Semiconductor Type Solid-state Or Magnetoresistive Magnetometers Patents (Class 324/252)
  • Patent number: 8907666
    Abstract: A scissor style magnetic sensor having a novel hard bias structure for improved magnetic biasing robustness. The sensor includes a sensor stack that includes first and second magnetic layers separated by a non-magnetic layer such as an electrically insulating barrier layer or an electrically conductive spacer layer. The first and second magnetic layers have magnetizations that are antiparallel coupled, but that are canted in a direction that is neither parallel with nor perpendicular to the air bearing surface by a magnetic bias structure. The magnetic bias structure includes a neck portion extending from the back edge of the sensor stack and having first and second sides that are aligned with first and second sides of the sensor stack. The bias structure also includes a tapered or wedged portion extending backward from the neck portion.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: December 9, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Quang Le, Simon H. Liao, Shuxia Wang, Guangli Liu, Yongchul Ahn
  • Patent number: 8907669
    Abstract: A closed loop current sensor has a primary conductor and a plurality of secondary conductors. Selected ones of the plurality of secondary conductors are selected and driven in a feedback loop.
    Type: Grant
    Filed: July 24, 2012
    Date of Patent: December 9, 2014
    Assignee: Allegro Microsystems, LLC
    Inventor: Craig S. Petrie
  • Patent number: 8901925
    Abstract: A magnetoresistive element formed by a strip of magnetoresistive material which extends on a substrate of semiconductor material having an upper surface. The strip comprises at least one planar portion which extends parallel to the upper surface, and at least one transverse portion which extends in a direction transverse to the upper surface. The transverse portion is formed on a transverse wall of a dig. By providing a number of magnetoresistive elements perpendicular to one another it is possible to obtain an electronic compass that is insensitive to oscillations with respect to the horizontal plane parallel to the surface of the Earth.
    Type: Grant
    Filed: September 10, 2012
    Date of Patent: December 2, 2014
    Assignee: STMicroelectronics S.r.l.
    Inventors: Benedetto Vigna, Simone Sassolini, Lorenzo Baldo, Francesco Procopio
  • Patent number: 8901924
    Abstract: A semiconductor process and apparatus provide a high-performance magnetic field sensor with three differential sensor configurations which require only two distinct pinning axes, where each differential sensor is formed from a Wheatstone bridge structure with four unshielded magnetic tunnel junction sensor arrays, each of which includes a magnetic field pulse generator for selectively applying a field pulse to stabilize or restore the easy axis magnetization of the sense layers to orient the magnetization in the correct configuration prior to measurements of small magnetic fields. The field pulse is sequentially applied to groups of the sense layers of the Wheatstone bridge structures, thereby allowing for a higher current pulse or larger sensor array size for maximal signal to noise ratio.
    Type: Grant
    Filed: February 21, 2011
    Date of Patent: December 2, 2014
    Assignee: EverSpin Technologies, Inc.
    Inventors: Bradley Engel, Phillip Mather
  • Publication number: 20140347047
    Abstract: A magnetoresistive sensor is provided. Specifically, multiple layers of or single layer of conductor line are formed at the same level as an insulating layer on a substrate as a bottom conductive layer. A magnetoresistive structure is formed on the bottom conductive layer and has opposite first surface and second surface. The second surface faces toward the substrate and is contacted with the bottom conductive layer. Afterward, another insulating layer is formed on the first surface, a slot is formed at the same level as the another insulating layer and a conductor line is formed in the slot and contacted with the first surface, so that one layer or multiple layers of conductor line can be formed as a top conductive layer. A lengthwise extending direction of each of the bottom and top conductor layers is intersected a lengthwise extending direction of the magnetoresistive structure with an angle.
    Type: Application
    Filed: August 12, 2014
    Publication date: November 27, 2014
    Applicant: Voltafield Technology Corporation
    Inventors: Nai-Chung Fu, Fu-Tai Liou
  • Publication number: 20140347039
    Abstract: A magnetic field sensing device can include two or more magnetic field sensors configured to detect a magnetic field in a current carrying conductor. The magnetic field sensing device also can include a phase detector electrically coupled to outputs of the two or more magnetic field sensors. The magnetic field sensing device further can include a phase indicator electrically coupled to the phase detector. The phase indictor can include a display that indicates when the two or more magnetic field sensors are in a position in relation to the current carrying conductor. Other embodiments are provided.
    Type: Application
    Filed: August 11, 2014
    Publication date: November 27, 2014
    Inventors: Shwetak N. Patel, Sidhant Gupta, Matthew S. Reynolds, Karthik Yogeeswaran
  • Patent number: 8896304
    Abstract: A magnetic sensor includes first and second MR elements, and an electrode electrically connecting the first and second MR elements to each other. The electrode includes a first portion having a first surface, a second portion having a second surface, and a coupling portion coupling the first and second portions to each other. The first surface is in contact with an end face of the first MR element. The second surface is in contact with an end face of the second MR element. Each of the first and second surfaces has a three-hold or higher rotationally symmetric shape. The diameter of a first inscribed circle inscribed in the outer edge of the first surface and the diameter of the second inscribed circle inscribed in the outer edge of the second surface are greater than the width of the coupling portion.
