Patents by Inventor Haruo Kawakita

Haruo Kawakita 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: 7819110
    Abstract: An ignition coil includes a coil portion and an igniter. The coil portion has a primary coil, a secondary coil, and a coil case. The primary coil and the secondary coil are disposed in the coil case. The igniter is disposed on one end side of the coil portion. The igniter includes a metallic frame connected to a voltage source at a constant potential, and a semiconductor integrated chip disposed on the metallic frame. The semiconductor integrated chip has a control circuit for controlling a switching element. The control circuit is formed by a dielectric isolation method. A surface of the semiconductor integrated chip on a silicon substrate-side is opposed to the metallic frame.
    Type: Grant
    Filed: January 15, 2008
    Date of Patent: October 26, 2010
    Assignee: Denso Corporation
    Inventors: Mitsunobu Niwa, Haruo Kawakita
  • Patent number: 7786606
    Abstract: A resin-sealed semiconductor device includes a metal frame, an electronic substrate, an adhesive agent, a molded resin, and a bonding agent. The electronic substrate includes a first surface having a circuit element wiring part, a second surface facing the metal frame, and a side surface arranged approximately perpendicularly to the first surface and the second surface. The adhesive agent is disposed between the metal frame and the second surface to cover the second surface and a portion of the side surface adjacent to the second surface. The molded resin covers the metal frame and the electronic substrate, and holds the other portion of the side surface adjacent to the first surface. The bonding agent is disposed between the circuit element wiring part and the molded resin so that the molded resin holds the circuit element wiring part through the bonding agent.
    Type: Grant
    Filed: November 27, 2007
    Date of Patent: August 31, 2010
    Assignee: Denso Corporation
    Inventors: Mitsuyasu Enomoto, Haruo Kawakita, Takashi Ohno
  • Patent number: 7530350
    Abstract: In an engine ignition system, an igniter for an ignition coil is connected to an ECU through a signal wire. The signal wire is grounded via the collector and the emitter of a bipolar transistor of an output circuit of the igniter. A constant current source outputs a current to the base of the bipolar transistor. Switching transistors are connected between the emitter and base of the bipolar transistor. When all the switching transistors are turned off, the bipolar transistor is turned on.
    Type: Grant
    Filed: May 31, 2007
    Date of Patent: May 12, 2009
    Assignee: DENSO Corporation
    Inventors: Takashi Oono, Haruo Kawakita
  • Patent number: 7528469
    Abstract: Semiconductor equipment includes: a first lead frame having a first semiconductor device; a second lead frame having a second semiconductor device; a thermal resistor for preventing heat transfer from the first lead frame to the second lead frame; and a temperature sensitive device for detecting operational temperature of the first semiconductor device. The first lead frame is separated from the second lead frame by a predetermined distance. The thermal resistor is disposed in a clearance between the first lead frame and the second lead frame. The second semiconductor device controls to restrict operation of the first semiconductor device when the operational temperature of the first semiconductor device is higher than a predetermined temperature.
    Type: Grant
    Filed: June 2, 2005
    Date of Patent: May 5, 2009
    Assignee: Denso Corporation
    Inventors: Haruo Kawakita, Koji Ando
  • Publication number: 20080180137
    Abstract: An ignition coil includes a coil portion and an igniter. The coil portion has a primary coil, a secondary coil, and a coil case. The primary coil and the secondary coil are disposed in the coil case. The igniter is disposed on one end side of the coil portion. The igniter includes a metallic frame connected to a voltage source at a constant potential, and a semiconductor integrated chip disposed on the metallic frame. The semiconductor integrated chip has a control circuit for controlling a switching element. The control circuit is formed by a dielectric isolation method. A surface of the semiconductor integrated chip on a silicon substrate-side is opposed to the metallic frame.
    Type: Application
    Filed: January 15, 2008
    Publication date: July 31, 2008
    Applicant: DENSO CORPORATION
    Inventors: Mitsunobu Niwa, Haruo Kawakita
  • Publication number: 20080128920
    Abstract: A resin-sealed semiconductor device includes a metal frame, an electronic substrate, an adhesive agent, a molded resin, and a bonding agent. The electronic substrate includes a first surface having a circuit element wiring part, a second surface facing the metal frame, and a side surface arranged approximately perpendicularly to the first surface and the second surface. The adhesive agent is disposed between the metal frame and the second surface to cover the second surface and a portion of the side surface adjacent to the second surface. The molded resin covers the metal frame and the electronic substrate, and holds the other portion of the side surface adjacent to the first surface. The bonding agent is disposed between the circuit element wiring part and the molded resin so that the molded resin holds the circuit element wiring part through the bonding agent.
    Type: Application
    Filed: November 27, 2007
    Publication date: June 5, 2008
    Applicant: DENSO CORPORATION
    Inventors: Mitsuyasu Enomoto, Haruo Kawakita, Takashi Ohno
  • Patent number: 7341052
    Abstract: A power switching control device for electric systems such as an ignition device for internal combustion engines has a control circuit IC and a switching IC. A temperature sensor is provided in the switching IC. The control circuit IC is joined to a grounding terminal through a conductive layer provided therebetween. Thus, the substrate potential of the control circuit IC is stabilized to the ground potential so that the temperature sensor is prohibited to operate erroneously due to electromagnetic noise.
