Patents Assigned to Allegro Microsystems, LLC
  • Publication number: 20160252590
    Abstract: A magnetic field sensor includes a circular vertical Hall (CVH) sensing element comprising a plurality of vertical Hall elements, each one of the plurality of vertical hall elements comprising respective first and second current receiving contacts. The magnetic field sensor additionally includes a sequence switches circuit coupled to the plurality of vertical Hall elements. The magnetic field sensor also includes a first current source sequentially coupled by the sequence switches circuit to the first current receiving contact of sequentially selected ones of the plurality of vertical Hall elements. The magnetic field sensor further includes a second current source sequentially coupled by the sequence switches circuit to the second current receiving contact of the sequentially selected ones of the plurality of vertical Hall elements. The first and second current sources can swap couplings in half-period intervals for each of a plurality of coupling arrangements. A corresponding method is also described.
    Type: Application
    Filed: February 27, 2015
    Publication date: September 1, 2016
    Applicant: Allegro Microsystems, LLC
    Inventor: Aurelian Diaconu
  • Patent number: 9425785
    Abstract: A driver circuit for driving a switching transistor having a control terminal responsive to a switching control signal includes a plurality of driver stages, each having a control input responsive to a respective driver control signal and an output coupled to the output of the other driver stages and to the control terminal of the switching transistor. At least one of the driver control signals has an on time that is delayed with respect to the other driver control signals. In an embodiment, at least two driver stages are on during a slew time interval.
    Type: Grant
    Filed: July 14, 2015
    Date of Patent: August 23, 2016
    Assignee: Allegro Microsystems, LLC
    Inventor: Joshua Wibben
  • Publication number: 20160238462
    Abstract: In one aspect, a temperature detection circuit includes a first circuit configured to provide a first signal and a comparator circuit configured to provide a warning signal in response to the first signal if a temperature reaches a temperature value. The first signal enables determination of a parameter of a magnetic sensor.
    Type: Application
    Filed: February 12, 2015
    Publication date: August 18, 2016
    Applicant: ALLEGRO MICROSYSTEMS, LLC
    Inventors: Benjamin Geiger, Devon Fernandez
  • Publication number: 20160238671
    Abstract: In an embodiment, a circuit is configured to produce a magnetic field signal having a frequency spectrum. The circuit may also produce a temperature signal. A modulation circuit may modulate the temperature signal with a frequency outside the frequency spectrum of the magnetic field signal. The modulated signal and the magnetic field signal may be combined to produce a combined signal. A separation circuit may be configured to separate component signals from the combined signal. The separation circuit may include a first filter, which, when applied to the combined signal, produces a filtered signal; a modulation circuit configured to shift the data representing the temperature signal to a baseband frequency; and a second filter configured to separate the data representing the temperature signal from the combined signal.
    Type: Application
    Filed: April 26, 2016
    Publication date: August 18, 2016
    Applicant: Allegro Microsystems, LLC
    Inventors: Mathew Drouin, Devon Fernandez, William P. Taylor
  • Patent number: 9417295
    Abstract: A magnetic field sensor has a circular vertical Hall (CVH) sensing element with a plurality of vertical Hall elements disposed over a common implant region in a substrate. The plurality of vertical Hall elements is disposed in an x-y plane. The magnetic field sensor is responsive to a magnetic field generated by a multi-pole magnet having a plurality of north poles and also a plurality of south poles arranged in a plane parallel to the x-y plane, and, in some embodiments, arranged in the x-y plane. A corresponding method is also described.
    Type: Grant
    Filed: December 21, 2012
    Date of Patent: August 16, 2016
    Assignee: Allegro MicroSystems, LLC
    Inventors: Andreas P. Friedrich, Andrea Foletto
  • Publication number: 20160231393
    Abstract: A magnetic field sensor includes a comparator detector for which a measured threshold value is stored prior to power down and recalled upon power up for use by the comparator detector. A corresponding method is associated with the magnetic field sensor.
    Type: Application
    Filed: April 19, 2016
    Publication date: August 11, 2016
    Applicant: Allegro Microsystems, LLC
    Inventors: Devon Fernandez, Haeyoung Choi
  • Publication number: 20160233670
    Abstract: In an embodiment, an electronic device comprises a shared electrical over-stress (EOS) protection circuit. The shared EOS protection circuit may be coupled between a power input terminal and ground terminal to provide an EOS current path from the power input terminal to the ground terminal, and coupled between the output terminal and the ground terminal to provide an EOS current path from the output terminal to the ground terminal. The electronic device may also include a power interruption mitigation circuit to provide power to the electronic device during interruptions or fluctuations in external power.
