Patents by Inventor Takayuki Iwasaki

Takayuki Iwasaki 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: 7019362
    Abstract: The gate resistance of a power MOSFET in a semiconductor chip is reduced and the reliability and yield of the gate of the power MOSFET are improved The semiconductor chip includes two or more control electrode pads functioning as control electrodes for a power semiconductor device formed within a semiconductor chip. The two or more control electrode pads are distributed within the periphery of the gate area of the power semiconductor device such that the gate resistance of the power semiconductor device can be reduced. The two or more control electrode pads are connected via bumps or a conductive bonding material to an electrode layer of a multilayer circuit board disposed outside the semiconductor chip.
    Type: Grant
    Filed: February 20, 2004
    Date of Patent: March 28, 2006
    Assignee: Renesas Technology, Corp.
    Inventors: Kozo Sakamoto, Takayuki Iwasaki, Masaki Shiraishi
  • Patent number: 7005834
    Abstract: In a power supply of a synchronous rectification type, the self-turn on phenomenon of MOSFET is suppressed without increase of the drive loss to thereby improve the power efficiency. In a synchronous rectifier circuit, a threshold value of a commutation MOSFET is made higher than that of a rectification MOSFET and particularly a threshold value of a commutation MOSFET 3 is made 0.5V or more higher than that of a rectification MOSFET 2. The threshold value of the rectification MOSFET 2 is lower than 1.5V and the threshold of the commutation MOSFET 3 is higher than 2.0V.
    Type: Grant
    Filed: July 2, 2004
    Date of Patent: February 28, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Takayuki Iwasaki, Kozo Sakamoto, Masaki Shiraishi, Nobuyoshi Matsuura, Tomoaki Uno
  • Publication number: 20060006432
    Abstract: A semiconductor device in which the self-turn-on phenomenon is prevented that can significantly improve power conversion efficiency. The semiconductor device is a system-in-package for power supply applications in which a high-side switch, a low-side switch, and two drivers are included in a single package. The device includes an auxiliary switch disposed between the gate and source of said low-side switch, and a low-side MOSFET 3 for the low-side switch and an auxiliary MOSFET 4 for the auxiliary switch are disposed on the same chip. In this way, the self-turn-on phenomenon can be prevented, allowing the mounting of a low-side MOSFET 3 with a low threshold voltage and thereby significantly improving power conversion efficiency. The gate of the auxiliary MOSFET 4 is driven by the driver for the high-side MOSFET 2, thereby eliminating the need for a new drive circuit and realizing the same pin configuration as existing products, which facilitates easy replacement.
    Type: Application
    Filed: July 7, 2005
    Publication date: January 12, 2006
    Inventors: Masaki Shiraishi, Takayuki Iwasaki, Nobuyoshi Matsuura
  • Patent number: 6886583
    Abstract: A canister vent valve mounting structure for a canister vent valve is configured to prevent center deviation when the canister vent valve is connected to the canister and enables the canister to be shared by different vehicle models. The canister vent valve includes a connecting pipe part that fits into an insertion hole formed in the canister. Several mating projections are arranged in the circumferential direction of the connecting pipe part such that they are formed on the outside circumference of the connecting pipe part near the tip thereof. Several notches into which mating projections can be inserted are formed in the inside circumferential surface of the insertion hole. The canister vent valve mounting structure between the canister and the canister vent valve is configured and arranged to retain the canister vent valve in at least two different orientations relative to the canister.
    Type: Grant
    Filed: February 14, 2003
    Date of Patent: May 3, 2005
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hideyuki Matsushima, Takayuki Iwasaki
  • Publication number: 20050044916
    Abstract: An apparatus for manufacturing a band plate has a rolling mill that includes a pair of upper and lower work rolls that roll a slab material having edge drop portions at both ends thereof, and a pair of backup rolls that contact non-rolling side surfaces of the pair of upper and lower work rolls, respectively to prevent the work rolls from being deformed. The work roll includes a reverse taper portion where a roll diameter gradually increases towards a barrel end portion thereof corresponding to the edge drop portion. The upper and lower work rolls are configured to be shiftable individually in the axial direction thereof. The backup roll includes an escape portion whose diameter gradually decreases towards an axial end thereof so as not to contact the reverse taper portion of the work roll, within a shifting range of the work roll.
    Type: Application
    Filed: July 8, 2004
    Publication date: March 3, 2005
    Applicant: Ishikawajima-Harima Heavy Industries Co., Ltd.
    Inventors: Hisashi Honjo, Takayuki Iwasaki
  • Publication number: 20050028575
    Abstract: A plate rolling mill includes a pair of work rolls that hold and press down a plate material therebetween, a plurality of backup rolls that prevent the work rolls from being deformed, and intermediate rolls each of which is disposed between the work roll and the backup roll so as to be shiftable. Each of the intermediate rolls has a contact roll portion that contacts with the backup roll, and an extension barrel portion that is connected to an end of the contact roll portion and does not contact the backup roll at any shifted position. The contact roll is formed to have a convex shape such that a convex center of the contact roll is positioned at a side of the extension barrel portion.
