Patents Assigned to Allegro Microsystems Inc.
  • Publication number: 20110298449
    Abstract: A motion sensor has an output protocol processor configured to provide a validated output signal after a determined time period, wherein the determined time period is extended if a vibration is detected.
    Type: Application
    Filed: June 3, 2010
    Publication date: December 8, 2011
    Applicant: Allegro Microsystems, Inc.
    Inventors: Andrea Foletto, Devon Fernandez, Eric Burdette
  • Publication number: 20110298450
    Abstract: A circuit to detect a movement of an object provides a threshold selection module that uses one or more threshold signals identified prior to a present cycle of magnetic field signal in order to establish a threshold signal used for a present cycle of the magnetic field signal. A method associated with the circuit is also described.
    Type: Application
    Filed: June 4, 2010
    Publication date: December 8, 2011
    Applicant: Allegro Microsystems, Inc.
    Inventors: Andrea Foletto, Andreas P. Friedrich
  • Publication number: 20110298448
    Abstract: A motion sensor has a channel amplitude difference processor configured to adjust gains of two channels to bring a gain of a one channel toward a gain of the other channel when a gain mismatch is detected.
    Type: Application
    Filed: June 3, 2010
    Publication date: December 8, 2011
    Applicant: Allegro Microsystems, Inc.
    Inventors: Andrea Foletto, Devon Fernandez, Eric Burdett
  • Publication number: 20110298447
    Abstract: A motion sensor has a state processor to identify states associated with a magnetic field signal provided by a magnetic field sensing element. The state processor includes a state peak logic module configured to generate states that have a reduced amount of state chatter.
    Type: Application
    Filed: June 3, 2010
    Publication date: December 8, 2011
    Applicant: Allegro Microsystems, Inc.
    Inventors: Andrea Foletto, Devon Fernandez, Eric Burdette
  • Patent number: 8063634
    Abstract: An electronic circuit includes a primary magnetoresistance element for providing a first output signal proportional to a magnetic field. The primary magnetoresistance element has a primary maximum response axis. The primary magnetoresistance element also has a hysteresis characteristic. The electronic circuit also includes a reset conductor disposed proximate to the magnetoresistance element. The electronic circuit also includes a secondary magnetic field sensing element for providing a second output signal proportional to a magnetic field. The secondary magnetic field sensing element has a secondary maximum response axis, which, in some embodiments, is substantially perpendicular to the primary maximum response axis. In operation, the primary magnetoresistance is reset in accordance with an excessive magnetic field sensed by the secondary magnetic field sensing element.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: November 22, 2011
    Assignee: Allegro Microsystems, Inc.
    Inventors: John Sauber, William P. Taylor
  • Patent number: 8058864
    Abstract: A magnetic field has a threshold that adapts in relation to a magnitude of a magnetic field signal representative of a movement of an object. A corresponding method adapts a threshold in relation to a magnitude of a magnetic field signal representative of a movement of an object.
    Type: Grant
    Filed: April 17, 2009
    Date of Patent: November 15, 2011
    Assignee: Allegro Microsystems, Inc.
    Inventors: P. Karl Scheller, Andreas P. Friedrich, William P. Taylor
  • Patent number: 8054071
    Abstract: A magnetic field sensor includes a linear magnetic field sensor to produce a voltage proportional to a sensed magnetic field and an interface having only two terminals for external connections. The two terminals of the interface include a power supply terminal and a ground terminal. The interface includes a voltage-controlled current generating device that is connected between the two terminals and is controlled by the voltage to provide a current signal that is proportional to the sensed magnetic field.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: November 8, 2011
    Assignee: Allegro Microsystems, Inc.
    Inventors: Michael C. Doogue, Jonathan Lamarre, Monica J. Thomas
  • Publication number: 20110248708
    Abstract: Methods for providing a magnetic sensor, including providing a signal generation module, providing 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, and providing a signal inversion module coupled to the signal generation module.
    Type: Application
    Filed: June 21, 2011
    Publication date: October 13, 2011
    Applicant: Allegro Microsystems, Inc.