    Type: Grant
    Filed: February 26, 2013
    Date of Patent: November 25, 2014
    Assignee: TDK Corporation
    Inventor: Toshihide Suto
  • Publication number: 20140340081
    Abstract: A magnetic sensor includes a detection portion that includes first and second magnetic resistance elements. Each of the first and second magnetic resistance elements includes a pinned layer whose magnetic direction is fixed in a predetermined direction and a free layer whose magnetic direction changes in accordance with an external magnetic field. A resistance value of each of the first and second magnetic resistance elements changes in accordance with an angle between the magnetization direction of the pinned layer and the magnetization direction of the free layer. The first and second magnetic resistance elements are connected in series in a state where the magnetization directions of the pinned layers are perpendicular to each other. The detection portion outputs a middle point voltage of the first and second magnetic resistance elements as a detection signal.
    Type: Application
    Filed: August 28, 2012
    Publication date: November 20, 2014
    Applicant: DENSO CORPORATION
    Inventor: Norihiro Kurumado
  • Patent number: 8884615
    Abstract: A sensor unit for the measurement of a current in a conductor (1) comprising at least one magnetoresistive sensor (5, 6) located at a radial distance from the outer surface of the conductor (1) is disclosed, wherein the conductor (1) has a circular cross-section, and wherein it comprises at least one auxiliary coil (7) for the generation of a bias magnetic field (Hbias) to the magnetoresistive sensor (5, 6) strong enough for inducing magnetic saturation in the magnetoresistive sensor (5, 6) continuously during the whole current measurement process. Further the use of such a sensor and a method for measuring the current in the conductor using such a sensor unit are disclosed.
    Type: Grant
    Filed: July 22, 2008
    Date of Patent: November 11, 2014
    Assignee: ABB Research Ltd.
    Inventors: Rudolf Gati, Markus Abplanalp
  • Patent number: 8884616
    Abstract: Embodiments relate to xMR sensors, in particular AMR and/or TMR angle sensors with an angle range of 360 degrees. In embodiments, AMR angle sensors with a range of 360 degrees combine conventional, highly accurate AMR angle structures with structures in which an AMR layer is continuously magnetically biased by an exchange bias coupling effect. The equivalent bias field is lower than the external rotating magnetic field and is applied continuously to separate sensor structures. Thus, in contrast with conventional solutions, no temporary, auxiliary magnetic field need be generated, and embodiments are suitable for magnetic fields up to about 100 mT or more. Additional embodiments relate to combined TMR and AMR structures. In such embodiments, a TMR stack with a free layer functioning as an AMR structure is used. With a single such stack, contacted in different modes, a high-precision angle sensor with 360 degrees of uniqueness can be realized.
    Type: Grant
    Filed: June 22, 2011
    Date of Patent: November 11, 2014
    Assignee: Infineon Technologies AG
    Inventors: Juergen Zimmer, Klemens Pruegl
  • Patent number: 8884606
    Abstract: A current determiner comprising a first input conductor and a first current sensor, formed of a plurality of magnetoresistive, anisotropic, ferromagnetic thin-film layers at least two of which are separated from one another by a nonmagnetic layer positioned therebetween, and both supported on a first side of a substrate adjacent to but electrically isolated from one another with the first current sensor positioned in those magnetic fields arising from any input currents. A first shield/concentrator of a material exhibiting a substantial magnetic permeability is positioned on a second side of the substrate opposite the first side of the substrate. The substrate can include a monolithic integrated circuit structure containing electronic circuit components of which at least one is electrically connected to the first input conductor.
    Type: Grant
    Filed: April 27, 2011
    Date of Patent: November 11, 2014
    Assignee: NVE Corporation
    Inventors: John K. Myers, James M. Daughton
  • Publication number: 20140327437
    Abstract: This patent discloses a current sensor comprising a sensor bridge (14), which consists of several magnetic tunnel junction (MTJ) elements (R11, R12, R21, R22), a MTJ temperature compensation resistor (16), and a current lead (20), which are integrated onto the same chip. The current lead (20) is positioned close to the sensor bridge (14), and it is used to carry the test current (19). A permanent magnet (17) is arranged at the periphery of the MTJ temperature compensation resistor (16). The permanent magnet (17) rigidly aligns the magnetization direction (7) of the free layer of the MTJ temperature compensation resistor (16) anti-parallel to the magnetization direction (8) of a pinning layer; so that the MTJ temperature compensation resistor (16) remains in a high resistance state providing a resistance value that changes as a function of temperature. The sensor bridge (14) is connected in series with the MTJ temperature compensation resistor (16) in order to temperature compensate the sensor bridge (14).
