Patents by Inventor Lakshman Withanawasam

Lakshman Withanawasam 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: 9104922
    Abstract: A solid state magnetic sensor for sensing magnetic information on a magnetic track is provided. The solid state magnetic sensor includes at least one half of a Wheatstone bridge including at least two legs, each of the at least two legs including at least a portion of a strip of magnetic material, and barber pole nonmagnetic shorting bars arranged on the portions of the strip forming the at least two legs of the at least one half of the Wheatstone bridge. An inner gap between parallel and adjacent strips of a respective at least two legs is on the order of a transition length on the magnetic track to be sensed.
    Type: Grant
    Filed: November 12, 2012
    Date of Patent: August 11, 2015
    Assignee: Honeywell International Inc.
    Inventors: Bharat B. Pant, Lakshman Withanawasam
  • Patent number: 8975891
    Abstract: A method to measure an applied magnetic field in a plane is provided. The method includes simultaneously applying a first and second alternating drive current to a respective first and second strap overlaying a magnetoresistive sensor so the magnetoresistive sensor is subjected to a periodically rotating magnetic drive field rotating in the plane in the magnetoresistive sensor. When the applied magnetic field to be measured is superimposed on the periodically rotating magnetic drive field rotating in the plane, the method includes extracting a second harmonic component of an output voltage output from the magnetoresistive sensor. The magnitude of the magnetic field to be measured in the plane is proportional to an amplitude of the extracted second harmonic component of the output voltage. The orientation of the magnetic field to be measured in the plane is related to a phase angle of the extracted second harmonic component of the output voltage.
    Type: Grant
    Filed: November 4, 2011
    Date of Patent: March 10, 2015
    Assignee: Honeywell International Inc.
    Inventors: Bharat B. Pant, Lakshman Withanawasam
  • Publication number: 20130334311
    Abstract: A solid state magnetic sensor for sensing magnetic information on a magnetic track is provided. The solid state magnetic sensor includes at least one half of a Wheatstone bridge including at least two legs, each of the at least two legs including at least a portion of a strip of magnetic material, and barber pole nonmagnetic shorting bars arranged on the portions of the strip forming the at least two legs of the at least one half of the Wheatstone bridge. An inner gap between parallel and adjacent strips of a respective at least two legs is on the order of a transition length on the magnetic track to be sensed.
    Type: Application
    Filed: November 12, 2012
    Publication date: December 19, 2013
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventors: Bharat B. Pant, Lakshman Withanawasam
  • Patent number: 8459112
    Abstract: Systems and methods for fabricating a multi-axis sensor are provided. In one implementation, a method comprises: fabricating a first die having a first active surface with first application electronics; fabricating a second die having a second active surface with second application electronics and a plurality of electrical connections that extend from the second application electronics to a side surface interface of the second die that is adjacent to the second active surface; aligning the side surface interface to be coplanar with the first active surface; and forming at least one electrical connection between the plurality of electrical connections and the first active surface.
    Type: Grant
    Filed: June 9, 2011
    Date of Patent: June 11, 2013
    Assignee: Honeywell International Inc.
    Inventors: Ryan W. Rieger, Lakshman Withanawasam, Ronald J. Jensen
  • Publication number: 20130116943
    Abstract: A method to measure an applied magnetic field in a plane is provided. The method includes simultaneously applying a first and second alternating drive current to a respective first and second strap overlaying a magnetoresistive sensor so the magnetoresistive sensor is subjected to a periodically rotating magnetic drive field rotating in the plane in the magnetoresistive sensor. When the applied magnetic field to be measured is superimposed on the periodically rotating magnetic drive field rotating in the plane, the method includes extracting a second harmonic component of an output voltage output from the magnetoresistive sensor. The magnitude of the magnetic field to be measured in the plane is proportional to an amplitude of the extracted second harmonic component of the output voltage. The orientation of the magnetic field to be measured in the plane is related to a phase angle of the extracted second harmonic component of the output voltage.
    Type: Application
    Filed: November 4, 2011
    Publication date: May 9, 2013
    Applicant: Honeywell International Inc.
    Inventors: Bharat B. Pant, Lakshman Withanawasam
  • Publication number: 20120313193
    Abstract: Systems and methods for fabricating a multi-axis sensor are provided. In one implementation, a method comprises: fabricating a first die having a first active surface with first application electronics; fabricating a second die having a second active surface with second application electronics and a plurality of electrical connections that extend from the second application electronics to a side surface interface of the second die that is adjacent to the second active surface; aligning the side surface interface to be coplanar with the first active surface; and forming at least one electrical connection between the plurality of electrical connections and the first active surface.
    Type: Application
    Filed: June 9, 2011
    Publication date: December 13, 2012
    Applicant: Honeywell International Inc.
