Patents Assigned to Allegro Microsystems Inc.
  • Publication number: 20130320941
    Abstract: A magnetic field sensor has internal power supply generating circuits to generate a higher operating voltage for a magnetic field sensing element, resulting in a magnetic field sensor with improved sensitivity to magnetic fields.
    Type: Application
    Filed: May 31, 2012
    Publication date: December 5, 2013
    Applicant: ALLEGRO MICROSYSTEMS, INC.
    Inventors: Mauricio Contaldo, Gergory Szczeszynski, Gerardo Monreal
  • Publication number: 20130320970
    Abstract: Presented herein is a magnetic field sensor architecture that uses outputs of a peak detector and threshold detector operating in parallel to detect magnetic anomalies that may be associated with the target being sensed, e.g., a rotational ferromagnetic object such as a toothed gear, and use such detection to prevent sensor malfunction. The sensor includes an edge detection circuit and an error detection circuit. In one embodiment, the edge detection circuit includes circuits to detect edges (or transitions) of the threshold and peak detector output signals and the error detection circuit includes circuits, responsive to the edge detection circuit, to indicate an error when a “missed transition” occurs or a peak-to-peak value of an input signal as detected by the peak detector for a current cycle differs from an expected peak-to-peak value by a predetermined amount.
    Type: Application
    Filed: May 31, 2012
    Publication date: December 5, 2013
    Applicant: Allegro Microsystems, Inc.
    Inventors: Andrea Foletto, Michael Morris, Mathew Drouin, Devon Fernandez, Andreas P. Friedrich, P. Karl Scheller
  • Publication number: 20130314836
    Abstract: Circuits and methods for overcurrent fault detection using a debounce timer to qualify the presence of an overcurrent fault based on an overcurrent signal being asserted for at least a predetermined time interval. The debounce timer may be used in conjunction with state-qualified fault sensing and/or blank-time-qualified fault sensing.
    Type: Application
    Filed: May 24, 2012
    Publication date: November 28, 2013
    Applicant: ALLEGRO MICROSYSTEMS, INC.
    Inventor: Robert Douglas Christie
  • Publication number: 20130300406
    Abstract: Methods and apparatus for a magnetic field sensor including a die, a coil proximate the die to generate a magnetic field, and a magnetic field sensing element having to detect changes in the magnetic field generated by the coil in response to a ferromagnetic target.
    Type: Application
    Filed: May 10, 2012
    Publication date: November 14, 2013
    Applicant: ALLEGRO MICROSYSTEMS INC.
    Inventors: Gary T. Pepka, William P. Taylor
  • Publication number: 20130293220
    Abstract: Methods and apparatus for a magnetic sensor including an elliptical magnet to generate substantially circular concentric zones of similar flux density in a plane over and parallel to a surface of the magnet. The sensor can include a sensing element disposed a selected distance from the magnet and a substrate containing circuitry to process a signal from the sensing element to provide a sensor output.
    Type: Application
    Filed: May 1, 2012
    Publication date: November 7, 2013
    Applicant: ALLEGRO MICROSYSTEMS INC.
    Inventors: Ryan Metivier, William P. Taylor
  • Publication number: 20130264667
    Abstract: Magnetic field sensors and associated methods of manufacturing the magnetic field sensors include molded structures to encapsulate a magnetic field sensing element and an associated die attach pad of a lead frame and to also encapsulate or form a magnet or a flux concentrator.
    Type: Application
    Filed: March 15, 2013
    Publication date: October 10, 2013
    Applicant: Allegro Microsystems, Inc.
    Inventors: Virgil Ararao, Nirmal Sharma, Raymond W. Engel, Jay Gagnon, John B. Sauber, William P. Taylor, Elsa Kam-Lum
  • Publication number: 20130267043
    Abstract: Magnetic field sensors and associated methods of manufacturing the magnetic field sensors include molded structures to encapsulate a magnetic field sensing element and an associated die attach pad of a lead frame and to also encapsulate or form a magnet or a flux concentrator.
    Type: Application
    Filed: March 15, 2013
    Publication date: October 10, 2013
    Applicant: Allegro Microsystems, Inc.
    Inventors: Virgil Ararao, Nirmal Sharma, Raymond W. Engel, Jay Gagnon, John B. Sauber, William P. Taylor, Elsa Kam-Lum
  • Publication number: 20130265041
    Abstract: A sensor with multiple magnetic field sensing elements for use in current sensing and other applications is presented. In one configuration, the sensor can obtain differential and absolute current measurements of current in current-carrying conductors. When employed in a ground fault interrupter (GFI) application, a first magnetic field sensing element can be used to measure the absolute current flowing in the phase conductor (phase current), a second magnetic field sensing element can be used to measure the absolute current flowing in the neutral conductor (neutral current) and a difference between the phase and neutral currents can be measured by a third magnetic field sensing element or determined from measurements of the first and second magnetic field sensing elements. In another configuration, the sensor can obtain a measure of the difference between currents and/or the sum of currents in current-carrying conductors.