    Type: Application
    Filed: October 30, 2012
    Publication date: November 6, 2014
    Inventors: Liansheng Han, Jianmin Bai, Wei Li, Songsheng Xue
  • Publication number: 20140327436
    Abstract: A power module includes a first substrate having a metallized side, a second substrate spaced apart from the first substrate and having a metallized side facing the metallized side of the first substrate, and a semiconductor die interposed between the first and second substrates. The semiconductor die has a first side connected to the metallized side of the first substrate and an opposing second side connected to the metallized side of the second substrate. The power module further includes a sensor connected to the metallized side of the first substrate and galvanically isolated from the metallized side of the second substrate. The sensor is aligned with a first metal region of the metallized side of the second substrate so that the sensor can measure a magnetic field generated by the first metal region.
    Type: Application
    Filed: May 3, 2013
    Publication date: November 6, 2014
    Inventor: Carlos Castro Serrato
  • Patent number: 8878530
    Abstract: A measuring method of contactless magnetic detection of relative movement along a trajectory between a main creation system and a measuring system sensitive to the direction of the magnetic field, the creation system creating a main magnetic field of direction that varies in a plane detected by the measuring system to determine the relative position along that trajectory. The method includes subjecting the measuring system to a compensation magnetic field of direction that is fixed and opposite to the direction of the maximum main magnetic field measured by the measuring system and delivered uniquely by the main creation system and in determining the direction of a magnetic field resulting from the combination of the main magnetic field and the compensation magnetic field by measuring the two mutually-orthogonal components of the resultant magnetic field respectively varying substantially as cosine and sine functions of the angle of the resultant magnetic field.
    Type: Grant
    Filed: November 26, 2010
    Date of Patent: November 4, 2014
    Assignee: Electricfil Automotive
    Inventor: Vincent Liebart
  • Patent number: 8878529
    Abstract: A method for monitoring the function of a sensor module including sensor which generates a measurement signal for a physical quantity to be determined and applies the measurement signal to an output terminal in an unchanged form or in processed form. In addition, a test signal is generated whose spectrum lies outside the spectrum of the measurement signal. The test signal is supplied at a place in the sensor from which it reaches the output terminal in unchanged form or in processed form only in the case of a functional sensor. An output signal present at the output terminal is compared with the test signal and a diagnosis signal is generated, which indicates whether the test signal is present at the output terminal. The test signal is filtered out of the output signal and the remaining signal is applied as the measurement signal at an output of the sensor module.
    Type: Grant
    Filed: March 23, 2011
    Date of Patent: November 4, 2014
    Assignee: Micronas GmbH
    Inventors: Dieter Baecher, David Muthers, Joerg Franke
  • Patent number: 8878531
    Abstract: Embodiments of the invention provide a current sensor including a conductive element and at least two magnetic field sensors. The conductive element includes at least three terminal areas and a common conductive area, wherein each of the at least three terminal areas is connected to the common conductive area to guide a current applied to the respective terminal area into the common conductive area. The at least two magnetic field sensors are arranged at different geometric positions adjacent to the common conductive area, wherein each of the at least two magnetic field sensors is configured to sense a magnetic field component of each current flowing into the common conductive area to provide a sensor signal based on the sensed magnetic field component.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: November 4, 2014
    Assignee: Infineon Technologies AG
    Inventors: Udo Ausserlechner, Wolfgang Scherr
  • Publication number: 20140320114
    Abstract: An electrical device includes a magnetic sensor circuitry (101) for detecting magnetic field and for generating a detection signal in response to the detected magnetic field, and a control circuitry (102) for controlling operation of the electrical device in accordance with the detection signal. The magnetic sensor circuitry is configured to detect a direction related to a deviation of the magnetic field from the magnetic field of the earth, and the control circuitry is configured to control the operation of the electrical device in accordance with the detected direction. The electrical device can be controlled by using e.g. a permanent magnet (105) for directing, to the magnetic sensor circuitry, magnetic field deviating from the magnetic field of the earth and having a desired orientation. Thus, the electrical device can be controlled without an electrical connector or a radio interface.
    Type: Application
    Filed: April 23, 2014
    Publication date: October 30, 2014
    Applicant: TELLABS OY
    Inventor: Kim ENKOVAARA
  • Publication number: 20140320124
    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: Application
    Filed: April 26, 2013
    Publication date: October 30, 2014
    Applicant: Allegro Microsystems, LLC
    Inventors: Paul David, Ravi Vig, William P. Taylor, Andreas P. Friedrich
  • Publication number: 20140320117
    Abstract: A magnetic sensor includes a plurality of magneto-resistive effect elements each configured by using a magneto-resistive effect film formed by laminating a pinned layer, a nonmagnetic layer, and a free layer in order from a side of a substrate. A first linear pattern is formed in a first portion on the substrate in a first direction. A second linear pattern is formed in a second portion on the substrate in a second direction. A magnetization direction of the first portion is different from a magnetization direction of the second portion. The magneto-resistive effect film is further formed on the substrate. Each of the plurality of magneto-resistive effect elements includes a pair of electrodes formed by the magneto-resistive effect film processed into a predetermined shape.