    Inventors: Ryan W. Rieger, Lakshman Withanawasam, Ronald J. Jensen
  • Publication number: 20120299587
    Abstract: Systems and methods for three-axis magnetic sensors are provided. In one embodiment, a three-axis magnetic sensor formed on a single substrate comprises: an in-plane two-axis magnetic sensor comprising at least one of either a magnetic-resistance (MR) sensor or a magnetic-inductive (MI) sensor formed on the single substrate; and an out-of-plane magnetic sensor comprising a Hall effect sensor formed on the single substrate. The in-plane two-axis magnetic sensor measures magnetic fields in a first plane parallel to a plane of the substrate, and the out-of-plane magnetic sensor measures magnetic fields along an axis orthogonal to the first plane.
    Type: Application
    Filed: May 26, 2011
    Publication date: November 29, 2012
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventors: Ryan W. Rieger, Lakshman Withanawasam
  • Patent number: 8316552
    Abstract: Systems and methods for three-axis sensor chip packages are provided. In one embodiment, a directional sensor package comprises: a base; a first sensor die mounted to the base, the first sensor die having a first active sensor circuit and a first plurality of metal pads electrically coupled to the first active sensor circuit; a second sensor die mounted to the base, the second sensor die having a second active sensor circuit located on a first surface, and a second plurality of metal pads electrically coupled to the second active sensor circuit located on a second surface. The second sensor die is positioned such that the second active sensor circuit is oriented orthogonally with respect to the first active sensor circuit region and is perpendicular to the base. The second surface is adjacent to the first surface and angled with respect to a plane of the first surface.
    Type: Grant
    Filed: May 5, 2011
    Date of Patent: November 27, 2012
    Assignee: Honeywell International Inc.
    Inventors: Lakshman Withanawasam, Ryan W. Rieger, Bharat B Pant
  • Patent number: 8315793
    Abstract: An integrated sensor device is provided. The integrated sensor device comprises a first substrate including a surface portion and a second substrate coupled to the surface portion of the first substrate in a stacked configuration, wherein a cavity is defined between the first substrate and the second substrate. The integrated sensor device also comprises one or more micro-electro-mechanical systems (MEMS) sensors located at least partially in the first substrate, wherein the MEMS sensor communicates with the cavity. The integrated sensor device further comprises one or more additional sensors.
    Type: Grant
    Filed: June 3, 2009
    Date of Patent: November 20, 2012
    Assignee: Honeywell International Inc.
    Inventor: Lakshman Withanawasam
  • Publication number: 20120279077
    Abstract: Systems and methods for three-axis sensor chip packages are provided. In one embodiment, a directional sensor package comprises: a base; a first sensor die mounted to the base, the first sensor die having a first active sensor circuit and a first plurality of metal pads electrically coupled to the first active sensor circuit; a second sensor die mounted to the base, the second sensor die having a second active sensor circuit located on a first surface, and a second plurality of metal pads electrically coupled to the second active sensor circuit located on a second surface. The second sensor die is positioned such that the second active sensor circuit is oriented orthogonally with respect to the first active sensor circuit region and is perpendicular to the base. The second surface is adjacent to the first surface and angled with respect to a plane of the first surface.
    Type: Application
    Filed: May 5, 2011
    Publication date: November 8, 2012
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventors: Lakshman Withanawasam, Ryan W. Rieger, Bharat Pant
  • Publication number: 20100312468
    Abstract: An integrated sensor device is provided. The integrated sensor device comprises a first substrate including a surface portion and a second substrate coupled to the surface portion of the first substrate in a stacked configuration, wherein a cavity is defined between the first substrate and the second substrate. The integrated sensor device also comprises one or more micro-electro-mechanical systems (MEMS) sensors located at least partially in the first substrate, wherein the MEMS sensor communicates with the cavity. The integrated sensor device further comprises one or more additional sensors.
    Type: Application
    Filed: June 3, 2009
    Publication date: December 9, 2010
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventor: Lakshman Withanawasam
  • Publication number: 20090093981
    Abstract: A magnetic compass includes a magnetic sensor, an acceleration sensor, respective signal conditioning circuits in electronic communication with the sensors and a microprocessor. These components are arranged and structurally coupled to a single electronic package that supports the sensors, the signal conditioning circuits, and the microprocessor to provide a miniaturized magnetic compass. In addition, a temperature sensor may be coupled to the package to provide temperature compensation for at least some of the above-identified components.
    Type: Application
    Filed: October 5, 2007
    Publication date: April 9, 2009
    Applicant: HONEYWELL INTERNATIONAL INC.
    Inventor: Lakshman Withanawasam
  • Patent number: 7494920
    Abstract: A method of fabricating a vertically mountable integrated circuit (IC) package is presented. An integrated circuit is mounted on a printed circuit board (PCB) and electrically coupled to a bond pad on the PCB. The bond pad is coupled with a via that is embedded in the PCB. The IC, the bond pad, the via, and a portion of the PCB are singulated in order to create a vertically mountable IC package. The via is cut through cross-sectionally during singulation so as to expose a portion of the via and thereby provide a mountable area for the IC package. The IC package may be encapsulated or housed in a dielectric material. In addition, the via may be treated with a preservative or other s-uitable electroless metal plating deposition that prevents oxidation and promotes solderability.