    Type: Application
    Filed: July 8, 2004
    Publication date: February 10, 2005
    Applicant: Ishikawajima-Harima Heavy Industries Co., Ltd.
    Inventors: Hisashi Honjo, Takayuki Iwasaki
  • Publication number: 20050007078
    Abstract: In a power supply of a synchronous rectification type, the self-turn on phenomenon of MOSFET is suppressed without increase of the drive loss to thereby improve the power efficiency. In a synchronous rectifier circuit, a threshold value of a commutation MOSFET is made higher than that of a rectification MOSFET and particularly a threshold value of a commutation MOSFET 3 is made 0.5V or more higher than that of a rectification MOSFET 2. The threshold value of the rectification MOSFET 2 is lower than 1.5V and the threshold of the commutation MOSFET 3 is higher than 2.0V.
    Type: Application
    Filed: July 2, 2004
    Publication date: January 13, 2005
    Inventors: Takayuki Iwasaki, Kozo Sakamoto, Masaki Shiraishi, Nobuyoshi Matsuura, Tomoaki Uno
  • Publication number: 20050006649
    Abstract: A static induction transistor includes a semiconductor substrate with an energy band gap greater than that of silicon, and the semiconductor substrate has a first gate region to which a gate electrode is connected; and a second gate region positioned within a first semiconductor region which becomes a drain region, and the first gate region is in contact with a second semiconductor region which becomes a source region. According to this construction, the OFF characteristics of the static induction transistor are improved.
    Type: Application
    Filed: April 15, 2004
    Publication date: January 13, 2005
    Inventors: Takayuki Iwasaki, Tsutomu Yatsuo, Hidekatsu Onose, Toshiyuki Oono
  • Publication number: 20040231365
    Abstract: The manufacturing method comprises: a softening step of softening a straight glass tube in a heating furnace; a moving and placing step of moving the softened glass tube so that the glass tube is placed on the top of the mandrel; and a winding step of winding the glass tube placed on the top of the mandrel around the periphery of the mandrel. The mandrel is disposed beneath the glass tube starting to get soft, and the glass tube being soft is perpendicularly lowered in order to be placed on the top of the mandrel. In the winding step, the winding speed Vr at which the glass tube is wound around the mandrel is higher than the moving speed Vs at which chuck units holding the ends of the glass tube move toward the mandrel.
    Type: Application
    Filed: March 31, 2004
    Publication date: November 25, 2004
    Inventors: Tatsuhiro Yabuki, Noriyuki Uchida, Takayuki Iwasaki, Shiro Iida
  • Publication number: 20040227163
    Abstract: The gate resistance of a power MOSFET in a semiconductor chip is reduced and the reliability and yield of the gate of the power MOSFET are improved The semiconductor chip includes two or more control electrode pads functioning as control electrodes for a power semiconductor device formed within a semiconductor chip. The two or more control electrode pads are distributed within the periphery of the gate area of the power semiconductor device such that the gate resistance of the power semiconductor device can be reduced. The two or more control electrode pads are connected via bumps or a conductive bonding material to an electrode layer of a multilayer circuit board disposed outside the semiconductor chip.
    Type: Application
    Filed: February 20, 2004
    Publication date: November 18, 2004
    Inventors: Kozo Sakamoto, Takayuki Iwasaki, Masaki Shiraishi
  • Publication number: 20040227547
    Abstract: A power MOS-FET is used as a high side switch transistor for a non-insulated DC/DC converter. An electrode section that serves as a source terminal of the power MOS-FET is connected to one outer lead and two outer leads via bonding wires respectively. The outer lead is an external terminal connected to a path for driving the gate. Each of the outer leads is an external terminal connected to a main current path. Owing to the connection of the main current path and the gate driving path in discrete form, the influence of parasitic inductance can be reduced and voltage conversion efficiency can be improved.
    Type: Application
    Filed: May 3, 2004
    Publication date: November 18, 2004
    Inventors: Masaki Shiraishi, Takayuki Iwasaki, Nobuyoshi Matsuura, Tomoaki Uno
  • Publication number: 20040079996
    Abstract: The number of design processes for fabricating semiconductor devices can be reduced by parallel connection of a plurality of unit bipolar transistors Qu that are completely electrically isolated from each other in a semiconductor layer of an SOI substrate 1 to form a bipolar transistor having a large current capacity.
    Type: Application
    Filed: October 21, 2003
    Publication date: April 29, 2004
    Applicant: Hitachi, Ltd. and Hitachi ULSI Systems Co., Ltd.
    Inventors: Yoichi Tamaki, Takayuki Iwasaki, Kousuke Tsuji, Chiyoshi Kamada
  • Patent number: 6662344
    Abstract: The number of design processes for fabricating semiconductor devices can be reduced by parallel connection of a plurality of unit bipolar transistors Qu that are completely electrically isolated from each other in a semiconductor layer of an SOI substrate 1 to form a bipolar transistor having a large current capacity.
