of the first and second switching circuits individually and generates a first control signal and a second control signal having different phases; a frequency converter that converts a frequency of the first control signal after converting a frequency of the second control signal; and a phase shifter that shifts the phase of the second control signal when a first interrupt is introduced as the first control signal is turned ON after the frequency converter has converted the frequency of the second control signal.Type: ApplicationFiled: September 18, 2015Publication date: April 14, 2016Applicant: Fujitsu LimitedInventors: Hisato HOSOYAMA, Tomotake Sasaki, Yu Yonezawa
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Publication number: 20160087555Abstract: An RCP (Rapid Control Prototyping) system for controlling a power supply apparatus, the RCP system includes: a computer; an MPU; and a bridge configured to connect the computer and the MPU and transfer data between the computer and the MPU using DMA, wherein the MPU is configured to generate an AD value from a signal of the power supply apparatus according to a switching period of the power supply apparatus, instruct to transfer the generated AD value to the computer using DMA via the bridge, and control the power supply apparatus according to a compensation value transferred using DMA via the bridge, and the computer is configured to instruct to transfer the compensation value calculated based on the AD value transferred through the last DMA to the MPU using DMA via the bridge and calculate the compensation value based on the AD value newly transferred using DMA.Type: ApplicationFiled: August 27, 2015Publication date: March 24, 2016Applicant: FUJITSU LIMITEDInventors: Hisato HOSOYAMA, Yu Yonezawa, Tomotake Sasaki
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Publication number: 20160006347Abstract: A power supply apparatus includes: an inductor to which an input voltage is applied; a switching element that switches a current flowing to the inductor on and off so as to cause an induced voltage to be generated; an electrolytic capacitor that smoothes the induced voltage and outputs the voltage to a load; and a control circuit that controls the switching element, wherein the control circuit outputs a second switching control signal obtained by superimposing a degradation detection-purpose signal for detecting degradation of the electrolytic capacitor on a first control signal, detects an output voltage output by switching performed by the switching element controlled by the second control signal, and estimates the degradation of the electrolytic capacitor by using the output voltage detected, a duty cycle of the first control signal, and a frequency component of the degradation detection-purpose signal contained in the output voltage detected.Type: ApplicationFiled: June 23, 2015Publication date: January 7, 2016Applicant: Fujitsu LimitedInventors: Yoshinobu MATSUI, Hisato HOSOYAMA, Tomotake SASAKI
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Publication number: 20150349639Abstract: A power supply device comprising: a switching power supply unit which operates in accordance with a PWM signal; and a controller configured to generate the PWM signal, the controller includes: a switching frequency control unit configured to generate a spreading spectrum signal whose period is changed, an output voltage detecting unit configured to detect an output voltage of the switching power supply unit, a reference voltage unit configured to generate a reference voltage, a difference computing unit configured to calculate a difference between the output voltage and the reference voltage, a compensator configured to generate a compensating value from an input voltage of the switching power supply unit, the reference voltage, and the period of the spreading spectrum signal, and a PWM generator configured to generate the PWM signal from the spreading spectrum signal and the compensating value.Type: ApplicationFiled: April 22, 2015Publication date: December 3, 2015Applicant: Fujitsu LimitedInventor: Hisato HOSOYAMA