    Type: Application
    Filed: July 14, 2014
    Publication date: October 30, 2014
    Applicant: Hitachi Metals, Ltd.
    Inventors: Kenichi Meguro, Hiroyuki Hoshiya, Keizou Katou, Yasunori Abe
  • Publication number: 20140320125
    Abstract: Methods and apparatus for non-intrusive monitoring by sensing physical parameters such as electric and/or magnetic fields. Such apparatus and techniques may find application in a variety of fields, such as monitoring consumption of electricity, water, etc., in homes or businesses, for example, or industrial process monitoring.
    Type: Application
    Filed: April 28, 2014
    Publication date: October 30, 2014
    Inventors: Steven B. Leeb, James Paris, John Sebastian Donnal, Jinyeong Moon, Christopher Schantz
  • Patent number: 8872507
    Abstract: The present application discloses an integrated circuit comprising a circuit portion (100) coupled between first and second power supply lines (110; 120); a first switch (115, 135) coupled between the first power supply line (110, 120) and the circuit portion (100) for disconnecting the circuit portion from the first power supply line during an inactive mode of the circuit portion; and an arrangement (315, 335, 410) for, during said inactive mode, providing the circuit portion (100) with a fraction of its active mode power supply at least when averaged over said inactive mode to prevent the circuit portion voltage to drop below a threshold value. The present application further discloses a method for controlling such an integrated circuit.
    Type: Grant
    Filed: May 26, 2009
    Date of Patent: October 28, 2014
    Assignee: Koninklijke Philips N.V.
    Inventors: Rogier Adrianus Henrica Niessen, Willem Franke Pasveer
  • Publication number: 20140312895
    Abstract: A detachable current and voltage sensor provides an isolated and convenient device to measure current passing through a conductor such as an AC branch circuit wire, as well as providing an indication of an electrostatic potential on the wire, which can be used to indicate the phase of the voltage on the wire, and optionally a magnitude of the voltage. The device includes a housing that contains the current and voltage sensors, which may be a ferrite cylinder with a hall effect sensor disposed in a gap along the circumference to measure current, or alternative a winding provided through the cylinder along its axis and a capacitive plate or wire disposed adjacent to, or within, the ferrite cylinder to provide the indication of the voltage.
    Type: Application
    Filed: June 30, 2014
    Publication date: October 23, 2014
    Inventors: Gary D. Carpenter, Wael El-Essawy, Alexandre Peixoto Ferreira, Thomas Walter Keller, Juan C. Rubio, Michael A. Schappert
  • Publication number: 20140312894
    Abstract: A measuring device for measuring magnetic properties of the surroundings of the device includes at least one magnetoresistive element extending in a line direction, and a support field device generating a magnetic support field in an area over the line direction. A pre-magnetization device of one or more magnets are arranged at a distance from the sensor line in a direction vertical to the line direction and extending parallel to the line direction. The pre-magnetization device is arranged relative to the sensor line such that the fields of the pre-magnetization device and the support magnetic field overlap to provide an overlapping magnetic field with a field strength component pointing in the line direction that is greater at one location on the sensor line than the strength of a field component pointing vertically toward the line direction not in the direction of the height of the magnetoresistive element.
    Type: Application
    Filed: August 15, 2012
    Publication date: October 23, 2014
    Inventors: Axel Bartos, Armin Meisenberg, Reinhold Pieper
  • Patent number: 8854036
    Abstract: In a current detecting apparatus, a container member includes a substrate fixing portion, a core inner-edge positioning portions, and a lid member. The substrate fixing portion is a portion formed at a position outside an outer edge of a magnetic core, and to which a first portion of a circuit board is fixed. Two of the core inner-edge positioning portions come into contact with the magnetic core, and come into contact with the circuit board. The first portion, the second portion, and the third portion surround a magnetoelectric device, such as a Hall element, that detects a magnetic flux in a gap portion of the magnetic core. The lid-side substrate holding portion, with the container-side substrate holding portion, holds the circuit board tightly.
    Type: Grant
    Filed: October 19, 2012
    Date of Patent: October 7, 2014
    Assignee: Sumitomo Wiring Systems, Ltd.
