Patents by Inventor Eric Shoemaker

Eric Shoemaker has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10234513
    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: Grant
    Filed: March 20, 2012
    Date of Patent: March 19, 2019
    Assignee: Allegro MicroSystems, LLC
    Inventors: Ravi Vig, William P. Taylor, Andreas P. Friedrich, Paul David, Marie-Adelaide Lo, Eric Burdette, Eric Shoemaker, Michael C. Doogue
  • Patent number: 10066965
    Abstract: A magnetic field sensor includes a magnetic field sensing element configured to generate a magnetic field signal; a measured threshold module configured to generate a measured threshold signal in accordance with positive peaks and negative peaks of the magnetic field signal; a memory device coupled to receive and configured to store, at each one of a plurality of storage times, a respective value of the measured threshold signal; a threshold module coupled to receive from the memory device, at a calculation time, a stored value of the measured threshold signal and configured to generate a calculated threshold value; and a comparison circuit coupled to receive the calculated threshold value and to receive the magnetic field signal. The comparison circuit is configured to compare the calculated threshold value with the magnetic field signal to generate an output signal. A corresponding method is associated with the magnetic field sensor.
    Type: Grant
    Filed: March 23, 2017
    Date of Patent: September 4, 2018
    Assignee: Allegro MicroSystems, LLC
    Inventors: Andrea Foletto, Peter Cisar, Eric Shoemaker
  • Publication number: 20170191852
    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: March 23, 2017
    Publication date: July 6, 2017
    Applicant: Allegro MicroSystems, LLC
    Inventors: Andrea Foletto, Peter Cisar, Eric Shoemaker
  • Patent number: 9664748
    Abstract: A magnetic field sensor and associated method provide an output signal with first and second different pulses with first and second different pulse widths indicative of first and second different directions of rotation of a moving target. The magnetic field sensor also includes third pulses with an identifiable encoding to indicate when a signature region in the moving target proximate to the magnetic field sensor passes by the magnetic field sensor. The third pulses each comprise respective state transitions and each comprise respective pulse widths with respective fixed predetermined time durations.
    Type: Grant
    Filed: June 17, 2014
    Date of Patent: May 30, 2017
    Assignee: Allegro Microsystems, LLC
    Inventors: Andreas P. Friedrich, Andrea Foletto, Jay M. Towne, Michael Morris, Eric Shoemaker
  • Patent number: 9644999
    Abstract: A magnetic field sensor includes a comparator coupled to receive a calculated threshold value based upon a temperature signal, a stored value of a temperature coefficient signal, and a stored value of a measure threshold signal, and also coupled to receive a signal representative of a magnetic field signal. The comparator is configured to compare the calculated threshold value with the signal representative of the magnetic field signal to generate an output signal. A corresponding method is associated with the magnetic field sensor.
    Type: Grant
    Filed: April 11, 2014
    Date of Patent: May 9, 2017
    Assignee: Allegro MicroSystems, LLC
    Inventors: Andrea Foletto, Peter Cisar, Eric Shoemaker
  • Patent number: 9182456
    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: Grant
    Filed: March 6, 2012
    Date of Patent: November 10, 2015
    Assignee: Allegro Microsystems, LLC
    Inventors: Eric Shoemaker, Michael C. Doogue, Andreas P. Friedrich, Andrea Foletto
  • Publication number: 20140375312
    Abstract: A magnetic field sensor and associated method provide an output signal with an identifiable encoding to indicate when a signature region in a moving target proximate to the magnetic field sensor passes by the magnetic field sensor.
    Type: Application
    Filed: June 17, 2014
    Publication date: December 25, 2014
    Applicant: ALLEGRO MICROSYSTEMS, LLC
    Inventors: Andreas P. Friedrich, Andrea Foletto, Jay M. Towne, Michael Morris, Eric Shoemaker
  • Publication number: 20140222364
    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: April 11, 2014
    Publication date: August 7, 2014
    Applicant: ALLEGRO MICROSYSTEMS, LLC
    Inventors: Andrea Foletto, Peter Cisar, Eric Shoemaker
  • Publication number: 20140145711
    Abstract: A circuit to detect a movement of an object includes a magnetic field sensing element for generating a magnetic field signal proportional to a magnetic field associated with the object and a motion detector to generate a motion signal indicative of the movement of the object. The motion detector includes a peak identifying circuit to provide a peak signal and a peak sample selection module that selects a sample associated with one or more prior cycles of a magnetic field signal to generate a selected peak signal. The motion detector further includes a threshold generator to generate a threshold signal as a function of the selected peak signal and a comparator to compare the threshold signal with the magnetic field signal to generate the motion signal. Peak samples from prior magnetic field signal cycles may be averaged for use to establish the threshold signal. A method associated with the circuit is also described.
