Patents Assigned to Allegro Microsystems Inc.
  • Patent number: 7777607
    Abstract: A material stack has an electrical resistance generally the same in the presence of a magnetic field and in the presence of no magnetic field. The electrical resistance of the material stack has a temperature coefficient generally the same as a magnetoresistance element.
    Type: Grant
    Filed: October 12, 2004
    Date of Patent: August 17, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: William P. Taylor, Michael C. Doogue
  • Patent number: 7772838
    Abstract: Apparatus for detecting vibration of an object adapted to rotate includes one or more vibration processors selected from: a direction-change processor adapted to detect changes in a direction of rotation of the object, a direction-agreement processor adapted to identify a direction of rotation of the object in at least two channels and identify an agreement or disagreement in direction of rotation identified by the at least two channels, a phase-overlap processor adapted to identify overlapping signal regions in signals associated with the rotation of the object, and a running mode processor adapted to identify an unresponsive output signal from at least one of the at least two channels.
    Type: Grant
    Filed: December 18, 2008
    Date of Patent: August 10, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: James M. Bailey, Michael C. Doogue, Jay M. Towne
  • Patent number: 7768083
    Abstract: An integrated circuit can have a first substrate supporting a magnetic field sensing element and a second substrate supporting another magnetic field sensing element. The first and second substrates can be arranged in a variety of configurations. Another integrated circuit can have a first magnetic field sensing element and second different magnetic field sensing element disposed on surfaces thereof.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: August 3, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: Michael C. Doogue, William P. Taylor, Vijay Mangtani
  • Publication number: 20100181997
    Abstract: A sensor includes a signal generation module including a magnetic sensor to provide position information for generating first and second waveforms corresponding to the position information. An analog signal processing module provides an algebraic manipulation of a subset of the first waveform, the second waveform, a first inverted waveform, and a second inverted waveform, to generate a linear output signal.
    Type: Application
    Filed: March 29, 2010
    Publication date: July 22, 2010
    Applicant: Allegro Microsystems, Inc.
    Inventors: Monica J. Thomas, Michael C. Doogue, Hooman Bustani
  • Patent number: 7746056
    Abstract: An electronic circuit includes a substrate having a surface and a device supported by the surface of the substrate. The electronic circuit also includes a magnetic field transducer disposed over the surface of the substrate and an insulating layer disposed between the substrate and the magnetic field transducer. The electronic circuit also includes a conductor disposed over the magnetic field transducer. The conductor is configured to carry an electrical current to generate a first magnetic field. The electronic circuit is responsive to the first magnetic field.
    Type: Grant
    Filed: January 22, 2009
    Date of Patent: June 29, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: Jason Stauth, Richard Dickinson, Glenn Forrest, Ravi Vig
  • Patent number: 7747146
    Abstract: In one aspect, a control circuit to control a speed of a motor includes a control logic circuit connected to a multifunction port. The control logic circuit is configured to receive a control signal provided at the multifunction port and to provide response signals based on the control signal to place the motor in at least two of a sleep mode, a brake mode and a pulse-width modulation (PWM) mode. The motor control circuit also includes an H-bridge circuit configured to control the motor based on the response signals.
    Type: Grant
    Filed: August 8, 2007
    Date of Patent: June 29, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: Shaun D. Milano, Alejandro G. Milesi, Nevenka Kozomora
  • Patent number: 7715219
    Abstract: A non-volatile one time programmable memory cell couples in series a two terminal fuse and a three terminal antifuse. The non-volatile one time programmable memory cell includes a memory cell write enable node and a memory cell output node. The non-volatile one time programmable memory cell includes fuse having a first node and a second node, and an antifuse having a trigger node, a first node, and a second node. The trigger node is coupled to the memory cell write enable node. The first node of the antifuse and the second node of the fuse are coupled to the memory cell output node. First and second voltages appearing at the memory cell output node are indicative of first and second binary states of the memory cell. A plurality of such memory cells can be included in a non-volatile programmable memory array. A non-volatile programmable memory cell capable of re-programming is also included.
    Type: Grant
    Filed: June 30, 2008
    Date of Patent: May 11, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventor: Gerardo Monreal
  • Patent number: 7714570
    Abstract: Methods and apparatus for a sensor include a signal generation module including a first magnetic sensor to generate a first waveform in the form of a sine wave and a second magnetic sensor to generate a second waveform in the form of a cosine wave, the first and second waveforms containing angular position information of a magnet in relation to the first and second magnetic sensors, and an analog signal processing module for providing an algebraic manipulation of the first waveform and the second waveform to generate a linear position output voltage signal.