    Type: Grant
    Filed: April 20, 2006
    Date of Patent: March 11, 2008
    Assignee: DENSO CORPORATION
    Inventor: Haruo Kawakita
  • Publication number: 20080006256
    Abstract: In an engine ignition system, an igniter for an ignition coil is connected to an ECU through a signal wire. The signal wire is grounded via the collector and the emitter of a bipolar transistor of an output circuit of the igniter. A constant current source outputs a current to the base of the bipolar transistor. Switching transistors are connected between the emitter and base of the bipolar transistor. When all the switching transistors are turned off, the bipolar transistor is turned on.
    Type: Application
    Filed: May 31, 2007
    Publication date: January 10, 2008
    Applicant: DENCO CORPORATION
    Inventors: Takashi Oono, Haruo Kawakita
  • Patent number: 7131436
    Abstract: An ignition system for an internal combustion engine is connected to an ignition coil and to a circuit for providing an ignition signal. The ignition system includes a switch circuit connected to the ignition coil that switches on or off current supplied to the ignition coil, a control circuit that controls the switch circuit based on the ignition signal and a protection circuit that includes a pair of back-to-back connected zener diodes connected between the input terminal of the control circuit and a ground.
    Type: Grant
    Filed: August 2, 2005
    Date of Patent: November 7, 2006
    Assignee: DENSO Corporation
    Inventors: Haruo Kawakita, Koji Ando
  • Patent number: 7131437
    Abstract: An ignition device for an internal combustion engine includes a power transistor connected to a primary coil of an ignition coil, a current sensing resistor connected in series with the power transistor, a constant current circuit and an abnormal oscillation control circuit that connects the gate resistor with the feedback circuit when the constant current circuit controls the primary current to be constant. The constant current circuit has a gate resistor connected in series to the control gate of the power transistor and a feedback circuit connected between the gate resistor and the current sensing resistor and controls current supplied to a control gate of the power transistor so as to control the primary current to be constant.
    Type: Grant
    Filed: May 2, 2005
    Date of Patent: November 7, 2006
    Assignee: DENSO Corporation
    Inventors: Koji Ando, Haruo Kawakita
  • Publication number: 20060244496
    Abstract: A power switching control device for electric systems such as an ignition device for internal combustion engines has a control circuit IC and a switching IC. A temperature sensor is provided in the switching IC. The control circuit IC is joined to a grounding terminal through a conductive layer provided therebetween. Thus, the substrate potential of the control circuit IC is stabilized to the ground potential so that the temperature sensor is prohibited to operate erroneously due to electromagnetic noise.
    Type: Application
    Filed: April 20, 2006
    Publication date: November 2, 2006
    Applicant: DENSO CORPORATION
    Inventor: Haruo Kawakita
  • Patent number: 7095182
    Abstract: An ignition control apparatus for an internal combustion engine of the present invention has a switching circuit and a control circuit. The switching circuit includes a first switch controlling a main current constituting the most portion of the coil current, a second switch controlling a sensing current constituting the coil current together with the main current; and a temperature sensor detecting temperatures of the first and the second switches, which are realized by semiconductors. The control circuit, which is heat-isolated from the switching circuit, includes a current limiting circuit operating the first switch and the second switch to adjust the coil current to a predetermined value based on the sensing current, and a thermal shutoff circuit turning off both the first switch and the second switch when the temperature detected by the temperature sensor exceeds a predetermined threshold value.
    Type: Grant
    Filed: December 9, 2004
    Date of Patent: August 22, 2006
    Assignee: Denso Corporation
    Inventors: Koji Ando, Haruo Kawakita
  • Publication number: 20060027220
    Abstract: An ignition system for an internal combustion engine is connected to an ignition coil and to a circuit means for providing an ignition signal. The ignition system includes a switch circuit connected to the ignition coil that switches on or off current supplied to the ignition coil, a control circuit that controls the switch circuit based on the ignition signal and a protection circuit that includes a pair back-to-back connected zener diodes connected between the input terminal of the control circuit and a ground.
    Type: Application
    Filed: August 2, 2005
    Publication date: February 9, 2006
    Applicant: Denso Corporation
    Inventors: Haruo Kawakita, Koji Ando
  • Publication number: 20050269674
    Abstract: Semiconductor equipment includes: a first lead frame having a first semiconductor device; a second lead frame having a second semiconductor device; a thermal resistor for preventing heat transfer from the first lead frame to the second lead frame; and a temperature sensitive device for detecting operational temperature of the first semiconductor device. The first lead frame is separated from the second lead frame by a predetermined distance. The thermal resistor is disposed in a clearance between the first lead frame and the second lead frame. The second semiconductor device controls to restrict operation of the first semiconductor device when the operational temperature of the first semiconductor device is higher than a predetermined temperature.
