Patents Assigned to Littelfuse, Inc.
  • Patent number: 10424915
    Abstract: Secondary battery protection circuits for protecting a battery from charging and/or discharging faults are provided. A secondary battery protection circuit may include a first terminal and a second terminal, a transistor electrically connected between the first terminal and the second terminal, a fuse electrically coupled to the gate of the transistor, and a fuse control circuit configured to cause current sufficient to open the fuse to pass through the fuse in the event of a fault condition.
    Type: Grant
    Filed: January 9, 2015
    Date of Patent: September 24, 2019
    Assignee: Littelfuse, Inc.
    Inventors: Sam S. Kang, John M. Jorgensen, Bharat Shenoy, Kunghao Yu
  • Patent number: 10424952
    Abstract: A bi-stage temperature device may include a low temperature component, comprising a negative temperature coefficient (NTC) material; and a high temperature component, mechanically coupled to the low temperature component, and comprising a positive temperature coefficient (PTC) material, and a flexible substrate. The low temperature component may be arranged to generate a low temperature transition, the low temperature transition comprising a first change in electrical resistance, from a first resistance to a second resistance at a first temperature. The high temperature component may be arranged to generate a high temperature transition, the high temperature transition comprising a second change in electrical resistance, from a third resistance to a fourth resistance at a second temperature.
    Type: Grant
    Filed: January 18, 2018
    Date of Patent: September 24, 2019
    Assignee: Littelfuse, Inc.
    Inventors: Weiqing Guo, Jianhua Chen
  • Publication number: 20190288499
    Abstract: A neutral grounding resistor fault protection arrangement. The fault protection arrangement may include a neutral grounding resistor, the neutral grounding resistor comprising a ground end and a non-ground end; a sense circuit, coupled to the non-ground end of the neutral grounding resistor; and a neutral grounding monitor, coupled to the non-ground end of the neutral grounding resistor, the neutral grounding monitor comprising an injection signal generator, the injection signal generator arranged to generate a frequency of 240 Hz or greater.
    Type: Application
    Filed: March 8, 2019
    Publication date: September 19, 2019
    Applicant: Littelfuse, Inc.
    Inventors: Kristophor Jensen, Kip M. Larson, Cornelis Verhey
  • Publication number: 20190288502
    Abstract: A fault protection arrangement may include a neutral grounding resistor, the neutral grounding resistor comprising a ground end and a non-ground end. The fault protection arrangement may include a neutral grounding resistance monitor assembly, coupled to the neutral grounding resistor, where the neutral grounding resistance monitor assembly includes a sense circuit, coupled to the ground end of the neutral grounding resistor; and an injection signal generator, arranged to generate a frequency of 240 Hz or greater.
    Type: Application
    Filed: March 8, 2019
    Publication date: September 19, 2019
    Applicant: Littelfuse, Inc.
    Inventors: Kristophor Jensen, Kip M. Larson, Cornelis Verhey
  • Patent number: 10395877
    Abstract: The present invention proposes a protection device which has a large rated voltage and a large rated current, which is capable of sufficiently suppressing arc generation during activation, and which is also capable of providing suitable protection against overcurrent due to short circuiting or the like of a main circuit. The protection device of the present invention includes (i) a protection element which includes a first thermal fuse and a resistor, and in which the resistor generates heat as a result of current passing through the resistor when there are abnormalities, and the first thermal fuse is activated due to this heat and interrupts the current, (ii) a PTC element and a second thermal fuse which are electrically connected in parallel to the first thermal fuse and which are electrically connected in series to each other, and (iii) a current fuse which is electrically connected in series to the first thermal fuse.
    Type: Grant
    Filed: March 4, 2015
    Date of Patent: August 27, 2019
    Assignee: Littelfuse, Inc.