    Type: Grant
    Filed: June 21, 2006
    Date of Patent: May 11, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: Monica J. Thomas, Michael C. Doogue, Hooman Bustani
  • Patent number: 7709754
    Abstract: An integrated circuit current sensor includes a lead frame having at least two leads coupled to provide a current conductor portion, and substrate having a first surface in which is disposed one or more magnetic field transducers, with the first surface being proximate the current conductor portion and a second surface distal from the current conductor portion. In one particular embodiment, the substrate is disposed having the first surface of the substrate above the current conductor portion and the second surface of the substrate above the first surface. In this particular embodiment, the substrate is oriented upside-down in the integrated circuit relative to a conventional orientation. With this arrangement, a current sensor is provided for which the one or more magnetic field transducers are very close to the current conductor portion, resulting in a current sensor having improved sensitivity.
    Type: Grant
    Filed: August 26, 2003
    Date of Patent: May 4, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: Michael Doogue, Richard Dickinson, Jay Gagnon
  • Patent number: 7694200
    Abstract: An integrated circuit and a method of built-in self test in the integrated circuit employ an offset control node and offset capabilities with the integrated circuit in order to communicate and distribute a built-in self-test signal. The built-in self-test signal can emulate signals internal to the integrated circuit during normal operation, and/or the built-in self-test signal can have other signal characteristics representative of signals other than those signals internal to the integrated circuit during normal operation.
    Type: Grant
    Filed: July 18, 2007
    Date of Patent: April 6, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: Glenn A. Forrest, Washington Lamar
  • Patent number: 7687882
    Abstract: An integrated circuit comprises a plurality of layers including a first substrate with an on chip capacitor and a second substrate. In one embodiment, the second substrate has an on chip capacitor. The first and/or second substrate can include a sensor element, such as a magnetic sensor element.
    Type: Grant
    Filed: October 31, 2006
    Date of Patent: March 30, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: William P. Taylor, Ravi Vig
  • Publication number: 20100072922
    Abstract: An electronic circuit includes circuit portions for identifying a largest voltage drop through one of a plurality of series connected diode strings and for controlling a boost switching regulator according to the largest voltage drop. The electronic circuit can sense an open circuit series connected diode string, which would otherwise have the largest voltage drop, and can disconnect that open circuit series connected diode string from control of the boost switching regulator. Another electronic circuit includes a current limiting circuit coupled to or within a boost switching regulator and configured to operate with a diode load. Another electronic circuit includes a pulse width modulation circuit configured to dim a series connected string of light emitting diodes.
    Type: Application
    Filed: December 2, 2009
    Publication date: March 25, 2010
    Applicant: Allegro Microsystems, Inc.
    Inventors: Gregory Szczeszynski, Shashank Wekhande, Vijay Mangtani
  • Patent number: 7676914
    Abstract: In an exemplary embodiment, a method for a magnetic sensor includes forming a first conductive layer over a substrate containing circuitry, forming a dielectric layer over the first conductive layer, forming a second conductive layer over the dielectric layer such that the first conductive layer, the dielectric layer, and the second conductive layer form a first capacitor, and providing first and second terminals, wherein the first terminal is coupled to the first conductive layer and the second terminal is coupled to the second conductive layer.
    Type: Grant
    Filed: October 23, 2007
    Date of Patent: March 16, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventor: William P. Taylor
  • Patent number: 7675245
    Abstract: An electronic circuit includes circuit portions for identifying a largest voltage drop through one of a plurality of series connected diode strings and for controlling a boost switching regulator according to the largest voltage drop. The electronic circuit can sense an open circuit series connected diode string, which would otherwise have the largest voltage drop, and can disconnect that open circuit series connected diode string from control of the boost switching regulator. Another electronic circuit includes a current limiting circuit coupled to or within a boost switching regulator and configured to operate with a diode load. Another electronic circuit includes a pulse width modulation circuit configured to dim a series connected string of light emitting diodes.
