Patents by Inventor Tomoki Hikichi

Tomoki Hikichi 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).

  • Patent number: 8305075
    Abstract: Provided is a magnetic sensor circuit of low power consumption, in which a magnetic detection level less depends on a resistance value of an internal resistor of a power source. A comparator circuit compares a voltage which is based on a magnetic field and generated after sampling under a state in which power is supplied to mainly a Hall element and an amplifier circuit to drop a power supply voltage, with a reference voltage after sampling under the same state. Both the voltages are generated based on the power supply voltage dropped by an internal resistor. Therefore, the magnetic detection level less depends on a resistance value of the internal resistor. The comparator circuit may be disabled during a sample period, and the Hall element and the amplifier circuit may be disabled during a comparison period, and hence power consumption of the magnetic sensor circuit is reduced by corresponding power.
    Type: Grant
    Filed: September 27, 2010
    Date of Patent: November 6, 2012
    Assignee: Seiko Instruments Inc.
    Inventors: Tomoki Hikichi, Minoru Ariyama
  • Patent number: 8207778
    Abstract: Provided is a physical quantity sensor capable of improving physical quantity detection precision thereof. The physical quantity sensor includes a bridge resistance type physical quantity detection element for generating a voltage based on a bias current and a physical quantity, a current supply circuit for supplying the bias current to the physical quantity detection element, and a leakage current control circuit for causing leakage currents flowing when switches of the current supply circuit are in an off state to flow into a ground terminal.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: June 26, 2012
    Assignee: Seiko Instruments Inc.
    Inventors: Manabu Fujimura, Minoru Ariyama, Daisuke Muraoka, Tomoki Hikichi
  • Patent number: 8193807
    Abstract: Provided is a magnetic sensor device including: a switching circuit that controls switching of a terminal pair of the magnetoelectric conversion element to which a supply voltage is applied and a terminal pair to which detection voltage of a magnetic intensity is output; a differential amplifier that differentially amplifies the detection voltage; a first capacitor connected to a first output terminal of the differential amplifier; a second switch connected to a second output terminal of the differential amplifier; a comparator that has a first input terminal connected to the first capacitor and a second input terminal connected to the second switch; a first switch connected between the first input terminal and an output terminal of the comparator; and a second capacitor connected to the second input terminal of the comparator; and a detection voltage setting circuit connected to the second capacitor, in which effects of respective offset voltages of the magnetoelectric conversion element, the amplifier, and
    Type: Grant
    Filed: May 13, 2010
    Date of Patent: June 5, 2012
    Assignee: Seiko Instruments Inc.
    Inventors: Daisuke Muraoka, Minoru Ariyama, Tomoki Hikichi, Manabu Fujimura
  • Publication number: 20110241662
    Abstract: Provided is a magnetic sensor device capable of suppressing a variation in determination for detection or canceling of a magnetic field intensity, which is caused by noise generated from respective constituent elements included in the magnetic sensor device and external noise, to thereby achieve high-precision magnetic reading. The magnetic sensor device includes: a first D-type flip-flop and a second D-type flip-flop each having an input terminal connected to an output terminal of a comparator; an XOR circuit having a first input terminal and a second input terminal which are connected to an output terminal of the first D-type flip-flop and an output terminal of the second D-type flip-flop, respectively; a selector circuit; and a third D-type flip-flop having an input terminal connected to an output terminal of the selector circuit.
    Type: Application
    Filed: November 30, 2010
    Publication date: October 6, 2011
    Inventors: Daisuke Muraoka, Minoru Ariyama, Tomoki Hikichi, Manabu Fujimura
  • Publication number: 20110133812
    Abstract: Provided is a physical quantity sensor capable of improving physical quantity detection precision thereof. The physical quantity sensor includes a bridge resistance type physical quantity detection element for generating a voltage based on a bias current and a physical quantity, a current supply circuit for supplying the bias current to the physical quantity detection element, and a leakage current control circuit for causing leakage currents flowing when switches of the current supply circuit are in an off state to flow into a ground terminal.
    Type: Application
    Filed: December 6, 2010
    Publication date: June 9, 2011
    Inventors: Manabu Fujimura, Minoru Ariyama, Daisuke Muraoka, Tomoki Hikichi
  • Publication number: 20110127989
    Abstract: Provided is a constant current circuit capable of low current consumption operation, which is prevented from repeating a start-up state and a zero steady state and entering an oscillating state when power is activated. When power is activated, until a node (A) reaches a start-up state, an excitation current is continued to be supplied to a node (B), to thereby reliably start up the constant current circuit in a short period of time without repeating the start-up state and the zero steady state.
