Calibration Patents (Class 324/202)
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Patent number: 8299783Abstract: A circuit to detect a movement of an object has a calibration time period that ends when peak detectors in the circuit stop updating for a predetermined amount of time. A method associated with the circuit is also described.Type: GrantFiled: August 27, 2009Date of Patent: October 30, 2012Assignee: Allegro Microsystems, Inc.Inventors: Devon Fernandez, Glenn A. Forrest
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Publication number: 20120268108Abstract: An exemplary current sensor operating in accordance with the principle of compensation includes a primary winding creating a magnetic field based on a current to be measured, a secondary winding generating a magnetic field compensating the primary winding based on a compensation current. The current sensor also includes a magnetic core, a terminating resistor connected in series to the secondary winding, and sensor means. A booster circuit is connected downstream of the sensor means and feeds the compensation current to the secondary winding via the terminating resistor. The booster circuit includes a switched mode amplifier with a pulse width and density modulator that operates based on pulse width and density modulation, turning the compensation current into a pulse width and density modulated current. The switched mode amplifier having a switching frequency that is high at when the compensation current is small and low when the compensation current is high.Type: ApplicationFiled: April 20, 2012Publication date: October 25, 2012Applicant: ABB AGInventors: Adrian HOZOI, Rolf Disselnkötter
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Patent number: 8290455Abstract: An accessory device for a field transmitter comprising an enclosure housing an electronic processing unit. Said device comprises a portable supporting body removably couplable with the transmitter and on which there are provided at least one activation unit which can be operated by a user, and an electronic processing circuit which is operatively interlocked with said activation unit and is suitable to be operatively connected to the electronics of the transmitter so as to transmit one or more signals thereto following actuation of the activation unit.Type: GrantFiled: March 19, 2007Date of Patent: October 16, 2012Assignee: ABB S.p.A.Inventors: Andrea Moroni, Ronaldo Dos Santos
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Publication number: 20120235670Abstract: Described herein are systems, devices, and methods that provide a stable magnetometer. The magnetometer includes a drive element that facilitates flow of a drive current through a node and a sense element operable to detect a magnetic field operating on the drive current. To reduce offset in the detection of the magnetic field, a voltage detector, electrically coupled to the drive element through the node, determines a variation between a node voltage and a target voltage. The voltage detector facilitates suppression of the variation and thereby minimizes the offset in the sense element.Type: ApplicationFiled: March 15, 2012Publication date: September 20, 2012Applicant: INVENSENSE, INC.Inventors: Baris Cagdaser, Derek Shaeffer, Joe Seeger, Chiung C. Lo
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Patent number: 8258780Abstract: Systems and methods for performing a self-test on a sensing device are described in the present disclosure. One implementation, among others, includes a method of performing a self test. In this implementation, the method includes supplying a periodic magnetic field upon a sensing element that is configured to sense a parameter of an object. The method further includes receiving an output from the sensing element indicating the operability of the sensing element. It should be noted that the output is received independently of the parameter of the object.Type: GrantFiled: September 10, 2008Date of Patent: September 4, 2012Inventor: William L. Smith
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Publication number: 20120210562Abstract: Manufacturing of magnetometer units (20?) employs a test socket (41) having a substantially rigid body (43) with a cavity (42) therein holding an untested unit (20) in a predetermined position (48) proximate electrical connection (50) thereto, wherein one or more magnetic field sources (281, 332, 333, 334, 335, 336) fixed in the body (43) provide known magnetic fields at the position (48) so that the response of each unit (20) is measured and compared to stored expected values. Based thereon, each unit (20) can be calibrated or trimmed by feeding corrective electrical signals back to the unit (20) through the test socket (41) until the actual and expected responses match or the unit (200) is discarded as uncorrectable. In a preferred embodiment, the magnetic field sources (281, 332, 333, 334, 335, 336) are substantially orthogonal coil pairs (332, 333, 334) arranged so that their centerlines (332-1, 333-1, 334-1) coincide at a common point (46) within the predetermined position (48).Type: ApplicationFiled: February 22, 2011Publication date: August 23, 2012Applicant: FREESCALE SEMICONDUCTOR, INC.Inventors: Peter T. Jones, David T. Myers, Franklin P. Myers, Jim D. Pak
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Publication number: 20120212214Abstract: Embodiments of the invention described herein provide a magnetic sensor interface capable of adjusting signal conditioning dynamically such that the true positive and negative peaks of the input signal are maintained for a given target across its entire speed range (0-Max rpm), therefore increasing the signal to noise ratio at low speeds and avoiding clipping or distortion at high speeds. In one aspect, a method comprises receiving an alternating differential voltage signal from a sensor. The alternating differential voltage signal has an amplitude that changes over time. The alternating differential voltage signal is converted to an attenuated single-ended voltage signal that can be dynamically scaled. The attenuated single-ended voltage signal can be scaled by multiplying the attenuated single-ended voltage signal by a scaling factor. The scaling factor is selected relative to a signal-to-noise ratio of the scaled attenuated single-ended voltage signal.Type: ApplicationFiled: February 23, 2011Publication date: August 23, 2012Inventors: James Merrill Roylance, Daniel Zahi Abawi, Biplab Deb