    Inventors: Masaaki Iwai, Takayuki Yokota
  • Publication number: 20190261476
    Abstract: A current driver integrated circuit (IC) is coupled to control current flow through a diode. In one example, the diode is a Light Emitting Diode (LED) having an anode coupled to a supply node supplied by a battery and a cathode coupled to a drive terminal of the current driver IC. During operation the current driver IC is enabled and sinks an output current from the supply node, through the LED, through the drive terminal, and onto a ground node. As current flows through the LED, the battery is discharged. Changes in battery voltage cause an output voltage between the cathode of the LED and the ground node to change. Despite variations in output voltage, the current driver IC maintains a current level of the output current to be within five percent of a desired output current level across an output voltage range of at least 2V.
    Type: Application
    Filed: January 4, 2019
    Publication date: August 22, 2019
    Applicant: Littelfuse, Inc.
    Inventor: Bret Ross Howe
  • Publication number: 20190259556
    Abstract: A fuse including a first housing part and a second housing part that are joined together to define a cavity, a fuse element disposed within the cavity, a first terminal extending from a first end of the fuse element and out of the housing, and a second terminal extending from a second end of the fuse element and out of the housing, the housing having a vent channel extending from an outer surface of the housing to the cavity for allowing vapor to escape from the cavity.
    Type: Application
    Filed: May 4, 2019
    Publication date: August 22, 2019
    Applicant: Littelfuse, Inc.
    Inventor: Michael Schlaak
  • Publication number: 20190260281
    Abstract: In a switching converter having an inductive load, a current may flow through the body diode of a transistor even though the gate of the transistor is being controlled to keep the transistor off. Then when the other transistor of the switch leg is turned on, a reverse recovery current flows in the reverse direction through the body diode. To reduce switching losses associated with such current flows, a gate driver integrated circuit detects when current flow through the body diode rises above a threshold current. The gate driver integrated circuit then controls the transistor to turn on. Then when the other transistor of the switch leg is made to turn on, the gate driver first turns the transistor off. When the gate-to-source voltage of the turning off transistor drops below a threshold voltage, then the gate driver integrated circuit allows and controls the other transistor to turn on.
    Type: Application
    Filed: October 2, 2018
    Publication date: August 22, 2019
    Applicant: Littelfuse, Inc.
    Inventors: Anatoliy V. Tsyrganovich, Leonid A. Neyman, Md Abdus Sattar, Vladimir Tsukanov
  • Patent number: 10388482
    Abstract: Approaches herein provide a fuse assembly including a multi-part symmetrical housing. In some embodiments, the fuse assembly includes a core having a set of fusible elements extending between a first end fitting and a second end fitting, and a housing surrounding the core. The housing may include a first section having a first wall defining a first internal cavity, the first wall including a first slot and a first ridge, and a second section coupled to the first section, the second section having a second wall defining a second internal cavity. The second wall may include a second slot and a second ridge, wherein the first slot engages the second ridge and the second slot engages the first ridge. In some embodiments, the first and second sections define a set of openings for the first and second end fittings to extend therethrough.
    Type: Grant
    Filed: January 5, 2018
    Date of Patent: August 20, 2019
    Assignee: Littelfuse, Inc.
    Inventors: Nathan C. Siegwald, Dustin Kurtz
  • Patent number: 10389106
    Abstract: A cable including a power conductor configured to transmit electrical power between a first device and a second device, a first data conductor configured to transmit data between the first device and the second device, and a first protection circuit coupled to the first data conductor and associated with a first temperature sensing element, the first protection circuit configured to mitigate current flowing through the first data conductor if a temperature detected by the first temperature sensing element rises above a predefined first trip temperature, wherein the opening of the first data line indicates a fault condition to a device to which the cable is connected, whereby electrical power flowing through the power conductor is resultantly mitigated.
    Type: Grant
    Filed: March 19, 2018
    Date of Patent: August 20, 2019
    Assignee: Littelfuse, Inc.