    Inventors: Hirokatsu Nakajima, Satoru Chaen
  • Publication number: 20140292322
    Abstract: A magnetic sensor includes an MR element and a bias field generation unit. The MR element includes a magnetization pinned layer having a magnetization pinned in a direction parallel to an X direction, a free layer having a magnetization that varies depending on an X-direction component of an external magnetic field, and a nonmagnetic layer interposed between the magnetization pinned layer and the free layer. The magnetization pinned layer, the nonmagnetic layer and the free layer are stacked to be adjacent in a Y direction. The free layer receives an interlayer coupling magnetic field in a direction parallel to the X direction resulting from the magnetization pinned layer. The bias field generation unit applies a bias magnetic field to the free layer. The bias magnetic field includes a first component in a direction opposite to that of the interlayer coupling magnetic field and a second component in a Z direction.
    Type: Application
    Filed: February 25, 2014
    Publication date: October 2, 2014
    Applicant: TDK CORPORATION
    Inventors: Hiroshi YAMAZAKI, Yoshiyuki MIZOGUCHI, Satoshi ABE, Homare TOKIDA, Toshiyuki AYUKAWA
  • Publication number: 20140292321
    Abstract: A magnetic sensor includes an MR element and a pair of magnets. The MR element includes a magnetization pinned layer having a magnetization pinned in a direction parallel to an X direction, a free layer having a magnetization that varies depending on an X-direction component of an external magnetic field, and a nonmagnetic layer interposed between the magnetization pinned layer and the free layer. The magnetization pinned layer, the nonmagnetic layer and the free layer are stacked to be adjacent in a Y direction. The free layer receives an interlayer coupling magnetic field in a direction parallel to the X direction resulting from the magnetization pinned layer. The pair of magnets applies a bias magnetic field to the free layer. The bias magnetic field includes a first component in a direction opposite to that of the interlayer coupling magnetic field and a second component in a Z direction.
    Type: Application
    Filed: February 11, 2014
    Publication date: October 2, 2014
    Applicant: TDK CORPORATION
    Inventors: Hiroshi YAMAZAKI, Yoshiyuki MIZOGUCHI, Takahiro IMAI, Satoshi ABE, Homare TOKIDA
  • Patent number: 8847591
    Abstract: A current sensor includes a magnetic sensor including magnetoresistive sensors configured to detect induction fields generated by a measurement current passing through a current line, a magnetic field application unit configured to apply to the magnetoresistive sensors a magnetic field having a direction perpendicular to sensitivity directions of the magnetoresistive sensors; and a computing unit configured to calculate from an output of the magnetic sensor a compensation value for the output. The computing unit is configured to be capable of calculating the compensation value from the outputs of the magnetic sensor obtained in at least two states in which magnetic fields applied by the magnetic field application unit are different from each other.
    Type: Grant
    Filed: July 19, 2012
    Date of Patent: September 30, 2014
    Assignee: ALPS Green Devices Co., Ltd.
    Inventor: Hirofumi Fukui
  • Publication number: 20140287534
    Abstract: The present invention discloses highly sensitive magnetic heterojunction device consisting of a composite comprising ferromagnetic (La0.66Sr0.34MnO3) LSMO layer with ultra-thin ferrimagnetic CoFe2O4 (CFO) layer capable of giant resistive switching (RS) which can be tuned at micro tesla magnetic field at room temperature.
    Type: Application
    Filed: June 25, 2012
    Publication date: September 25, 2014
    Applicant: COUNCIL OF SCIENTIFIC & INDUSTRIAL RESEARCH
    Inventors: Satishchandra Balkrishna Ogale, Dipankar Das Sarma, Abhimanyu Singh Rana, Vishal Prabhakar Thakare, Anil Kumar Puri
  • Publication number: 20140285188
    Abstract: Detection of the rotation angle of a magnetic field using a magnetic sensor in which two sensor units are arranged at a predetermined angle with respect to each other is performed with a resolution of an angle smaller than 45° with a simple circuit configuration. A detection circuit is connectable to a magnetic sensor in which first and second sensor units are arranged, at a predetermined angle with respect to each other, each sensor unit having a bridge circuit of magnetoresistance elements. The detection circuit includes a first comparison circuit that compares output signals of the first or second sensor unit, a second comparison circuit that compares an output signal of the first sensor unit with an output signal of second sensor unit, and a rotation angle calculation circuit that calculates a rotation angle of a magnetic field based on the comparison results of the first and second comparison circuits.
    Type: Application
    Filed: February 7, 2014
    Publication date: September 25, 2014
    Applicant: Seiko Epson Corporation
    Inventor: Toshikazu KUWANO
  • Patent number: 8841904
    Abstract: A probe for detecting distortions in a material includes a probe body, a ferrite core in the probe body, an excitation coil encircling the ferrite core and adapted to generate eddy currents, further magnetic shielding surrounding the excitation coil, and at least one giant magnetoresistive (GMR) sensor disposed in magnetic field-communicating relationship with the excitation coil and off-center with respect to the excitation coil's axis.