    Type: Application
    Filed: November 30, 2010
    Publication date: June 2, 2011
    Inventors: Tomoki Hikichi, Minoru Ariyama, Daisuke Muraoka, Manabu Fujimura
  • Publication number: 20110074404
    Abstract: Provided is a magnetic sensor circuit of low power consumption, in which a magnetic detection level less depends on a resistance value of an internal resistor of a power source. A comparator circuit compares a voltage which is based on a magnetic field and generated after sampling under a state in which power is supplied to mainly a Hall element and an amplifier circuit to drop a power supply voltage, with a reference voltage after sampling under the same state. Both the voltages are generated based on the power supply voltage dropped by an internal resistor. Therefore, the magnetic detection level less depends on a resistance value of the internal resistor. The comparator circuit may be disabled during a sample period, and the Hall element and the amplifier circuit may be disabled during a comparison period, and hence power consumption of the magnetic sensor circuit is reduced by corresponding power.
    Type: Application
    Filed: September 27, 2010
    Publication date: March 31, 2011
    Inventors: Tomoki Hikichi, Minoru Ariyama
  • Publication number: 20100308815
    Abstract: Provided is a magnetic sensor device including: a switching circuit that controls switching of a terminal pair of the magnetoelectric conversion element to which a supply voltage is applied and a terminal pair to which detection voltage of a magnetic intensity is output; a differential amplifier that differentially amplifies the detection voltage; a first capacitor connected to a first output terminal of the differential amplifier; a second switch connected to a second output terminal of the differential amplifier; a comparator that has a first input terminal connected to the first capacitor and a second input terminal connected to the second switch; a first switch connected between the first input terminal and an output terminal of the comparator; and a second capacitor connected to the second input terminal of the comparator; and a detection voltage setting circuit connected to the second capacitor, in which effects of respective offset voltages of the magnetoelectric conversion element, the amplifier, and
    Type: Application
    Filed: May 13, 2010
    Publication date: December 9, 2010
    Inventors: Daisuke Muraoka, Minoru Ariyama, Tomoki Hikichi, Manabu Fujimura
  • Publication number: 20100201447
    Abstract: A radio-frequency circuit comprises a low-noise amplifier, an NMOS mixer for converting a radio-frequency signal output from the low-noise amplifier into an intermediate-frequency signal, a polyphase filter for removing image noises, and a PMOS mixer for converting the intermediate-frequency signal passed through the polyphase filter into a baseband signal.
    Type: Application
    Filed: April 21, 2010
    Publication date: August 12, 2010
    Applicant: SEMICONDUCTOR TECHNOLOGY ACADAMIC RESEARCH CENTER
    Inventors: Akira Hyogo, Satoshi Tanaka, Tetsuro Sawai, Kenichi Agawa, Hirotada Honma, Ryutaro Saito, Tomoki Hikichi, Keitaro Sekine
  • Patent number: 7459906
    Abstract: To detect a magnetic flux density of a magnetic field applied from an outside, a semiconductor magnetic sensor of the present invention includes: a transistor (MP101) formed on a side of one, side of a hall element (100), for driving the hall element (100), the transistor (MP101) having a drain connected to a terminal (C101) formed on the one side; a transistor (MP102) formed on the side of the one side and having a drain connected to a terminal (C102) formed on the one side; a transistor (MN101) formed on a side of another side opposite to the one side and having a drain connected to a terminal (C103) formed on the another side; a transistor (MN102) formed on the side of the another side and having a drain connected to a terminal (C104) formed on the another side.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: December 2, 2008
    Assignee: Seiko Instruments Inc.
    Inventor: Tomoki Hikichi
  • Publication number: 20080150522
    Abstract: To detect a magnetic flux density of a magnetic field applied from an outside, a semiconductor magnetic sensor of the present invention includes: a transistor (MP101) formed on a side of one, side of a hall element (100), for driving the hall element (100), the transistor (MP101) having a drain connected to a terminal (C101) formed on the one side; a transistor (MP102) formed on the side of the one side and having a drain connected to a terminal (C102) formed on the one side; a transistor (MN101) formed on a side of another side opposite to the one side and having a drain connected to a terminal (C103) formed on the another side; a transistor (MN102) formed on the side of the another side and having a drain connected to a terminal (C104) formed on the another side.
    Type: Application
    Filed: December 19, 2007
    Publication date: June 26, 2008
    Inventor: Tomoki Hikichi
  • Publication number: 20060194559
    Abstract: A radio-frequency circuit comprises a low-noise amplifier, an NMOS mixer for converting a radio-frequency signal output from the low-noise amplifier into an intermediate-frequency signal, a polyphase filter for removing image noises, and a PMOS mixer for converting the intermediate-frequency signal passed through the polyphase filter into a baseband signal.
    Type: Application
    Filed: February 15, 2006
    Publication date: August 31, 2006
    Applicant: SEMICONDUCTOR TECHNOLOGY ACADEMIC RESEARCH CENTER
    Inventors: Akira Hyogo, Satoshi Tanaka, Tetsuro Sawai, Kenichi Agawa, Hirotada Honma, Ryutaro Saito, Tomoki Hikichi, Keitaro Sekine