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Patent number: 8248063Abstract: An apparatus and a general method to measure a magnetic field using magneto-resistive sensors in an open-loop configuration are disclosed. A key feature is the regular in-situ normalization of the sensors to compensate for the effects of sensor aging.Type: GrantFiled: August 17, 2009Date of Patent: August 21, 2012Assignee: Headway Technologies, Inc.Inventors: Yuchen Zhou, Grace Gorman
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Publication number: 20120206129Abstract: A method and system are provided for calibrating a magnetometer of a mobile device. The method comprises displaying a visual indication of a gestural path on a display of the portable electronic device, monitoring for changes in orientation of the portable electronic device, changing the visual indication in response to the monitored changes in the orientation of the portable electronic device, measuring a magnetic field with the magnetometer, and calibrating the magnetometer in accordance with measurements of the magnetic field acquired at different points along the gestural path.Type: ApplicationFiled: August 26, 2011Publication date: August 16, 2012Applicant: RESEARCH IN MOTION LIMITEDInventors: Laura Mahan, Jeffrey Charles Bos, Przemyslaw Abratowski, Christopher Harris Snow, Steve Robert Grenier, Nazih Almalki
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Publication number: 20120166122Abstract: A method for reading a magnetic-field sensor provided with at least one first magnetoresistive element envisages generation of an output signal, indicative of a magnetic field, as a function of a detection signal supplied by the magnetic-field sensor. The reading method envisages: determining an offset signal present in the output signal; generating at least one compensation quantity as a function of the offset signal; and feeding back the compensation quantity at input to the reading stage so as to apply a corrective factor at input to the reading stage as a function of the compensation quantity, such as to reduce the value of the offset signal below a given threshold.Type: ApplicationFiled: February 23, 2012Publication date: June 28, 2012Applicant: STMICROELECTRONICS S.R.L.Inventors: Fabio Bottinelli, Carlo Alberto Romani, Carmela Marchese
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READING CIRCUIT FOR A MAGNETIC FIELD SENSOR WITH SENSITIVITY CALIBRATION, AND RELATED READING METHOD
Publication number: 20120153936Abstract: A reading circuit for a magnetic-field sensor, generating an electrical detection quantity as a function of a detected magnetic field and of a detection sensitivity, is provided with an amplification stage, which is coupled to the magnetic-field sensor and generates an output signal as a function of the electrical detection quantity and of an amplification gain. In particular, the amplification gain is electronically selectable, and the reading circuit is moreover provided with a calibration stage, integrated with the amplification stage and configured so as to vary a value of the amplification gain in such a way as to compensate a variation of the detection sensitivity with respect to a nominal sensitivity value.Type: ApplicationFiled: November 22, 2011Publication date: June 21, 2012Applicant: STMICROELECTRONICS S.R.LInventors: Carlo Alberto Romani, Enrico Pozzati, Fabio Bottinelli -
Publication number: 20120153937Abstract: Described herein is a biasing circuit for a magnetic-field sensor; the magnetic-field sensor is provided with a first detection structure, which generates a first electrical detection quantity as a function of a first component of an external magnetic field, and a second detection structure, which generates a second electrical detection quantity as a function of a second component of an external magnetic field. The biasing circuit electrically supplies the first detection structure and the second detection structure in respective biasing time intervals, at least partially distinct from one another, which preferably do not temporally overlap one other.Type: ApplicationFiled: December 20, 2011Publication date: June 21, 2012Applicant: STMICROELECTRONICS S.R.L.Inventors: Enrico Pozzati, Carlo Alberto Romani, Fabio Bottinelli
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Patent number: 8203329Abstract: A calibratable magnetic field sensor for sensing a first and a second spatial component of a magnetic field in a reference point, wherein the magnetic field includes a first and a second measurement field component and/or a first and a second calibration field component. The magnetic filed sensor includes a first sensor element arrangement including at least a first and a second sensor element for sensing the first magnetic field component, which includes a first measurement field component and/or a first calibration field component, with respect to a first spatial axis in the reference point. Furthermore, the magnetic field sensor includes a second sensor element arrangement for sensing the second magnetic field component, which includes a second measurement field component and/or a second calibration field component, with respect to a second spatial axis in the reference point.Type: GrantFiled: August 19, 2008Date of Patent: June 19, 2012Assignee: Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung E.V.Inventors: Hans-Peter Hohe, Michael Hackner, Markus Stahl-Offergeld