    Type: Grant
    Filed: January 4, 2007
    Date of Patent: March 9, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: Gregory Szczeszynski, Shashank Wekhande, Vijay Mangtani
  • Publication number: 20100013467
    Abstract: A rotation sensor includes a detecting portion, a rotational state determining portion and a pulse generating portion. The detecting portion detects a rotation of a rotational member and outputs a detection signal. The rotational state determining portion determines a rotational state of the rotational member on the basis of the detection signal in a predetermined period. The pulse generating portion generates and outputs a first pulse and a second pulse, of which waveforms differ from each other, in response to a rotational direction of the rotational member after the predetermined period. The pulse generating portion further generates and outputs a third pulse regardless of the rotational state of the rotational member in the predetermined period.
    Type: Application
    Filed: July 17, 2009
    Publication date: January 21, 2010
    Applicants: AISIN SEIKI KABUSHIKI KAISHA, ALLEGRO MICROSYSTEMS, INC.
    Inventors: Takashi HARA, Hidenobu MURAMATSU, Glenn A. FORREST, Hitoshi YABUSAKI, Naota NAKAYAMA
  • Patent number: 7649325
    Abstract: A circuit includes a capacitive element for coupling across a load element to be energized by a DC signal, a first sense element to monitor an instantaneous sum of currents through the load element and the capacitive element, a switching element to control current through the first sense element, a second sense element coupled to the switching element to sense current through the switching element, an energy storage element coupled to the switching element, a unidirectional current flow element allowing current flow to the load element, and a converter circuit to control the switching element, wherein the converter circuit regulates to the current level monitored across the first sense element, and wherein a converter regulation loop includes a dominant pole to average the current sensed through the first sense element.
    Type: Grant
    Filed: April 3, 2006
    Date of Patent: January 19, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: James A. McIntosh, Aldo Togneri, Robert D. Christie
  • Patent number: 7646616
    Abstract: A capacitor charging circuit is provided with a primary side output voltage sensing circuit for generating a control signal indicative of whether the output voltage has reached a desired level. The control signal is unaffected by voltage spikes occurring when the main switch is turned off. In one embodiment, the circuit filters the primary side voltage for comparison to a reference voltage in order to provide the control signal. In another embodiment, an AND gate provides the control signal indicating that the output voltage has reached the desired level only in response to the primary side voltage being greater than a reference voltage and the secondary current being discontinuous. In a further embodiment, an AND gate provides the control signal indicating that the output voltage has reached the desired levels only in response to a predetermined delay occurring after the primary side voltage becomes greater than a reference voltage and the secondary current being discontinuous.
    Type: Grant
    Filed: May 9, 2005
    Date of Patent: January 12, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: Shashank S. Wekhande, Vijay R. Mangtani, Sihua Wen
  • Patent number: 7633115
    Abstract: Semiconductor structures are adapted to form an electrically erasable programmable read only memory (EEPROM) cell having a long retention life, and/or a reduced programming voltage, and/or a reduced semiconductor real estate, and/or a reduced number of semiconductor fabrication steps.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: December 15, 2009
    Assignee: Allegro Microsystems, Inc.
    Inventor: Yigong Wang
  • Patent number: 7622914
    Abstract: Apparatus for detecting vibration of an object adapted to rotate includes one or more vibration processors selected from: a direction-change processor adapted to detect changes in a direction of rotation of the object, a direction-agreement processor adapted to identify a direction of rotation of the object in at least two channels and identify an agreement or disagreement in direction of rotation identified by the at least two channels, a phase-overlap processor adapted to identify overlapping signal regions in signals associated with the rotation of the object, and a running mode processor adapted to identify an unresponsive output signal from at least one of the at least two channels.
    Type: Grant
    Filed: December 18, 2008
    Date of Patent: November 24, 2009
    Assignee: Allegro Microsystems, Inc.
    Inventors: James M. Bailey, Michael C. Doogue, Jay M. Towne
  • Patent number: 7619406
    Abstract: Apparatus and methods for detecting passing magnetic articles using a first, True Power On State (TPOS) detector during a first time interval and transitioning to a second, running mode detector after the first time interval, when the output of the second detector is accurate. A phase comparator is responsive to the output signal of the first and second detectors and provides a control signal indicative of a change in the phase relationship between the two output signals. An output switch controlled by the phase comparator provides, as the detector output signal, the first detector output signal during the first time interval and the second detector output signal thereafter.
    Type: Grant
    Filed: March 3, 2008
    Date of Patent: November 17, 2009
    Assignee: Allegro Microsystems, Inc.
    Inventors: Cory Voisine, Devon Fernandez, Karl Scheller, Ravi Vig, Kirsten Doogue