    Type: Application
    Filed: February 11, 2015
    Publication date: August 11, 2016
    Applicant: Allegro MicroSystems, LLC
    Inventors: Maxim Klebanov, Washington Lamar
  • Publication number: 20160233767
    Abstract: A controller for a Buck-Boost converter includes a feedback control circuit responsive to the converter output and configured to generate a control signal for the Buck switch and a feed forward control circuit responsive to the input voltage and configured to generate a control signal for the Boost switch. The feed forward circuit is decoupled from the converter output and may be programmable to select a predetermined output voltage.
    Type: Application
    Filed: February 5, 2015
    Publication date: August 11, 2016
    Applicant: Allegro Microsystems, LLC
    Inventors: Xiaowu Sun, Bassem Alnahas
  • Patent number: 9411023
    Abstract: A magnetic field sensor includes a circular vertical Hall (CVH) sensing element and at least one planar Hall element. The CVH sensing element has contacts arranged over a common implant region in a substrate. In some embodiments, the at least one planar Hall element is formed as a circular planar Hall (CPH) sensing element also having contacts disposed over the common implant region. A CPH sensing element and a method of fabricating the CPH sensing element are separately described.
    Type: Grant
    Filed: November 21, 2014
    Date of Patent: August 9, 2016
    Assignee: ALLEGRO MICROSYSTEMS, LLC
    Inventors: Andreas P. Friedrich, Andrea Foletto, Gary T. Pepka
  • Patent number: 9411025
    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 and a separately formed ferromagnetic element, such as a magnet, is disposed adjacent to the lead frame.
    Type: Grant
    Filed: April 26, 2013
    Date of Patent: August 9, 2016
    Assignee: Allegro Microsystems, LLC
    Inventors: Paul David, Ravi Vig, William P. Taylor, Andreas P. Friedrich
  • Patent number: 9400164
    Abstract: A magnetic field sensor provides an angle error value to correct errors of the magnetic field sensor. The angle error value is a function of temperature and magnetic field strength and is used to correct a measured magnetic field angle. Associated methods are also described.
    Type: Grant
    Filed: July 22, 2013
    Date of Patent: July 26, 2016
    Assignee: Allegro Microsystems, LLC
    Inventors: Steven Daubert, Richard Vreeland
  • Publication number: 20160209476
    Abstract: Apparatuses, systems, and methods that provide a delayed output signal with reduced sampling error are described. Embodiments include a clock circuit that generates a sample clock signal having a predetermined sample clock period. A sampling circuit may generate samples of a received signal during each sample clock period. An interpolation circuit may estimate a value of the received signal at times between the samples of the received signal based on at least a first sample and a second sample of the received signal. The interpolation circuit may estimate a time that the received signal crosses a threshold, and determine a time delta between the first sample and the estimated time that the received signal crosses the threshold. A delay circuit to generate a time delay substantially equal to the time delta is also included. An output signal changes state after the generated time delay.
    Type: Application
    Filed: January 19, 2015
    Publication date: July 21, 2016
    Applicant: Allegro MicroSystems, LLC
    Inventors: Christian Feucht, Thomas J. Kovalcik
  • Publication number: 20160208763
    Abstract: A magnetic field sensor for detecting motion of an object includes threshold generation circuitry and processing. Magnetic field sensing elements are configured to generate a magnetic field signal in response to a magnetic field associated with the object. A motion detector responsive to the magnetic field signal and to a threshold signal is configured to generate a detector output signal having edges occurring in response to a comparison of the magnetic field signal and the threshold signal. A speed detector responsive to the detector output signal generates a speed signal indicative of a speed of motion of the object. A threshold generator responsive to the speed signal generates the threshold signal having a level that varies in response to the speed signal.
    Type: Application
    Filed: January 20, 2015
    Publication date: July 21, 2016
    Applicant: ALLEGRO MICROSYSTEMS, LLC
    Inventors: Devon Fernandez, Mathew Drouin
  • Publication number: 20160209239
    Abstract: In an embodiment, a magnetic field sensor comprises a substrate and a first magnetoresistive element supported by the substrate. The magnetic field sensor also includes a second magnetoresistive element supported by the substrate and coupled in series with the first magnetoresistive element to form a voltage node between the first and second magnetoresistive elements, and at which an output voltage is provided that changes in response to an external magnetic field. The magnetic field sensor also includes a magnetic source that produces a local magnetic field having a strength sufficient to bias the first magnetoresistive element to a resistive value that is substantially resistant to changing in response to the external magnetic field. In embodiments, additional magnetoresistive elements are included to form an H-bridge circuit.