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Patent number: 8198899Abstract: A marine electromagnetic sensor system includes a sensor cable having at least one electromagnetic sensor thereon. A first calibration electrode is disposed on the cable on one side of the sensor. A second calibration electrode is disposed on the cable on an opposite side of the sensor. A calibration power supply is coupled to the first and second calibration electrodes. A measuring circuit is coupled to the sensor. A method for calibrating marine electromagnetic survey electrodes includes imparting electric current between calibration electrodes disposed at spaced apart locations on a cable deployed in the water. Voltages impressed across a pair of electrodes disposed on the cable between the calibration electrodes are detected in response to the current. A change in sensitivity of the at least one pair of electrodes is determined using the detected voltages.Type: GrantFiled: March 16, 2009Date of Patent: June 12, 2012Assignee: PGS Geophysical ASInventor: Ulf Peter Lindqvist
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Publication number: 20120143548Abstract: A dynamically self-adjusting magnetometer is disclosed. In one embodiment, a first sample module periodically generates an electronic signal related to at least one magnetic field characteristic of a monitored environment. A second sample module periodically generates an electronic signal related to at least one magnetic field characteristic of a monitored environment. A summing module sums the absolute value of the electronic signal from the first sample module and the electronic signal from the second sample module. A delta comparator module receives the electronic signals from each of the first sample module, the second sample module and the summing module and compares each of the electronic signals with a previously received set of electronic signals to establish a change, wherein an output is generated if the change is greater than or equal to a threshold.Type: ApplicationFiled: December 6, 2010Publication date: June 7, 2012Inventor: Cory James STEPHANSON
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Publication number: 20120133356Abstract: In one embodiment a method to compensate for the sensitivity drift of a magnetic field sensor for sensing a magnetic field comprises forming a reference magnetic field having first magnetic field parameters, e.g. a first amplitude and/or direction, in a first step and second magnetic field parameters, a second amplitude and/or direction, in a second step and a bias signal is formed without adjusting the bias signal with a feedback signal derived from an output signal of the magnetic field sensor.Type: ApplicationFiled: January 26, 2012Publication date: May 31, 2012Inventors: Olivier Charlier, Francois Laulanet, Mustafa Badaroglu
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Patent number: 8183859Abstract: An apparatus for calibrating a metal detecting device of a materials processing line. A placement arm is provided to control the path of a calibrating sample in order to simulate movement of tramp metal moving on a processing line along with materials being processed. Upper and lower arms of the placement arm are joined by an adjustable elbow which can be set to a maximum angle of extension in order to accurately place the calibrating sample at a preferred location in a detecting field of the metal detecting device.Type: GrantFiled: June 15, 2009Date of Patent: May 22, 2012Assignee: Carmeuse Lime, Inc.Inventors: Brandon Lee Bentley, Jeffery Shane Lippert
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Publication number: 20120098525Abstract: A method and system are provided for calibrating a magnetometer. The method comprises detecting a change in a physical configuration of the mobile device; applying at least one stored calibration parameter as a respective active calibration parameter when one or more stored calibration parameters corresponding to the detected physical configuration change are accessible by the mobile device; and performing a calibration to obtain at least one additional calibration parameter when the at least one additional calibration parameter is needed and applying the at least one additional calibration parameter as a respective active calibration parameter.Type: ApplicationFiled: September 19, 2011Publication date: April 26, 2012Applicant: RESEARCH IN MOTION LIMITEDInventors: Christopher Harris SNOW, Nazih ALMALKI, Adam Louis PARCO
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Publication number: 20120098524Abstract: A method and system are provided for performing a background calibration of a magnetometer. The method comprises obtaining a plurality of magnetometer readings; applying an active set of calibration parameters to the plurality of magnetometer readings to obtain a plurality of values; applying a new set of calibration parameters to the plurality of magnetometer readings to obtain a plurality of further values; applying an active set of calibration parameters to the plurality of magnetometer readings to obtain a plurality of further values; and replacing the active set of calibration parameters with the new set of calibration parameters when a quality of the plurality of values is higher than a quality of the further values.Type: ApplicationFiled: September 19, 2011Publication date: April 26, 2012Applicant: RESEARCH IN MOTION LIMITEDInventors: Christopher Harris Snow, Nazih Almalki, Sean Bartholomew Simmons