    Inventors: Boris Golubovic, Kunghao Yu
  • Publication number: 20190252284
    Abstract: A power semiconductor device module includes, among other parts, a DMB structure. The DMB structure includes a ceramic sheet, a top metal plate that is directly bonded to the top of the ceramic, and a bottom metal plate that is directly bonded to the bottom of the ceramic. A power semiconductor device die is attached to the top metal plate. The bottom surface of the bottom metal plate has a plurality small cavities. When the bottom metal plate is attached to another metal member, a material between the plate and the member (for example, thermal grease or a PCM or solder) is forced into the cavities. This results in an improvement in thermal transfer between the plate and the member. Such cavities can alternatively, or in addition, be included on a metal surface other than a DMB, such as the bottom surface of a baseplate of the module.
    Type: Application
    Filed: April 29, 2019
    Publication date: August 15, 2019
    Applicant: Littelfuse, Inc.
    Inventor: Thomas Spann, Jr.
  • Publication number: 20190252990
    Abstract: An AC-to-DC converter circuit includes DC-to-DC converter that in turn includes a secondary side circuit. The secondary side circuit includes a secondary winding, a pair of bipolar transistor-based self-driven synchronous rectifiers, a pair of current splitting inductors, and an output capacitor. Each of the synchronous rectifiers includes a bipolar transistor and a diode whose anode is coupled to the transistor collector and whose cathode is coupled to the transistor emitter. The current splitting inductors provide the necessary base current to the bipolar transistors at the appropriate times such that the bipolar transistors operate as synchronous rectifiers.
    Type: Application
    Filed: November 30, 2015
    Publication date: August 15, 2019
    Applicant: Littelfuse, Inc.
    Inventor: Kyoung Wook Seok
  • Patent number: 10375784
    Abstract: A current driver integrated circuit (IC) is coupled to control current flow through a diode. In one example, the diode is a Light Emitting Diode (LED) having an anode coupled to a supply node supplied by a battery and a cathode coupled to a drive terminal of the current driver IC. During operation the current driver IC is enabled and sinks an output current from the supply node, through the LED, through the drive terminal, and onto a ground node. As current flows through the LED, the battery is discharged. Changes in battery voltage cause an output voltage between the cathode of the LED and the ground node to change. Despite variations in output voltage, the current driver IC maintains a current level of the output current to be within five percent of a desired output current level across an output voltage range of at least 2V.
    Type: Grant
    Filed: January 4, 2019
    Date of Patent: August 6, 2019
    Assignee: Littelfuse, Inc.
    Inventor: Bret Ross Howe
  • Patent number: 10367085
    Abstract: An IGBT includes a floating P well and a floating N+ well that extends down into the floating P well. A bottom surface of the floating P well has a waved contour with thinner portions and thicker portions. When the device is on, electrons flow laterally from an N+ emitter and through a channel region. Some electrons pass downward, but others pass laterally through the floating N+ well to one of the thinner portions of the floating P type well. The electrons then pass down from the thinner portions into the N? drift layer. Other electrons pass farther through the floating N+ well to subsequent, thinner electron injector portions of the floating P type well and then into the N? drift layer. The extra electron injection afforded by the waved floating well structure reduces VCE(SAT). The waved contour is made without adding any masking step to the IGBT manufacturing process.
    Type: Grant
    Filed: September 24, 2015
    Date of Patent: July 30, 2019
    Assignee: Littelfuse, Inc.
    Inventor: Kyoung Wook Seok
  • Publication number: 20190228940
    Abstract: Provided herein are modular fuse holders for single bolt fuses. In some approaches, a fuse holder may include a base having a lower wall and a set of sidewalls, the lower wall including a plurality of bolt openings provided therethrough. The fuse holder may further include a cover securable with the base, the cover including an upper wall and a set of outer walls, the outer walls including a plurality of cable openings, wherein the base and the cover define an interior cavity for housing a bolt assembly. In some approaches, the fuse holder may include a busbar atop the lower wall of the base, the busbar including a set of openings aligned with one or more of the bolt openings of the lower wall. In some embodiments, a side cover may extend over some of the plurality of cable openings in the outer wall of the cover.
    Type: Application
    Filed: January 23, 2018
    Publication date: July 25, 2019
    Applicant: Littelfuse, Inc.