    Inventors: Monica J. Thomas, Michael C. Doogue, Hooman Bustani
  • Patent number: 8030918
    Abstract: Magnetic field sensors have a magnetic field sensing element and also a feedback circuit to provide a gain-adjustment signal to affect a sensitivity associated with the magnetic field sensing element. In some arrangements, the feedback circuit can include piezoresistors to sense a strain of a substrate over which the magnetic field sensor is disposed. With these arrangements, the feedback circuit can generate the gain-adjustment signal in accordance with the sensed strain. In other arrangements, the feedback circuit can generate pulsed magnetic fields proximate to the magnetic field sensing element in order to directly measure the sensitivity of the magnetic field sensing element. With these arrangements, the feedback circuit can generate the gain-adjustment signal in accordance with the sensed sensitivity.
    Type: Grant
    Filed: December 3, 2010
    Date of Patent: October 4, 2011
    Assignee: Allegro Microsystems, Inc.
    Inventors: Michael C. Doogue, Gerardo Monreal, William P. Taylor
  • Patent number: 8022692
    Abstract: A sensor responsive to movement of a detection target includes a magnetic field transducer operative to provide a magnetic field signal proportional to a magnetic field associated with the detection target, a peak detector for tracking positive and negative peaks of the magnetic field signal to generate a tracking signal, and a comparator having a first input responsive to the magnetic field signal, a second input responsive to an input signal related to the tracking signal, and an output at which is provided an output signal comprising first pulses having a first pulse width when the detection target moves in a first direction and second pulses having a second pulse width when the detection target moves in a second direction.
    Type: Grant
    Filed: January 19, 2009
    Date of Patent: September 20, 2011
    Assignee: Allegro Microsystems, Inc.
    Inventors: Devon Fernandez, William P. Taylor, Michael Morris, P. Karl Scheller, Eric Shoemaker
  • Publication number: 20110221518
    Abstract: A switched capacitor notch filter for sampling an input signal using multiple sampling capacitors during multiple non-overlapping time periods. The charge from one set of sampling capacitors is averaged and transferred to the filter output during one non-overlapping time and the charge from another set of sampling capacitors is averaged and transferred to the filter output during a second non-overlapping time period.
    Type: Application
    Filed: March 12, 2010
    Publication date: September 15, 2011
    Applicant: Allegro Microsystems, Inc.
    Inventor: Hernan D. Romero
  • Patent number: 8008908
    Abstract: A magnetic field sensor for low power applications includes a magnetic field sensing element that, during sample intervals, provides a signal proportional to a sensed magnetic field and also includes a comparator circuit that, during the sample intervals, compares the magnetic field signal to threshold levels to generate a sensor output signal indicative of a strength of the magnetic field. According to a dual sample rate feature, initially the magnetic field signal is sampled at a first predetermined sample rate and, following detection of a transition of the sensor output signal, is sampled at a second, faster predetermined sample rate for a predetermined interval. According to a user-programmable sample rate feature, a user may select to operate the sensor at a fixed, predetermined sample rate or at a user-specified sample rate. The magnetic field sensor may also or alternatively detect the speed and/or direction of rotation of a rotating magnetic article.
    Type: Grant
    Filed: June 25, 2007
    Date of Patent: August 30, 2011
    Assignee: Allegro Microsystems, Inc.
    Inventors: Michael C. Doogue, Shaun D. Milano, Paul David
  • Publication number: 20110204460
    Abstract: An integrated circuit and a method of making the integrated circuit provide a Hall effect element having a germanium Hall plate. The germanium Hall plate provides an increased electron mobility compared with silicon, and therefore, a more sensitive Hall effect element.
    Type: Application
    Filed: February 19, 2010
    Publication date: August 25, 2011
    Applicant: Allegro Microsystems, Inc.
    Inventors: Harianto Wong, William P. Taylor, Ravi Vig
  • Patent number: 7999487
    Abstract: Electronic circuits and methods include provisions for passing a first current through a diode during a first time interval and for passing a second different current through the diode during a second different time interval. The first current is selected to achieve a predetermined voltage at a node of the diode. A duty cycle of the first current relative to the second current is selected to achieve a predetermined average current passing through the diode. In some arrangements, the diode is a light emitting diode.