    Type: Grant
    Filed: February 17, 2011
    Date of Patent: September 23, 2014
    Assignee: The Boeing Company
    Inventors: Steven K. Brady, Donald D. Palmer, Jr., Jeffrey R. Kollgaard
  • Patent number: 8841907
    Abstract: The size of a current detecting apparatus is reduced by employing a small magnetic core, and problems caused by excessive heat generation and vibrations of a bass bar are prevented. In a current detecting apparatus, a current detecting bass bar includes a through portion penetrating through a hollow portion of a magnetic core, and plate-shaped terminal portions continuing from both sides of the through portion. The through portion is formed to have a thickness larger than that of the terminal portions.
    Type: Grant
    Filed: February 8, 2012
    Date of Patent: September 23, 2014
    Assignee: Sumitomo Wiring Systems, Ltd.
    Inventors: Hirokatsu Nakajima, Satoru Chaen
  • Patent number: 8841906
    Abstract: A current sensor having a magnetic field sensor, and a variable current source connected to the magnetic field sensor, and a first differential amplifier, connected to the magnetic field sensor, for amplifying a first sensor voltage. A second differential amplifier is provided and the second differential amplifier is connected to the first differential amplifier and to the current source. In the case of the first sensor voltage, a first operating current is present at the magnetic field sensor and in the case of a second sensor voltage, a second operating current is present, whereby the second Hall voltage is smaller than the first sensor voltage and the second operating current is greater than the first operating current.
    Type: Grant
    Filed: October 22, 2012
    Date of Patent: September 23, 2014
    Assignee: Micronas GmbH
    Inventors: Klaus Heberle, Joerg Franke
  • Publication number: 20140266186
    Abstract: Provided are magnetic sensors, which include a magnetic tunnel junction (MTJ) magnetoresistive element, a first electrode contacting at least a portion of a surface of the MTJ magnetoresistive element and extending beyond an edge of the surface of the MTJ magnetoresistive element, and a second electrode contacting at least a portion of an opposing surface of the MTJ magnetoresistive element and extending beyond an edge of the opposing surface of the MTJ magnetoresistive element, where facing surfaces of the extending portions of the first and second electrodes are non-overlapping. Also provided are devices, systems and methods in which the subject magnetic sensors find use.
    Type: Application
    Filed: March 13, 2014
    Publication date: September 18, 2014
    Inventors: Sebastian J. Osterfeld, Shan Xiang Wang
  • Publication number: 20140266185
    Abstract: Magnetic field sensor designs that provide both increased directionality and proximate coupling desirable for improved directionality and sensitivity and methods for fabricating them.
    Type: Application
    Filed: February 26, 2014
    Publication date: September 18, 2014
    Inventor: Alan L. Sidman
  • Publication number: 20140266180
    Abstract: Embodiments relate to sensor systems and methods for detecting residual currents. In embodiments, a sensor comprises a magnetic core and a plurality of conductors passing through an aperture of the core. The magnetic core comprises a gap in the core itself, and a magnetic field sensor is arranged proximate to but not within this gap, in contrast with conventional approaches, in order to detect a net flux in the core. Advantageously, embodiments can be used in applications in which it is desired to detect AC or DC currents.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Applicant: Infineon Technologies AG
    Inventor: Udo Ausserlechner
  • Publication number: 20140266181
    Abstract: Methods and apparatus for magnetic field sensor having a sensing element, an analog circuit path coupled to the sensing element for generating an output voltage in response to a magnetic field applied to the sensing element, and a coil in proximity to the sensing element, the coil having a first terminal that is accessible external to the magnetic field sensor.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Applicant: Allegro Microsystems, Inc.
    Inventors: Shaun D. Milano, Michael C. Doogue, William P. Taylor
  • Publication number: 20140266184
    Abstract: A planarized 3-dimensional magnetic sensor chip includes a first magnetic sensing device, a second magnetic sensing device, a third magnetic sensing device and a magnetic flux bending concentrating structure on a circuit chip substrate, wherein the first magnetic sensing device and the second magnetic sensing device are used to measure the magnitude of flux in a first direction and a third direction together, and the third magnetic sensing device is used to measure the magnitude of flux in a second direction, the magnetic flux bending concentrating structure is used to bend the magnitude of flux in the third direction to the first direction, such that the magnitude of flux in the third direction can be measured by first magnetic sensing device and the second magnetic sensing device in the first direction.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Inventor: Meng-Huang Lai
  • Publication number: 20140266187
    Abstract: This document discusses, among other things, a first magnetic sensor configured to sense first and second components of a magnetic field in respective, orthogonal directions, using first, second, third, and fourth sense elements, each on an angled surface sloped with respect to a surface, each including respective first, second, third, and fourth longitudinal axes, each parallel to each other. Further, a second magnetic sensor on the same surface can sense second and third components of a magnetic field in respective, orthogonal directions, using first, second, third, and fourth sense elements, each on an angled surface sloped with respect to the first surface, each including respective first, second, third, and fourth longitudinal axes, each parallel to each other and orthogonal to the longitudinal axes of the first magnetic sensor.