    Type: Grant
    Filed: October 14, 2005
    Date of Patent: February 24, 2009
    Assignee: Honeywell International Inc.
    Inventors: Daniel McCarthy, Lakshman Withanawasam
  • Publication number: 20070090529
    Abstract: A method of fabricating a vertically mountable integrated circuit (IC) package is presented. An integrated circuit is mounted on a printed circuit board (PCB) and electrically coupled to a bond pad on the PCB. The bond pad is coupled with a via that is embedded in the PCB. The IC, the bond pad, the via, and a portion of the PCB are singulated in order to create a vertically mountable IC package. The via is cut through cross-sectionally during singulation so as to expose a portion of the via and thereby provide a mountable area for the IC package. The IC package may be encapsulated or housed in a dielectric material. In addition, the via may be treated with a preservative or other suitable electroless metal plating deposition that prevents oxidation and promotes solderability.
    Type: Application
    Filed: October 14, 2005
    Publication date: April 26, 2007
    Applicant: Honeywell International Inc.
    Inventors: Daniel McCarthy, Lakshman Withanawasam
  • Publication number: 20060152217
    Abstract: A method and system for calibrating a magnetic compass and/or verifying a compass calibration, using a calibration magnetic field produced by a field-generating coil within the magnetic compass is described. The field-generating coil is located near magnetometers within the magnetic compass. Passing a self-trimming current through the coil produces a magnetic field that acts on the magnetometers. Samples of an output signal from each magnetometer are taken to obtain digital values that indicate the output signal from each magnetometer. The digital values are used by a processor to determine one or more calibration coefficient for using calibrating the magnetic compass. The samples of the output signals are taken when a self-trimming current is passing through the coil and when the self-trimming current is not passing through the coil.
    Type: Application
    Filed: January 7, 2005
    Publication date: July 13, 2006
    Applicant: Honeywell International Inc.
    Inventor: Lakshman Withanawasam
  • Publication number: 20060132125
    Abstract: A magnetometer is disclosed that enables high resolution magnetometry using magnetoresistive sensors that consume less power. The magnetometer exploits the ability of the sensor to alter or modulate sensitivity via external means. This modulation effectively transfers the signal of interest from the noisy DC domain to the AC domain by applying an AC signal to a current strap in a magnetic field sensor. The AC signal causes a first magnetic field to be formed in a direction perpendicular to the current strap. A magnetic field sensing structure in the magnetic field sensor senses the first magnetic field. The magnetic field sensing structure uses the first magnetic field to sense a second magnetic field. The second magnetic field is an external magnetic field that is of interest. An output of the magnetic field sensing structure is an AC signal that is proportional to the second magnetic field. The AC signal may be further amplified and refined employing signal conditioning techniques.
    Type: Application
    Filed: December 16, 2004
    Publication date: June 22, 2006
    Applicant: Honeywell International Inc.
    Inventor: Lakshman Withanawasam
  • Publication number: 20060039090
    Abstract: A spin valve GMR sensor configured in a bridge configuration is provided. The bridge includes two spin valve element pairs. The spin valve elements include a free layer, a space layer, a pinned layer, and a bias layer. The bias layer includes a first bias layer and a second bias layer. The first and second spin valve element pairs are formed on separate metal layers and a current pulse is applied to the metal layers, which sets the direction of magnetization in the pinned layer of the first pair of spin valve elements to be antiparallel to the direction of magnetization in the pinned layer of the second pair of spin valve elements. The same effect can be accomplished by making the pinned layer substantially thicker than the second bias layer in the first spin valve element pair and the pinned layer is substantially thinner than the second bias layer in the second spin valve element pair and applying a magnetic field to the first and the second spin valve element pairs.
    Type: Application
    Filed: October 21, 2005
    Publication date: February 23, 2006
    Applicant: Honeywell International Inc.
    Inventors: Hong Wan, Lakshman Withanawasam
  • Publication number: 20060039091
    Abstract: A spin valve GMR sensor configured in a bridge configuration is provided. The bridge includes two spin valve element pairs. The spin valve elements include a free layer, a space layer, a pinned layer, and a bias layer. The bias layer includes a first bias layer and a second bias layer. The first and second spin valve element pairs are formed on separate metal layers and a current pulse is applied to the metal layers, which sets the direction of magnetization in the pinned layer of the first pair of spin valve elements to be antiparallel to the direction of magnetization in the pinned layer of the second pair of spin valve elements. The same effect can be accomplished by making the pinned layer substantially thicker than the second bias layer in the first spin valve element pair and the pinned layer is substantially thinner than the second bias layer in the second spin valve element pair and applying a magnetic field to the first and the second spin valve element pairs.
    Type: Application
    Filed: October 20, 2005
    Publication date: February 23, 2006
    Applicant: Honeywell International Inc.
    Inventors: Hong Wan, Lakshman Withanawasam