    Type: Grant
    Filed: June 10, 2008
    Date of Patent: August 16, 2011
    Assignee: Allegro Microsystems, Inc.
    Inventor: Gregory Szczeszynski
  • Patent number: 7994774
    Abstract: A sensor includes a magnetic position sensing element to generate angular position information, a first signal generator, a second signal generator, a first inverter to invert the first waveform for providing a first inverted waveform and a second inverter to invert the second waveform for providing a second inverted waveform, wherein the first and second waveforms are inverted about an offset voltage, and an analog signal processing module to generate a linear output signal from the first waveform, the second waveform, the first inverted waveform, and the second inverted waveform.
    Type: Grant
    Filed: February 7, 2011
    Date of Patent: August 9, 2011
    Assignee: Allegro Microsystems, Inc.
    Inventors: Monica J. Thomas, Michael C. Doogue, Hooman Bustani
  • Patent number: 7990209
    Abstract: A switched capacitor notch filter for sampling an input signal using multiple sampling capacitors and multiple non-overlapping time periods. The charge from the sampling capacitors is averaged and transferred to the filter output during another non-overlapping time period.
    Type: Grant
    Filed: June 19, 2009
    Date of Patent: August 2, 2011
    Assignee: Allegro Microsystems, Inc.
    Inventor: Hernan D. Romero
  • Patent number: 7982454
    Abstract: A proximity detector employs a first peak detector circuit and a second peak detector circuit, both responsive to a magnetic field signal. The second peak detector circuit includes a positive peak detector circuit and a negative peak detector circuit, each of which have a predetermined excursion limit in an outward direction away from a center voltage of the magnetic field signal so as to be less affected by a large signature region in the magnetic field signal. The proximity detector also includes an output control circuit. The output control circuit is configured to provide an output signal, which, during a determined time period, changes state in response to the first peak detector circuit, and which, after the determined time period, changes state in response to the second peak detector circuit.
    Type: Grant
    Filed: June 26, 2007
    Date of Patent: July 19, 2011
    Assignee: Allegro Microsystems, Inc.
    Inventors: Devon Fernandez, Jeff Eagen, Glenn A. Forrest, Mathew Drouin
  • Patent number: 7973527
    Abstract: An electronic circuit includes a magnetoresistance element for providing an output signal proportional to a magnetic field. The magnetoresistance element also has a hysteresis characteristic. The electronic circuit also includes at least one of a reset conductor or a bias conductor disposed proximate to the magnetoresistance element. For embodiments having a reset conductor, the electronic circuit is configured to generate a reset current carried by the reset conductor in response to the comparison. In response to the reset current, the reset conductor is configured to generate a reset magnetic field at the magnetoresistance element to temporarily force the magnetoresistance element to a saturation region of the hysteresis characteristic.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: July 5, 2011
    Assignee: Allegro Microsystems, Inc.
    Inventors: William P. Taylor, Michael C. Doogue
  • Publication number: 20110133732
    Abstract: Methods and apparatus for providing an integrated circuit package device, comprising a conductive leadframe, a magnetic sensor element disposed on the leadframe, wherein the leadframe includes a slot configuration to reduce eddy current flow about the magnetic sensor, the slot configuration including a first slot generally perpendicular to a second slot, wherein the first slot extends under the sensor element.
    Type: Application
    Filed: December 3, 2009
    Publication date: June 9, 2011
    Applicant: Allegro Microsystems, Inc.
    Inventor: John B. Sauber
  • Publication number: 20110121825
    Abstract: A sensor includes a magnetic position sensing element to generate angular position information, a first signal generator, a second signal generator, a first inverter to invert the first waveform for providing a first inverted waveform and a second inverter to invert the second waveform for providing a second inverted waveform, wherein the first and second waveforms are inverted about an offset voltage, and an analog signal processing module to generate a linear output signal from the first waveform, the second waveform, the first inverted waveform, and the second inverted waveform.
    Type: Application
    Filed: February 7, 2011
    Publication date: May 26, 2011
    Applicant: Allegro Microsystems, Inc.
    Inventors: Monica J. Thomas, Michael C. Doogue, Hooman Bustani