Patents by Inventor Kazuyoshi Futamura
Kazuyoshi Futamura 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: 11362667Abstract: A device includes a master delay-lock loop (DLL) having a phase frequency detector connected in series with a charge pump that is to generate a control voltage. A slave DLL is coupled to the master DLL and has a delay line including a buffer to receive a slave clock and a series of delay cells coupled between the buffer and an output terminal that is to output a delay clock, the series of delay cells variably controlled by the control voltage. The master DLL and the slave DLL are powered by a power supply that experiences undershoot or overshoot in response to a load transient. A dummy load is coupled between the delay line of the slave DLL and an output of the power supply, the dummy load including an exclusive OR gate that receives, as inputs, a first output of the buffer and the delay clock.Type: GrantFiled: September 24, 2021Date of Patent: June 14, 2022Assignee: Cypress Semiconductor CorporationInventors: Kazuyoshi Futamura, Kazuhiro Tomita, Koji Okada, Hiroyuki Matsunami
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Patent number: 9035632Abstract: A DC-DC converter includes a first amplifier that amplifies a first difference between a first reference voltage and a feedback voltage corresponding to an output voltage, a second amplifier that amplifies a second difference between the first reference voltage and an integrated value of the feedback voltage, and a controller that controls a switching circuit to change the output voltage when the first difference reaches the second different.Type: GrantFiled: July 28, 2010Date of Patent: May 19, 2015Assignee: Cypress Semiconductor CorporationInventor: Kazuyoshi Futamura
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Patent number: 8988052Abstract: A control circuit for controlling a power supply including a first switch and a second switch coupled in series between a first potential and a second potential. The control circuit includes a detection circuit that detects a magnitude relation of a voltage value at a node between the first and second switches and a reference value during a period in which the first switch and the second switch are inactivated. The detection circuit generates a control signal corresponding to the magnitude relation. A regulation circuit regulates a switching timing of the second switch in response to the control signal to decrease a difference between the voltage value at the node and the reference value.Type: GrantFiled: April 15, 2011Date of Patent: March 24, 2015Assignee: Spansion LLCInventors: Kazuyoshi Futamura, Takashi Matsumoto, Ryuta Nagai
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Patent number: 8823344Abstract: A control circuit arranged in a power supply including first and second switches to control an output voltage of the power supply. The control circuit includes a first control circuit that switches the first and second switches in a complementary manner in accordance with a comparison result of a first reference voltage and a feedback voltage corresponding to the output voltage of the power supply. A first comparison circuit compares the output voltage or feedback voltage with a second reference value. A second comparison circuit compares a coupling point current flowing through a coupling point between the first and second switches with a third reference value. A second control circuit disables complementary switching of the first and second switches in accordance with an output signal from the first comparison circuit and enables the complementary switching in accordance with an output signal of the second comparison circuit.Type: GrantFiled: December 16, 2011Date of Patent: September 2, 2014Assignee: Spansion LLCInventors: Koichiro Kushida, Kazuyoshi Futamura, Masao Kumagai
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Patent number: 8698465Abstract: A control circuit for controlling a power supply including a first switch and a second switch coupled in series between a first potential and a second potential. The control circuit includes a detection circuit that detects a magnitude relation of a voltage value at a node between the first and second switches and a reference value during a period in which the first switch and the second switch are inactivated. The detection circuit generates a control signal corresponding to the magnitude relation. A regulation circuit regulates a switching timing of the second switch in response to the control signal to decrease a difference between the voltage value at the node and the reference value.Type: GrantFiled: April 15, 2011Date of Patent: April 15, 2014Assignee: Spansion LLCInventors: Kazuyoshi Futamura, Takashi Matsumoto, Ryuta Nagai
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Patent number: 8344711Abstract: A power supply device including a converter having a switch circuit to which an input voltage is supplied and a coil coupled between the switch circuit and an output end from which an output voltage is output; and a control circuit comparing between a feedback voltage and a reference voltage, and on/off controls the switch circuit according to a comparison result; wherein, the control circuit includes a current gradient detection circuit performs detection of a gradient of a coil current flows thorough the coil during an off period of the switch circuit and generates a slope voltage according to a result of the detection; and an adder circuit performs one of generating the feedback voltage by adding the slope voltage to a voltage according to the output voltage and generating the reference voltage by adding the slope voltage to a standard voltage that is set according to the output voltage.Type: GrantFiled: April 19, 2010Date of Patent: January 1, 2013Assignee: Fujitsu Semiconductor LimitedInventor: Kazuyoshi Futamura
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Publication number: 20120212195Abstract: A control circuit arranged in a power supply including first and second switches to control an output voltage of the power supply. The control circuit includes a first control circuit that switches the first and second switches in a complementary manner in accordance with a comparison result of a first reference voltage and a feedback voltage corresponding to the output voltage of the power supply. A first comparison circuit compares the output voltage or feedback voltage with a second reference value. A second comparison circuit compares a coupling point current flowing through a coupling point between the first and second switches with a third reference value. A second control circuit disables complementary switching of the first and second switches in accordance with an output signal from the first comparison circuit and enables the complementary switching in accordance with an output signal of the second comparison circuit.Type: ApplicationFiled: December 16, 2011Publication date: August 23, 2012Applicant: FUJITSU SEMICONDUCTOR LIMITEDInventors: Koichiro Kushida, Kazuyoshi Futamura, Masao Kumagai
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Publication number: 20120025797Abstract: A control circuit for controlling a power supply including a first switch and a second switch coupled in series between a first potential and a second potential. The control circuit includes a detection circuit that detects a magnitude relation of a voltage value at a node between the first and second switches and a reference value during a period in which the first switch and the second switch are inactivated. The detection circuit generates a control signal corresponding to the magnitude relation. A regulation circuit regulates a switching timing of the second switch in response to the control signal to decrease a difference between the voltage value at the node and the reference value.Type: ApplicationFiled: April 15, 2011Publication date: February 2, 2012Applicant: FUJITSU SEMICONDUCTOR LIMITEDInventors: Kazuyoshi FUTAMURA, Takashi MATSUMOTO, Ryuta NAGAI
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Publication number: 20110025283Abstract: A DC-DC converter includes a first amplifier that amplifies a first difference between a first reference voltage and a feedback voltage corresponding to an output voltage, a second amplifier that amplifies a second difference between the first reference voltage and an integrated value of the feedback voltage, and a controller that controls a switching circuit to change the output voltage when the first difference reaches the second different.Type: ApplicationFiled: July 28, 2010Publication date: February 3, 2011Applicant: FUJITSU SEMICONDUCTOR LIMITEDInventor: Kazuyoshi FUTAMURA
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Publication number: 20100283440Abstract: A power supply device including a converter having a switch circuit to which an input voltage is supplied and a coil coupled between the switch circuit and an output end from which an output voltage is output; and a control circuit comparing between a feedback voltage and a reference voltage, and on/off controls the switch circuit according to a comparison result; wherein, the control circuit includes a current gradient detection circuit performs detection of a gradient of a coil current flows thorough the coil during an off period of the switch circuit and generates a slope voltage according to a result of the detection; and an adder circuit performs one of generating the feedback voltage by adding the slope voltage to a voltage according to the output voltage and generating the reference voltage by adding the slope voltage to a standard voltage that is set according to the output voltage.Type: ApplicationFiled: April 19, 2010Publication date: November 11, 2010Applicant: FUJITSU MICROELECTRONICS LIMITEDInventor: Kazuyoshi Futamura