Patents Assigned to Littelfuse, Inc.
  • Patent number: 6510032
    Abstract: The present invention provides an integrated overvoltage and overcurrent circuit protection device for use in telecommunication circuits. The integrated protected circuit device combines an overcurrent device and a fuse and an overvoltage protection device such as a thyristor to respectively protect against overcurrent conditions and transient overvoltages. Integration of the two devices in a common package ensures proper coordination and matching of the components, reduces the final product cost and reduces the physical space required on a telecommunications circuit for overvoltage and overcurrent circuit protection.
    Type: Grant
    Filed: March 24, 2000
    Date of Patent: January 21, 2003
    Assignee: Littelfuse, Inc.
    Inventor: Stephen J. Whitney
  • Patent number: 6507264
    Abstract: A fuse element partially encapsulated in an arc-suppression material which can, in turn, be integrated along with a semiconductor device into a semiconductor package to provide overcurrent protection, as well as a method of integrating such a fuse along with a semiconductor device into a semiconductor package wherein the semiconductor package has a standard form factor based on the semiconductor device integrated within.
    Type: Grant
    Filed: August 28, 2000
    Date of Patent: January 14, 2003
    Assignee: Littelfuse, Inc.
    Inventor: Stephen J. Whitney
  • Patent number: 6452474
    Abstract: The invention is a housing for a blade fuse, and a blade fuse that uses that housing. The housing includes a first generally planar wall and a second generally planar wall. The first and the second generally planar walls each have an outer surface and an inner surface, and the inner surface of the first generally planar wall faces the inner surface of the second generally planar wall. Each of the generally planar walls has at least one rib extending from its inner surfaces. The one or more rib on the inner surface of the first generally planar wall extends towards, and is generally aligned with, the one or more corresponding rib on the inner surface of the second generally planar wall. These generally aligned rib sets form a gap, and the gap is sized so as to permit the close-fitting insertion of a fuse element between that gap.
    Type: Grant
    Filed: October 23, 2000
    Date of Patent: September 17, 2002
    Assignee: Littelfuse, Inc.
    Inventor: Seibang Oh
  • Patent number: 6407657
    Abstract: A metallic element for use with a blade fuse or other electrical component, and a blade fuse or other electrical component that includes that metallic element as one of its components. The fuse maybe mounted in a fuseholder having either male terminal receiving clips, or female terminal receiving clips. The metallic element includes two terminal portions, each made of a first prong and a second prong. The second prong is spaced apart from the first prong, and a fusible link is secured to each of the two terminal portions. The spaced apart first and second prongs together form a gap between them to ensure secure engagement of the first and second prongs with male terminal blade-receiving clips.
    Type: Grant
    Filed: February 3, 2000
    Date of Patent: June 18, 2002
    Assignee: Littelfuse, Inc.
    Inventor: Seibang Oh
  • Patent number: 6376774
    Abstract: A housing for an electrical overload protection cable assembly having a first cable, a second cable, a fusible link, and a protective housing. The protective housing has a first housing member and a second housing member. The first and second housing members each have a first end portion and a second end portion. The first and second housing members are coupled to form the protective housing having a channel extending from the first end to the second end. A first rib extends from the protective housing into the channel, and a second rib extends from the protective housing into the channel. The second rib is transverse to the first rib.
    Type: Grant
    Filed: March 7, 2000
    Date of Patent: April 23, 2002
    Assignee: Littelfuse Inc.
    Inventors: Seibang Oh, Carl S. Reid
  • Patent number: 6359227
    Abstract: A fusible link for a cable assembly is provided. The fusible link has a link segment having a first member extending transversely from the link segment, and a second member extending transversely from the link segment. A first end of the link segment engaging a first cable of the cable assembly, and a second end of the link segment engaging a second cable of the cable assembly. A method of manufacturing the fusible link is also provided.
    Type: Grant
    Filed: March 7, 2000
    Date of Patent: March 19, 2002
    Assignee: Littelfuse, Inc.
    Inventors: Seibang Oh, Cesario Herbias, Demetrios Thanopoulos, Jozef Philoteus Maria Johannes Jaspar
  • Patent number: 6334964
    Abstract: A thixotropic ink for use in manufacturing a varistor comprising the following constituents: a) zinc oxide, b) ceramic structure influencing additives including bismuth oxide, boric acid, boron oxide, chromium oxide, cobalt oxide, magnesium oxide and tin oxide, c) a grain growth influencing additive selected from the group consisting of antimony oxide, silicon dioxide and titanium dioxide, d) an organic solvent carrier, e) an organic viscosity influencing additive, and f) an organic binder. The composition may serve as a ceramic ink for use in the manufacture of multilayer varistors, especially using a screen printing process.
    Type: Grant
    Filed: July 14, 1999
    Date of Patent: January 1, 2002
    Assignee: Littelfuse, Inc.