    Type: Application
    Filed: April 4, 2012
    Publication date: October 10, 2013
    Applicant: Allegro Microsystems, Inc.
    Inventors: Andreas P. Friedrich, Andrea Foletto, P. Karl Scheller, William P. Taylor, Michael C. Doogue
  • Publication number: 20130265036
    Abstract: A sensor with multiple magnetic field sensing elements for use in current sensing and other applications is presented. The sensor includes an arrangement of two or more magnetic field sensing elements to sense magnetic field associated with a target. The sensor further includes circuitry to generate a sensor output signal based on sensing of at least one of the magnetic field sensing elements of the arrangement. Also included is a programmable misalignment adjustment block to control the circuitry to generate the output signal with compensation for misalignment between the sensor and the target. The programmable misalignment adjustment block can be programmed to select measurement of one of the two or more magnetic field sensing elements, or alternatively, a mathematical combination of measurements of the two or more magnetic field sensing elements, for generating the sensor output signal when a test of the sensor indicates a misalignment.
    Type: Application
    Filed: April 4, 2012
    Publication date: October 10, 2013
    Applicant: Allegro Microsystems, Inc.
    Inventors: Andreas P. Friedrich, Andrea Foletto, P. Karl Scheller, William P. Taylor, Michael C. Doogue
  • Publication number: 20130265037
    Abstract: An angle sensor to provide sensor-to-magnet misalignment detection and correction capability in rotation angle measurement applications is presented. The angle sensor has magnetic field sensing elements to sense magnetic field associated with a rotating magnet. The angle sensor includes circuitry to generate signals based on the sensing by the sensing elements. The signals provide information that can be combined according to an error function to provide misalignment detection. The angle sensor can be used with or can be incorporated in an angle measurement device that employs a processing unit to produce a rotation angle value. In one embodiment, the processing unit is configured to implement the error function and correct the angle value for detected misalignment. In another embodiment, the error function is performed by a programming device and detected misalignment is corrected through mechanical adjustment of sensor-to-magnet position.
    Type: Application
    Filed: April 4, 2012
    Publication date: October 10, 2013
    Applicant: Allegro Microsystems, Inc.
    Inventors: Andreas P. Friedrich, Andrea Foletto, P. Karl Scheller, William P. Taylor, Michael C. Doogue
  • Publication number: 20130249544
    Abstract: A magnetic field sensor includes a lead frame, a semiconductor die supporting a magnetic field sensing element, a non-conductive mold material enclosing the die and a portion of the lead frame, a ferromagnetic mold material secured to the non-conductive mold material and a securing mechanism to securely engage the mold materials. The ferromagnetic mold material may comprise a soft ferromagnetic material to form a concentrator or a hard ferromagnetic material to form a bias magnet. The ferromagnetic mold material may be tapered and includes a non-contiguous central region, as may be an aperture or may contain the non-conductive mold material or an overmold material. Further embodiments include die up, lead on chip, and flip-chip arrangements, wafer level techniques to form the concentrator or bias magnet, integrated components, such as capacitors, on the lead frame, and a bias magnet with one or more channels to facilitate overmolding.
    Type: Application
    Filed: March 20, 2012
    Publication date: September 26, 2013
    Applicant: ALLEGRO MICROSYSTEMS, INC.
    Inventors: Ravi Vig, William P. Taylor, Andreas P. Friedrich, Paul David, Marie-Adelaide Lo, Eric Burdette, Eric Shoemaker, Michael C. Doogue
  • Publication number: 20130249027
    Abstract: A magnetic field sensor includes a lead frame having a plurality of leads, at least two of which have a connection portion and a die attach portion. A semiconductor die is attached to the die attach portion of the at least two leads. The sensor further includes at least one wire bond coupled between the die and a first surface of the lead frame. The die is attached to a second, opposing surface of the lead frame in a lead on chip configuration. In some embodiments, at least one passive component is attached to the die attach portion of at least two leads.
    Type: Application
    Filed: March 7, 2013
    Publication date: September 26, 2013
    Applicant: ALLEGRO MICROSYSTEMS, INC.
    Inventors: William P. Taylor, Paul David, Ravi Vig
  • Publication number: 20130242447
    Abstract: An integrated circuit includes circuitry to sense the occurrence of a break in a ground connection and/or supply connection and to indicate same to an exterior environment. In at least one implementation, the break may be indicated by providing a signal on an output terminal of the device that is not associated with a normal output of the device.