    Inventors: Hermann Bommersheim, Patric Gross, Geoff Schwartz
  • Publication number: 20190227111
    Abstract: Embodiments herein are directed to systems and methods for single wire precision measurement of a ground termination circuit. In some embodiments, a ground check monitoring apparatus includes a voltage source connected to a single insulated ground check wire, a pilot conductor, and a ground conductor, wherein the pilot conductor has a first resistance, and the ground conductor has a second resistance. The apparatus further includes a termination device connected between the pilot conductor and the ground conductor, and a ground conductor terminal connectable to a cable pilot wire. The apparatus may further include a ground terminal connectable with a cable ground wire, wherein voltage and current measured at the ground check terminal and the ground terminal are used to determine a ground check resistance.
    Type: Application
    Filed: January 23, 2018
    Publication date: July 25, 2019
    Applicant: Littelfuse, Inc.
    Inventors: Daryl Warkentin, George Fenty, Kim Haluik
  • Patent number: 10361276
    Abstract: A trench N-channel field effect transistor has an active area and an edge area. A first pair of parallel-extending deep trenches extends parallel to a side edge of the die. A second pair of parallel-extending deep trenches extends perpendicularly to the side edge, toward the side edge, so that each trench of the second pair terminates into the inside deep trench of the first pair. An embedded field plate structure is embedded in these trenches. A plurality of floating P type well regions is disposed entirely between the second pair of deep trenches, between the active area and the inside deep trench of the first pair. Using this edge area structure, the breakdown voltage BVDSS of the overall device is increased because the breakdown voltage of the edge area is increased as compared to the same structure without the floating P type well regions.
    Type: Grant
    Filed: March 17, 2018
    Date of Patent: July 23, 2019
    Assignee: Littelfuse, Inc.
    Inventor: Kyoung Wook Seok
  • Patent number: 10361055
    Abstract: Provided herein are modular fuse holders for single bolt fuses. In some approaches, a fuse holder may include a base having a lower wall and a set of sidewalls, the lower wall including a plurality of bolt openings provided therethrough. The fuse holder may further include a cover securable with the base, the cover including an upper wall and a set of outer walls, the outer walls including a plurality of cable openings, wherein the base and the cover define an interior cavity for housing a bolt assembly. In some approaches, the fuse holder may include a busbar atop the lower wall of the base, the busbar including a set of openings aligned with one or more of the bolt openings of the lower wall. In some embodiments, a side cover may extend over some of the plurality of cable openings in the outer wall of the cover.
    Type: Grant
    Filed: January 23, 2018
    Date of Patent: July 23, 2019
    Assignee: Littelfuse, Inc.
    Inventors: Hermann Bommersheim, Patric Gross, Geoff Schwartz
  • Publication number: 20190221396
    Abstract: Approaches herein provided surface mounted devices each configured as a stand-alone component suitable for attachment to a substrate such as a printed circuit board (PCB). In some embodiments, a method includes forming a base housing, coupling an electronic component to the base housing, and forming a cover over the electronic component, wherein the cover is coupled to the base housing. The electronic component may include a fusible link/element extending between terminals, the terminals wrapped around an exterior of base housing. The device may then be coupled to the PCB, for example, by attaching the terminals to an upper surface of the PCB.
    Type: Application
    Filed: March 26, 2019
    Publication date: July 18, 2019
    Applicant: Littelfuse, Inc.
    Inventors: James Beckert, Gregory Stumpo
  • Publication number: 20190221397
    Abstract: A surface mount fuse including a fuse body having a base including a floor and a plurality of adjoining sidewalls defining an interior cavity, wherein top edges of the sidewalls define a recessed shoulder bordering the interior cavity, and a cover including a main body disposed on the recessed shoulder and enclosing the interior cavity, first and second terminals extending through opposing sidewalls of the base, the first and second terminals extending around the opposing sidewalls and the cover and disposed in abutment therewith to secure the cover to the base, and a fusible element extending through the interior cavity and connected to the first and second terminals.
    Type: Application
    Filed: March 26, 2019
    Publication date: July 18, 2019
    Applicant: Littelfuse, Inc.
    Inventors: Conrado de Leon, Albert Enriquez