    Inventors: Stephen P. Cowman, Derek A. Nicker, John M. Shreeve
  • Patent number: 6282072
    Abstract: The present invention is an electrical circuit protection device having a PTC element with a first common electrode affixed to a first surface of the PTC element and at least two second electrodes affixed to a second surface of the PTC element. The at least two second electrodes are physically separated from one another such that when the at least two second electrodes are connected to a source of electrical current, the current travels from the at least two second electrodes, respectively, through the PTC element, to the first common electrode.
    Type: Grant
    Filed: February 23, 1999
    Date of Patent: August 28, 2001
    Assignee: Littelfuse, Inc.
    Inventors: Anthony D. Minervini, Thinh K. Nguyen
  • Patent number: 6232144
    Abstract: A method of providing nickel barrier end terminations for a zinc oxide semiconductor device with exposed body surfaces and end terminal regions, in which the device is controllably reacted with a nickel plating solution only on an exposed end terminal region and thereafter provided with a final tin or tin-lead termination.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: May 15, 2001
    Assignee: Littelfuse, Inc.
    Inventor: Neil McLoughlin
  • Patent number: 6214685
    Abstract: A method of providing a semiconductor device with a selectively deposited inorganic electrically insulative layer, the device having exposed semiconductor surfaces and electrically conductive metal end terminations, in which the device is saturated in a phosphoric acid solution to form a phosphate layer on the exposed surfaces of the semiconductor but not on the metal end terminations. The device is thereafter plated by a conventional plating process and the plating is provided only on the end terminations.
    Type: Grant
    Filed: July 2, 1998
    Date of Patent: April 10, 2001
    Assignee: Littelfuse, Inc.
    Inventors: Caroline Clinton, Trevor R. Spalding, Andrew Mark Connell, John Barrett, James F. Rohan
  • Patent number: 6211554
    Abstract: An integrated circuit die having on board protection against electrical overstress (EOS) transients. A device having an integrated circuit die with an outer periphery and a functional die area. A plurality of conductive input/output pads are formed on the integrated circuit die. A first conductive guard rail is disposed on the integrated circuit die and forms a gap between each one of the input/output pads. A voltage variable material is disposed in the gaps between the conductive guard rail and the input/output pads. A plurality of electrical leads are electrically connected to a respective one of the plurality of conductive input/output pads. At normal operating voltages, the voltage variable material is non-conductive. However, in response to an EOS transient, the voltage variable material switches to a low resistance state, providing a conductive path between the conductive guard rail and the input/output pads.
    Type: Grant
    Filed: December 7, 1999
    Date of Patent: April 3, 2001
    Assignee: Littelfuse, Inc.
    Inventor: Stephen J. Whitney
  • Patent number: 6191928
    Abstract: The thin film, electrical device is an subminiature overvoltage circuit protection device in a surface mountable configuration for use in printed circuit board or thick film hybrid circuit technology. The surface mountable device (SMD) is designed to protect against electrostatic discharge (ESD) damage to electronic components. The circuit protection device comprises three material subassemblies. The first subassembly generally includes a substrate carrier, electrodes, and terminal pads for connecting the protection device 60 to a PC board. The second subassembly includes a voltage variable polymer material with nonlinear resistance characteristics, and the third subassembly includes a cover coat for protecting other elements of the circuit protection device.
    Type: Grant
    Filed: February 23, 1999
    Date of Patent: February 20, 2001
    Assignee: Littelfuse, Inc.
    Inventors: Louis Rector, Hugh M. Hyatt, Anthony Minervini, Robert Swensen, Andrew J. Neuhalfen, Andrew W. S. Elliott
  • Patent number: 6078245
    Abstract: A thin film surface-mountable fuse for protection against electrical overload. The fuse comprises a substrate, fusible link, a containment compound, and a pair of terminal pads. The fusible link is produced from a first conductive material and supported on the substrate. A diffusion bar of a second conductive material is deposited on a portion of the fusible link. The containment compound is also deposited over a portion of the fusible link. The containment compound inhibits migration of the diffusion bar along the fusible link during an electrical overload. The terminal pads are electrically connected to the fusible link and also supported by the substrate.
    Type: Grant
    Filed: December 17, 1998
    Date of Patent: June 20, 2000
    Assignee: Littelfuse, Inc.
    Inventors: Sandra E. Fritz, Anthony Minervini, Thomas Restis
  • Patent number: 6046665
    Abstract: An improved cable assembly for electrical overload protection, the cable assembly having a first cable, a second cable, a fusible link, and a protective housing. The first and second cables have a protective covering and an end portion extending past the protective covering. The fusible link is located between the first and second cables such that the end portions of the cables are electrically connected to opposing ends of the fusible link. The protective housing encases a portion of the fusible link, with an intermediate section of the protective housing being spaced away from a portion of the fusible link to form a cavity. The protective housing also engages a portion of the first and second cables to form a rigid interconnecting housing around the fusible link and portions of the first and second cables.