    Type: Application
    Filed: March 25, 2016
    Publication date: July 21, 2016
    Applicant: Allegro MicroSystems, LLC
    Inventors: Jeffrey Eagen, Paul A. David
  • Patent number: 9395391
    Abstract: A magnetic field sensor includes a comparator detector for which a measured threshold value is stored prior to power down and recalled upon power up for use by the comparator detector. A corresponding method is associated with the magnetic field sensor.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: July 19, 2016
    Assignee: Allegro Microsystems, LLC
    Inventors: Devon Fernandez, Haeyoung Choi
  • Publication number: 20160200245
    Abstract: An integrated magnetic field sensor includes a magnetic field sensing circuit and a power driving circuit disposed upon or within a common substrate. A method of powering on and off a load uses the above integrated magnetic field sensor.
    Type: Application
    Filed: January 12, 2016
    Publication date: July 14, 2016
    Applicant: Allegro Microsystems, LLC
    Inventors: Manuel Rivas, Gerardo A. Monreal, Christine M. Graham, Eric G. Shoemaker
  • Patent number: 9389060
    Abstract: A magnetic field sensor can include a plurality of magnetic field sensing elements; an angle processing circuit to generate an uncorrected x-y angle value representative of an angle of a magnetic field in an x-y plane, the uncorrected x-y angle value comprising a first angle error component; an angle error correction module to generate an x-y angle error value indicative of an error in the uncorrected x-y angle value, wherein the angle error correction module uses a sinusoidal error relationship, a sine look up table, and a coefficient table memory to determine the x-y angle error value; and a combining module to combine the uncorrected x-y angle value with the x-y angle error value. A similar method is used.
    Type: Grant
    Filed: February 13, 2013
    Date of Patent: July 12, 2016
    Assignee: Allegro Microsystems, LLC
    Inventors: Hernan D. Romero, Ricardo Scheinkerman, Gerardo A. Monreal
  • Patent number: 9383425
    Abstract: Methods and apparatus for an integrated circuit having a magnetic sensing element, a fault detection module including circuitry to detect a fault condition and to self-test operation of the circuitry to detect the fault. The integrated circuit includes a fault pin to indicate the fault condition.
    Type: Grant
    Filed: December 28, 2012
    Date of Patent: July 5, 2016
    Assignee: Allegro Microsystems, LLC
    Inventors: Shaun D. Milano, Thomas Kerdraon, Georges El Bacha, Michael Gaboury, Michael C. Doogue
  • Publication number: 20160190433
    Abstract: In one aspect, a vertical Hall effect sensor includes a semiconductor wafer having a first conductivity type and a plurality of semiconductive electrodes disposed on the semiconductor wafer. The plurality of semiconductive electrodes have the first conductivity type and include a source electrode, a first sensing electrode and a second sensing electrode, arranged such that the source electrode is between the first sensing electrode and the sensing electrode and a first drain electrode and a second drain electrode, arranged such that the first sensing electrode, second sensing electrode, and source electrode are between the first drain electrode and the second drain electrode. The vertical Hall effect sensor also includes a plurality of semiconductor fingers disposed on the semiconductor wafer and interdigitated with the plurality of semiconductive electrodes, the semiconductor fingers having a second conductivity type.
    Type: Application
    Filed: March 4, 2016
    Publication date: June 30, 2016
    Applicant: Allegro Microsystems, LLC
    Inventors: Steven Kosier, Noel Hoilien
  • Patent number: 9379690
    Abstract: In one aspect, a duty cycle controller includes a first port configured to receive a voltage bias signal, a second port configured to receive an input voltage signal, a third port configured to provide an output signal of the duty cycle controller having a duty cycle and a n-bit digital-to-analog converter (DAC) configured to receive the voltage bias signal and to provide a DAC output signal to a comparator. The DAC output signal has a peak value. The duty cycle controller also includes the comparator configured to compare the DAC output signal from the n-bit DAC with the input voltage signal to provide a comparator output signal. The comparator output signal is used to provide the output signal of the duty cycle controller and the duty cycle changes with changes to the input voltage signal.
    Type: Grant
    Filed: February 24, 2014
    Date of Patent: June 28, 2016
    Assignee: ALLEGRO MICROSYSTEMS, LLC
    Inventors: George P. Humphrey, William E. Martin