    Type: Application
    Filed: June 2, 2005
    Publication date: December 8, 2005
    Applicant: DENSO CORPORATION
    Inventors: Haruo Kawakita, Koji Ando
  • Publication number: 20050252496
    Abstract: An ignition device for an internal combustion engine includes a power transistor connected to a primary coil of an ignition coil, a current sensing resistor connected in series with the power transistor, a constant current circuit and an abnormal oscillation control circuit that connects the gate resistor with the feedback circuit when the constant current circuit controls the primary current to be constant. The constant current circuit has a gate resistor connected in series to the control gate of the power transistor and a feedback circuit connected between the gate resistor and the current sensing resistor and controls current supplied to a control gate of the power transistor so as to control the primary current to be constant.
    Type: Application
    Filed: May 2, 2005
    Publication date: November 17, 2005
    Applicant: DENSO CORPORATION
    Inventors: Koji Ando, Haruo Kawakita
  • Publication number: 20050146822
    Abstract: An ignition control apparatus for an internal combustion engine of the present invention has a switching circuit and a control circuit. The switching circuit includes a first switch controlling a main current constituting the most portion of the coil current, a second switch controlling a sensing current constituting the coil current together with the main current; and a temperature sensor detecting temperatures of the first and the second switches, which are realized by semiconductors. The control circuit, which is heat-isolated from the switching circuit, includes a current limiting circuit operating the first switch and the second switch to adjust the coil current to a predetermined value based on the sensing current, and a thermal shutoff circuit turning off both the first switch and the second switch when the temperature detected by the temperature sensor exceeds a predetermined threshold value.
    Type: Application
    Filed: December 9, 2004
    Publication date: July 7, 2005
    Applicant: DENSO CORPORATION
    Inventors: Koji Ando, Haruo Kawakita
  • Patent number: 6765266
    Abstract: In a semiconductor device of the present invention, a first semiconductor region is formed so that a peripheral edge thereof is located between a first field plate ring that corresponds to one of field plate rings located at the innermost side thereof and a second field plate ring that corresponds to one of the field plate rings adjacent the first plate ring. Accordingly, when a surge voltage is applied to the semiconductor device of the present invention, an electric field concentration at a part of the isolation film located under the first one of the field plate rings is relaxed and an electric field intensity decreases. Therefore, the reliability of the isolation film for withstanding the surge voltage increases.
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: July 20, 2004
    Assignee: Denso Corporation
    Inventors: Yoshihiko Ozeki, Yutaka Tomatsu, Norihito Tokura, Haruo Kawakita
  • Publication number: 20030107102
    Abstract: In a semiconductor device of the present invention, a first semiconductor region is formed so that a peripheral edge thereof is located between a first field plate ring that corresponds to one of field plate rings located at the innermost side thereof and a second field plate ring that corresponds to one of the field plate rings adjacent the first plate ring. Accordingly, when a surge voltage is applied to the semiconductor device of the present invention, an electric field concentration at a part of the isolation film located under the first one of the field plate rings is relaxed and an electric field intensity decreases. Therefore, the reliability of the isolation film for withstanding the surge voltage increases.
    Type: Application
    Filed: December 3, 2002
    Publication date: June 12, 2003
    Inventors: Yoshihiko Ozeki, Yutaka Tomatsu, Norihito Tokura, Haruo Kawakita
  • Patent number: 6452219
    Abstract: An IGBT having a buffer layer for shortening the turn-off time and for preventing the latching up is improved. The buffer layer of the present invention is not bare at the edge of a diced cross-section of the IGBT chip. According to this construction, a withstanding voltage between a semiconductor substrate and the buffer layer is lower than the withstand voltage of the pn junction at the edge of the diced cross-section. Therefore, the whole pn junction between the semiconductor substrate and the buffer layer, which has wide area, breaks down, as a result, energy caused by a negative voltage is absorbed, and the withstanding voltage against the negative voltage is improved.
    Type: Grant
    Filed: August 26, 1997
    Date of Patent: September 17, 2002
    Assignee: Denso Corporation
    Inventors: Yoshiyuki Miyase, Naohito Kato, Haruo Kawakita, Naoto Okabe
  • Patent number: 5801445
    Abstract: A semiconductor device has an electrode interposed between an interlayer insulation film and a wire which is bonded thereto. A main component of the electrode is aluminum and the electrode contains fine-grained silicon in a concentration of 0.1 to 0.6 weight %. As a result, even if large ultrasonic power, a large load or the like is applied to the electrode when the wire is wire-bonded, damage such as the formation of a crack hardly generates at the interlayer insulation film. Therefore, the occurrence of defects due to the wire-bonding can be reduced.
    Type: Grant
    Filed: March 14, 1997
    Date of Patent: September 1, 1998
    Assignee: Denso Corporation
    Inventors: Yasuo Ishihara, Haruo Kawakita, Naoto Okabe