    Type: Grant
    Filed: January 19, 1999
    Date of Patent: April 4, 2000
    Assignee: Littelfuse, Inc.
    Inventors: Seibang Oh, Demetrios Thanopoulos
  • Patent number: 6043966
    Abstract: A printed circuit board assembly comprising a printed circuit board having a plurality of conductive traces deposited on a surface thereof to define a plurality of electrical circuit geometries. A plurality of thin film fuses are deposited on the printed circuit board, each fuse providing circuit protection to one of the plurality of conductive traces.
    Type: Grant
    Filed: May 13, 1999
    Date of Patent: March 28, 2000
    Assignee: Littelfuse, Inc.
    Inventors: David J Krueger, Andrew J. Neuhalfen
  • Patent number: 6023028
    Abstract: The thin film, circuit device is an subminiature overvoltage protection device in a surface mountable configuration for use in printed circuit board or thick film hybrid circuit technology. The surface mountable device (SMD) is designed to protect against electrostatic discharge (ESD) damage to electronic components.The circuit protection device includes three material subassemblies. The first subassembly generally includes a substrate carier, electrodes, and terminal pads for connecting the protection device 60 to a PC board. The second subassembly includes a voltage variable polymer material with non-linear characteristics, and the third subassembly includes a cover coat for protecting other elements of the circuit protection device.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: February 8, 2000
    Assignee: Littelfuse, Inc.
    Inventor: Andrew J. Neuhalfen
  • Patent number: 6002322
    Abstract: A thin film, surface-mounted fuse which comprises two material subassemblies. The first subassembly comprises a fusible link, its supporting substrate and terminal pads. The second subassembly comprises a protective, photoimageable layer which overlies the fusible link so as to provide protection from impacts and oxidation. The photoimageable layer is a low profile coating.
    Type: Grant
    Filed: May 5, 1998
    Date of Patent: December 14, 1999
    Assignee: Littelfuse, Inc.
    Inventors: David J. Krueger, Brian J. Bullock, Honorio S. Luciano
  • Patent number: 5977860
    Abstract: A surface-mount fuse for protecting a circuit, which includes a substrate having first and second surfaces, each surface having first, second, third, and fourth ends, the substrate also having first, second, third, and fourth sides. The fuse includes a metal strip attached to the first surface of the substrate with a layer of adhesive material, the layer of adhesive material being disposed between the metal strip and the first surface of the substrate, the metal strip having a first connection region, a second connection region, and a non-linear fuse link therebetween. The fuse further includes first and second wire leads, the first wire lead being conductively connected to the first connection region and horizontally projecting away from the first connection region, the second wire lead being conductively connected to the second connection region and horizontally projecting away from the second connection region, for connecting the fuse to the remainder of the circuit.
    Type: Grant
    Filed: February 21, 1997
    Date of Patent: November 2, 1999
    Assignee: Littelfuse, Inc.
    Inventors: Steven Francis Ulm, Jr., Edwin James Harris, IV, Matthew Michael Rybka
  • Patent number: 5974661
    Abstract: The thin film, circuit device is a subminiature overvoltage protection device in a surface mountable configuration for use in printed circuit board or thick film hybrid circuit technology. The surface mountable device (SMD) is designed to protect against electrostatic discharge (ESD) damage to electronic components.The circuit protection device comprises three material subassemblies. The first subassembly generally includes a substrate carrier, electrodes, and terminal pads for connecting the protection device to a PC board. The second subassembly includes a voltage variable polymer material with non-linear characteristics, and the third subassembly includes a cover coat for protecting the circuit protection device.
    Type: Grant
    Filed: January 20, 1998
    Date of Patent: November 2, 1999
    Assignee: Littelfuse, Inc.
    Inventor: Andrew J. Neuhalfen
  • Patent number: 5945903
    Abstract: A circuit protection device including a pair of terminals to be electrically connected into an electrical circuit, a pair of spaced current-carrying extensions of the terminals, and an initially low resistance current limiting device extending between the current-carrying extensions. The invention includes the feature that the current-limiting element including flexible conductive current-feeding arms having inner and outer end portions, the inner end portions thereof being electrically connected to the current-carrying extensions of the terminals. The outer end portions of the current-feeding arms are cantilevered and flexible relative to the inner end portions. The device further preferably includes a PTC current-limiting element sandwiched between the flexible outer end portions of the current-feeding arms.
    Type: Grant
    Filed: August 30, 1997
    Date of Patent: August 31, 1999
    Assignee: Littelfuse, Inc.
    Inventors: Nagi Reddi Kanamatha Reddy, Robert Swensen, Thomas F. Draho, Michael Styrna