    Type: Application
    Filed: November 26, 2012
    Publication date: May 29, 2014
    Inventors: Eric Burdette, James M. Bailey, Daniel S. Dwyer, Jeff Eagen, Glenn A. Forrest, Christine Graham, Eric Shoemaker, P. Karl Scheller
  • Patent number: 8736260
    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: Grant
    Filed: January 6, 2012
    Date of Patent: May 27, 2014
    Assignee: Allegro Microsystems, LLC
    Inventors: Andrea Foletto, Peter Cisar, Eric Shoemaker
  • Patent number: 8723512
    Abstract: A circuit to detect a movement of an object includes a magnetic field sensing element for generating a magnetic field signal proportional to a magnetic field associated with the object and a motion detector to generate a motion signal indicative of the movement of the object. The motion detector includes a peak identifying circuit to provide a peak signal and a peak sample selection module that selects a sample associated with one or more prior cycles of a magnetic field signal to generate a selected peak signal. The motion detector further includes a threshold generator to generate a threshold signal as a function of the selected peak signal and a comparator to compare the threshold signal with the magnetic field signal to generate the motion signal. Peak samples from prior magnetic field signal cycles may be averaged for use to establish the threshold signal. A method associated with the circuit is also described.
    Type: Grant
    Filed: November 26, 2012
    Date of Patent: May 13, 2014
    Assignee: Allegro Microsystems, LLC
    Inventors: Eric Burdette, James M. Bailey, Daniel S. Dwyer, Jeff Eagen, Glenn A. Forrest, Christine Graham, Eric Shoemaker, P. Karl Scheller
  • 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: 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: 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
  • 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: 20100181993
    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: Application
    Filed: January 19, 2009
    Publication date: July 22, 2010
    Inventors: Devon Fernandez, William P. Taylor, Michael Morris, P. Karl Scheller, Eric Shoemaker
  • Patent number: 7373515
    Abstract: A suspect user (110) seeks access to a network resource from an access authority (150) utilizing a passcode received from an authentication authority (130). Initially, an ID of a device is bound with a PIN, the device ID is bound with a private key of the device, and the device ID is bound with a user ID that has been previously bound with a password of an authorized user. The device ID is bound with the user ID by authenticating the user ID using the password. Thereafter, the suspect user communicates the device ID and the PIN from the device over an ancillary communications network (112); the authentication authority responds back over the ancillary communications network with a passcode encrypted with the public key of the device; and the suspect user decrypts and communicates over a communications network (114) the passcode with the user ID to the access authority.
    Type: Grant
    Filed: October 9, 2001
    Date of Patent: May 13, 2008
    Assignee: Wireless Key Identification Systems, Inc.
    Inventors: William N. Owen, Eric Shoemaker
  • Publication number: 20040187018
    Abstract: A suspect user (110) seeks access to a network resource from an access authority (150) utilizing a passcode received from an authentication authority (130). Initially, an ID of a device is bound with a PIN, the device ID is bound with a private key of the device, and the device ID is bound with a user ID that has been previously bound with a password of an authorized user. The device ID is bound with the user ID by authenticating the user ID using the password. Thereafter, the suspect user communicates the device ID and the PIN from the device over an ancillary communications network (112); the authentication authority responds back over the ancillary communications network with a passcode encrypted with the public key of the device; and the suspect user decrypts and communicates over a communications network (114) the passcode with the user ID to the access authority.
    Type: Application
    Filed: April 7, 2004
    Publication date: September 23, 2004
    Inventors: William N. Owen, Eric Shoemaker