    Type: Application
    Filed: March 19, 2012
    Publication date: September 19, 2013
    Applicant: Allegro Microsystems, Inc.
    Inventors: Franco Noel Martin Pirchio, Cory Voisine, Hernan D. Romero, Gerardo Monreal
  • Publication number: 20130238278
    Abstract: A magnetic field sensor uses an angle sensor to measure and angle of rotation of a target object to which a magnet is attached. The angle sensor in combination with electronics can generate an angle sensor output signal related to a direction of a magnetic field of the magnet. The angle sensor output signal can be compared to thresholds to generate a magnetic field sensor output signal the same as a known true power on state (TPOS) sensor output signal. A corresponding method is also described.
    Type: Application
    Filed: March 6, 2012
    Publication date: September 12, 2013
    Applicant: ALLEGRO MICROSYSTEMS, INC.
    Inventors: Eric Shoemaker, Michael C. Doogue, Andreas P. Friedrich, Andrea Foletto
  • Publication number: 20130214774
    Abstract: A magnetic field sensor includes a reference-field-sensing circuit channel that allows a self-test or a self-calibration of the circuitry of the magnetic field sensor. The self-test or the self calibration can have at least two different bandwidths that provide a respective at least two different rates of self-test or self-calibration.
    Type: Application
    Filed: February 16, 2012
    Publication date: August 22, 2013
    Applicant: ALLEGRO MICROSYSTEMS, INC.
    Inventors: Juan Manuel Cesaretti, Hernan D. Romero
  • Publication number: 20130181304
    Abstract: Methods and apparatus to provide an integrated circuit package having a conductive leadframe, a non-conductive die paddle mechanically coupled to the leadframe, and a die disposed on the die paddle and electrically connected to the leadframe. With this arrangement, eddy currents are reduced near the magnetic field transducer to reduce interference with magnetic fields.
    Type: Application
    Filed: January 16, 2012
    Publication date: July 18, 2013
    Applicant: ALLEGRO MICROSYSTEMS, INC.
    Inventors: Shaun D. Milano, Michael C. Doogue, William P. Taylor
  • Publication number: 20130177040
    Abstract: A magnetic field sensor includes a true power on state (TPOS) detector for which a measured threshold value is stored prior to power down and recalled upon power up. A corresponding method is associated with the magnetic field sensor.
    Type: Application
    Filed: January 6, 2012
    Publication date: July 11, 2013
    Applicant: ALLEGRO MICROSYSTEMS, INC.
    Inventors: Andrea Foletto, Peter Cisar, Eric Shoemaker
  • Publication number: 20130179115
    Abstract: A system and an associated method provide an ability to sense, with a magnetic field sensor, a position of a plurality of gears (and neutral) selected by a gear shift lever of a vehicle. In some embodiments, the system and method use a ferromagnetic target having features, positions of which can be sensed by the magnetic field sensor. In other embodiments, the system and method use a magnet having features and characteristics that can be sensed by the magnetic field sensor.
    Type: Application
    Filed: May 31, 2012
    Publication date: July 11, 2013
    Applicant: ALLEGRO MICROSYSTEMS, INC.
    Inventors: Andreas P. Friedrich, Andrea Foletto, Cedric Gillet
  • Publication number: 20130176012
    Abstract: Methods and apparatus for an integrated circuit that includes a supply voltage transient detection module to activate a hold signal that causes the output to remain in its present state. In one embodiment, the output remains in that state until the supply voltage returns to a normal operating range and the hold signal transitions to an inactive state.
    Type: Application
    Filed: January 5, 2012
    Publication date: July 11, 2013
    Applicant: ALLEGRO MICROSYSTEMS, INC.
    Inventors: Jeff Eagen, Devon Fernandez, P. Karl Scheller
  • Publication number: 20130162152
    Abstract: In one aspect, a circuit includes a plurality of comparators. Each comparator is configured to receive a first input from a corresponding load of a plurality of loads and to receive a second input as a regulation voltage. The circuit also includes an amplifier configured to receive signals provided by the plurality of comparators, a pulse-width modulation (PWM) circuit configured to receive a control signal from the amplifier and to provide a signal to a primary switch to control voltage provided to the loads and an output switch sequencer coupled to each of the comparators and configured to provide control signals to control switches coupled to the primary switch enabling one control switch to be active at a time. Each control switch provides a voltage increase to a respective load of the plurality of loads if enabled.
    Type: Application
    Filed: December 22, 2011
    Publication date: June 27, 2013
    Applicant: Allegro Microsystems, Inc.
    Inventors: Nai-Chi Lee, Gregory Szczeszynski, Vijay Mangtani