    Type: Application
    Filed: March 18, 2014
    Publication date: September 18, 2014
    Inventor: Phil Mather
  • Patent number: 8836317
    Abstract: A current sensor includes, a current-measured wiring including parallel wiring sections in which portions of the same wiring are arranged in parallel such that electric current to be measured flows therein in opposite directions each other; a magnetism detection unit which is arranged between parallel wirings located in the parallel wiring sections and detects a magnetic field in a direction perpendicular to a plane formed by the parallel wirings; a current detection unit which detects electric current flowing in the current-measured wiring, based on the magnetic field detected by the magnetism detection unit; and a magnetic core surrounding the parallel wiring sections so as to intensify the magnetic field generated around the parallel wirings located in the parallel wiring sections when electric current flows in the wirings.
    Type: Grant
    Filed: May 4, 2010
    Date of Patent: September 16, 2014
    Assignee: SAE Magnetics (H.K.) Ltd.
    Inventor: Tamon Kasajima
  • Patent number: 8836327
    Abstract: The cost and size of an atomic magnetometer are reduced by attaching a vapor cell structure that has a vapor cell cavity to a base die that has a laser light source that outputs light to the vapor cell cavity, and attaching a photo detection die that has a photodiode to the vapor cell structure to detect light from the laser light source that passes through the vapor cell cavity.
    Type: Grant
    Filed: December 7, 2011
    Date of Patent: September 16, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: William French, Philipp Lindorfer, Peter J. Hopper, Roozbeh Parsa, Andrew James West, Byron Jon Roderick Shulver
  • Patent number: 8836324
    Abstract: Disclosed is an arrangement for high-resolution determination of positions on linear or circular ferromagnetic measuring rods (3) that have a teeth structure, said arrangement providing reliable results in an environment affected by magnetic interference. For this purpose, a magnetic field sensor (1) is placed at the point where the field of a permanent magnet (4) is at a maximum and is mounted across from the measuring rod (3) in such a way that the soft magnetic material of the measuring rod causes the field to strengthen further. The obtained field strength is sufficient to be able to use multilayer GMR sensors in which the resistance changes by more than 40 percent, thus allowing a high signal amplitude to be used for greater position resolution.
    Type: Grant
    Filed: May 20, 2008
    Date of Patent: September 16, 2014
    Assignee: Sensitec GmbH
    Inventors: Uwe Loreit, Joerg Traute, Jochen Schmitt
  • Patent number: 8829901
    Abstract: A method to measure a magnetic field is provided. The method includes applying an alternating drive current to a drive strap overlaying a magnetoresistive sensor to shift an operating point of the magnetoresistive sensor to a low noise region. An alternating magnetic drive field is generated in the magnetoresistive sensor by the alternating drive current. When the magnetic field to be measured is superimposed on the alternating magnetic drive field in the magnetoresistive sensor, the method further comprises extracting a second harmonic component of an output of the magnetoresistive sensor. The magnetic field to be measured is proportional to a signed amplitude of the extracted second harmonic component.
    Type: Grant
    Filed: November 4, 2011
    Date of Patent: September 9, 2014
    Assignee: Honeywell International Inc.
    Inventor: Bharat B. Pant
  • Publication number: 20140247044
    Abstract: A current sensor includes a first magnetic sensor and a second magnetic sensor which are configured to detect an induced magnetic field from target current to be measured flowing through a current line. The first and second magnetic sensors each include a magnetoresistive element that includes a free magnetic layer and a hard bias layer applying a bias magnetic field to the free magnetic layer. The bias magnetic field in the magnetoresistive element of the first magnetic sensor is oriented opposite to the bias magnetic field in the magnetoresistive element of the second magnetic sensor.
    Type: Application
    Filed: May 15, 2014
    Publication date: September 4, 2014
    Applicant: ALPS GREEN DEVICES CO., LTD.
    Inventor: Shinji MITSUYA
  • Publication number: 20140239948
    Abstract: A magnetic field verifier apparatus includes a magnetic field detection element configured to produce a voltage signal in response to an applied magnetic field wherein the voltage signal corresponds to the strength of the applied magnetic field. Substantially identical circuit boards or units are connected to a central unit or mother board to place magnetic field detection elements of each board or unit in an mutually approximately orthogonal relationship. A microcontroller is in communication with the voltage signal. The magnetic field verifier apparatus is configurable to sense particular field strengths at various frequencies and store the readings to provide the user with a reliable verification that a particular magnetic field strength has been produced in a particular environment.
    Type: Application
    Filed: May 2, 2014
    Publication date: August 28, 2014
    Applicant: Data Security, Inc.