    Type: Grant
    Filed: March 8, 2002
    Date of Patent: December 9, 2003
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Yoichi Tamaki, Takayuki Iwasaki, Kousuke Tsuji, Chiyoshi Kamada
  • Publication number: 20030168099
    Abstract: A canister vent valve mounting structure for a canister vent valve is configured to prevent center deviation when the canister vent valve is connected to the canister and enables the canister to be shared by different vehicle models. The canister vent valve includes a connecting pipe part that fits into an insertion hole formed in the canister. Several mating projections are arranged in the circumferential direction of the connecting pipe part such that they are formed on the outside circumference of the connecting pipe part near the tip thereof. Several notches into which mating projections can be inserted are formed in the inside circumferential surface of the insertion hole. The canister vent valve mounting structure between the canister and the canister vent valve is configured and arranged to retain the canister vent valve in at least two different orientations relative to the canister.
    Type: Application
    Filed: February 14, 2003
    Publication date: September 11, 2003
    Applicant: Nissan Motor Co., Ltd.
    Inventors: Hideyuki Matsushima, Takayuki Iwasaki
  • Publication number: 20030169808
    Abstract: A communication system is provided including a transceiver and an application controller to transmit and receive signals through the transceiver. An isolator which insulates and separates the transceiver and application controller includes primary and secondary side circuits insulated from each other on a substrate and a capacitive insulating means to transfer signals between the primary and second sides while insulating and separating the primary side circuit from the secondary side circuit.
    Type: Application
    Filed: March 4, 2003
    Publication date: September 11, 2003
    Inventors: Seigoh Yukutake, Yasuyuki Kojima, Minehiro Nemoto, Masatsugu Amishiro, Takayuki Iwasaki, Shinichiro Mitani, Katsuhiro Furukawa, Chiyoshi Kamada, Atsuo Watanabe, Takayuki Oouchi, Nobuyasu Kanekawa
  • Patent number: 6603807
    Abstract: An isolator is made monolithic by forming a capacitive insulating barrier using an interlayer insulation film on the semiconductor substrate to miniaturize the modem device by the monolithic isolator.
    Type: Grant
    Filed: February 26, 1999
    Date of Patent: August 5, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Seigoh Yukutake, Yasuyuki Kojima, Minehiro Nemoto, Masatsugu Amishiro, Takayuki Iwasaki, Shinichiro Mitani, Katsuhiro Furukawa, Chiyoshi Kamada, Atsuo Watanabe, Takayuki Oouchi, Nobuyasu Kanekawa
  • Publication number: 20020190285
    Abstract: The on-resistance per chip area of a horizontal power MOSFET is reduced. In the horizontal power MOSFET in accordance with the present invention, low resistance penetrating conductive zones penetrating from a semiconductor surface in a p-type semiconductor zone on a low resistance p-type semiconductor substrate connected to an outer source electrode up to the p-type semiconductor zone are formed, and two or more n-type drain zones electrically connected to drain electrodes are formed in a semiconductor zone surrounded by the low resistance penetrating conductive zones, and an outer drain zone is provided on an active zone.
    Type: Application
    Filed: July 3, 2002
    Publication date: December 19, 2002
    Inventors: Kozo Sakamoto, Eiji Yanokura, Masaki Shiraishi, Takayuki Iwasaki
  • Publication number: 20020179945
    Abstract: The on-resistance per chip area of a horizontal power MOSFET is reduced.
    Type: Application
    Filed: February 8, 2002
    Publication date: December 5, 2002
    Inventors: Kozo Sakamoto, Eiji Yanokura, Masaki Shiraishi, Takayuki Iwasaki
  • Patent number: 6476750
    Abstract: The hardware of an over-sampling A/D and D/A converter is provided, which hardware is capable of being operated with either kind of software: one corresponding to a first method in which the over-sampling ratio is fixed and the other corresponding to a second method in which the over-sampling ratio is variable. The value N3 written on the pseudo-frequency-dividing-ratio-register 11 and the value N4 written on the pseudo-over-sampling-ratio-register 21 are converted through a user interface into the frequency dividing ratio N1 by the conversion circuit 12 and the converted result is written in the frequency-dividing-ratio-register 10.
    Type: Grant
    Filed: February 9, 2000
    Date of Patent: November 5, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Nobuyasu Kanekawa, Yasuyuki Kojima, Seigou Yukutake, Minehiro Nemoto, Kazuhisa Takami, Takayuki Iwasaki, Yusuke Takeuchi, Katsuhiro Furukawa
  • Publication number: 20020149084
    Abstract: The number of design processes for fabricating semiconductor devices can be reduced by parallel connection of a plurality of unit bipolar transistors Qu that are completely electrically isolated from each other in a semiconductor layer of an SOI substrate 1 to form a bipolar transistor having a large current capacity.
    Type: Application
    Filed: March 8, 2002
    Publication date: October 17, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Yoichi Tamaki, Takayuki Iwasaki, Kousuke Tsuji, Chiyoshi Kamada