    Inventor: Robert A. Schultz
  • Patent number: 8816683
    Abstract: Magnetic field sensing method and apparatus of this disclosure uses two tunneling magneto-resistor (TMR) devices. Angles of the free magnetizations of the two TMR devices with respect to a fixed direction are set in a first to fourth period. In the first to fourth period, the two TMR devices act as a TMR sensing unit and a zero-field reference unit by turns, and each of the conductance difference between the sensing unit and the zero field reference unit is also obtained in each of the first to fourth period. Finally, the four conductance differences are summed up.
    Type: Grant
    Filed: July 13, 2012
    Date of Patent: August 26, 2014
    Assignee: Industrial Technology Research Institute
    Inventors: Ding-Yeong Wang, Young-Shying Chen, Keng-Ming Kuo
  • Publication number: 20140232389
    Abstract: A measurement head (1) for a magnetoelastic sensor having a ferrite core (3). The core (3) has a first end (5), on which a field coil (9) which generates a magnetic field is fitted, and at least a second end (7), on which a magnetic field sensor (11, 41) is fitted.
    Type: Application
    Filed: August 8, 2012
    Publication date: August 21, 2014
    Applicant: SIEMENS AKTIENGESELLSCHAFT
    Inventors: Carl Udo Maier, Jochen Ostermaier
  • Publication number: 20140232390
    Abstract: A magnetoresistive component comprises a horizontal magnetoresistive layer and a nonparallel magnetoresistive layer. The horizontal magnetoresistive layer is disposed above a surface of a substrate and has a first side and a second side opposite the first side, along its extending direction. The nonparallel magnetoresistive layer is not parallel to the surface of the substrate and is physically connected to the horizontal magnetoresistive layer at the first side of the horizontal magnetoresistive layer.
    Type: Application
    Filed: April 28, 2014
    Publication date: August 21, 2014
    Applicant: Voltafield Technology Corp.
    Inventors: Nai-Chung Fu, Kuang-Ching Chen, Fu-Tai Liou
  • Publication number: 20140225604
    Abstract: A magnetic sensor that utilizes Rashba effect to generate spin polarization. The sensor eliminates the need for a pinned layer structure and therefore, greatly reduces the gap thickness of the sensor allowing for greatly improved data density. The sensor includes a two dimensional conductor adjacent to a magnetic free layer, that can also be separated from the free layer by a non-magnetic, electrically insulating barrier layer and that can also be constructed with or without side shields. A current flow through the two-dimensional conductor in a direction parallel with the air bearing surface causes a spin polarization oriented perpendicular to the air bearing surface. The voltage output of the sensor changes with changing magnetization direction of the free layer relative to spin polarization in the two dimensional conductor.
    Type: Application
    Filed: February 11, 2013
    Publication date: August 14, 2014
    Applicant: HGST Netherlands B.V.
    Inventors: Goran Mihajlovic, Petrus A. Van Der Heijden
  • Publication number: 20140225605
    Abstract: The present invention discloses a MTJ triaxial magnetic field sensor, comprising an X-axis bridge sensor that has a sensing direction along an X-axis, a Y-axis bridge sensor that has a sensing direction along a Y-axis, a Z-axis sensor that has a sensing direction along a Z-axis, and an ASIC chip connected with and matched to the X-axis, Y-axis, and Z-axis sensor chips. The Z-axis sensor includes a substrate and MTJ magnetoresistive elements deposited on the substrate. The Z axis magnetic field sensor is attached to the ASIC chip along an attachment edge, and an angle is formed between the sensor side of the Z axis magnetic field sensor and the adjacent attachment edge. The attachment edge angle is an acute angle or an obtuse angle. The resulting X, Y, and Z axes are mutually orthogonal. The above design provides a highly integrated sensor with high sensitivity, low power consumption, good linearity, wide dynamic range, excellent thermal stability, and low noise.
    Type: Application
    Filed: August 27, 2012
    Publication date: August 14, 2014
    Applicant: Multidimension Technology Co., Ltd
    Inventors: Xiaofeng Lei, Xiaojun Zhang, Wei Li, Songsheng Xue
  • Patent number: 8803518
    Abstract: Measuring apparatus for measuring magnetic properties of the area surrounding the measuring apparatus with a sensor row comprising at least two magnetoresistive sensor elements, which are arranged in a row that extends in a row direction, and a supporting field apparatus with generates a magnetic supporting field having a magnetic field component which points in the row direction and the field strength of which varies in the row direction, wherein this field strength profile in the row direction does not have a zero crossing and/or a maximum or minimum on at least two sensor edges of the sensor elements which for the sensor row, which sensor edges are arranged after one another in the row direction.
    Type: Grant
    Filed: July 17, 2009
    Date of Patent: August 12, 2014
    Assignee: MEAS Deutschland GmbH
    Inventors: Armin Meisenberg, Axel Bartos