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Publication number: 20120096921Abstract: A method and system are provided for calibrating a magnetometer. The method comprises determining a current quality level associated with magnetometer readings obtained using an active set of calibration parameters; and lowering a quality threshold for a background calibration of the magnetometer when the current quality level exceeds a threshold quality level needed by an application utilizing the magnetometer readings.Type: ApplicationFiled: September 19, 2011Publication date: April 26, 2012Applicant: RESEARCH IN MOTION LIMITEDInventors: Nazih ALMALKI, Christopher Harris SNOW, Jeffrey Alton Hugh DODS, Adam Louis PARCO
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Publication number: 20120098523Abstract: A system includes an object in a space to generate an induced field; coils that generate a driving field; a detecting coil that detects a synthetic field of the driving field and the induced field; a unit that detects a driving current through the coil in synchronization with field detection by the detecting coil; a calculating unit that calculates a position and a direction of the object based on a detection value of the synthetic field and a detection value of the driving current; and a unit that calculates a phase of a driving field component which corresponds to the driving field at the detection value of the synthetic field, based on the detection value. The calculating unit obtains a component having a phase difference approximately orthogonal to the phase of the driving field component and calculates the position and direction of the object based on the obtained component.Type: ApplicationFiled: August 15, 2011Publication date: April 26, 2012Applicant: OLYMPUS MEDICAL SYSTEMS CORP.Inventor: Takahiro IIDA
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Publication number: 20120101762Abstract: A method and system are provided for calibrating a magnetometer. The method comprises obtaining a plurality of magnetometer sensor readings; storing sensor readings from the plurality of obtained sensor readings that are different; determining a first calibration parameter based on a first predetermined number of different readings; and determining a plurality of calibration parameters based on a second predetermined number of different readings, wherein the plurality of calibration parameters includes the first calibration parameter.Type: ApplicationFiled: September 19, 2011Publication date: April 26, 2012Applicant: Research In Motion LimitedInventors: Nazih Almalki, Christopher Harris Snow, Sean Bartholomew Simmons
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Publication number: 20120101766Abstract: A method and system are provided for calibrating a magnetometer. The method comprises applying at least one first test to a new set of calibration parameters; accepting the new set of calibration parameters as an active set of calibration parameters when the new calibration parameters pass the at least one first test; applying the active set of calibration parameters to a plurality of magnetometer readings to obtain a plurality of values; applying at least one second test to the plurality of values; and calculating a quality measure for the active set of calibration parameters based on an outcome of the at least one second test.Type: ApplicationFiled: September 19, 2011Publication date: April 26, 2012Applicant: RESEARCH IN MOTION LIMITEDInventors: Christopher Harris Snow, Nazih Almalki
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Publication number: 20120086438Abstract: A real-time calibration system and method for a mobile device having an onboard magnetometer uses an estimator to estimate magnetometer calibration parameters and a magnetic field external to the mobile device (e.g., the earth magnetic field). The calibration parameters can be used to calibrate uncalibrated magnetometer readings output from the onboard magnetometer. The external magnetic field can be modeled as a weighted combination of a past estimate of the external magnetic field and the asymptotic mean of that magnetic field, perturbed by a random noise (e.g., Gaussian random noise). The weight can be adjusted based on a measure of the statistical uncertainty of the estimated calibration parameters and the estimated external magnetic field. The asymptotic mean of the external magnetic field can be modeled as a time average of the estimated external magnetic field.Type: ApplicationFiled: October 6, 2010Publication date: April 12, 2012Applicant: APPLE INC.Inventor: Xiaoyuan Tu
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Patent number: 8154281Abstract: A system including a spinning current Hall sensor and a chopping circuit. The spinning current Hall sensor is configured to provide input signals and the chopping circuit is configured to receive the input signals. Spinning phases of the spinning current Hall sensor are lengthened in residual offset adjustment phases to obtain signals that correspond to the residual offset voltages of the spinning phases.Type: GrantFiled: April 9, 2009Date of Patent: April 10, 2012Assignee: Infineon Technologies AGInventor: Mario Motz
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Publication number: 20120068692Abstract: Some embodiments can concern a method of using a power consumption measurement device. The power consumption measurement device can be mechanically coupled to a surface of a circuit breaker box overlying at least part of one or more main electrical supply conductors for an electrical power infrastructure of a structure.Type: ApplicationFiled: July 1, 2011Publication date: March 22, 2012Applicant: Belkin International, Inc.Inventors: Shwetak N. Patel, Sidhant Gupta, Matthew S. Reynolds, Karthik Yogeeswaran
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Publication number: 20120062215Abstract: A magnetic-balance-system current sensor includes: a magnetoresistive element, a resistance value of the magnetoresistive element being changed by applying an induction magnetic field generated by a measurement target current; magnetic cores disposed near the magnetoresistive element; a feedback coil disposed near the magnetoresistive element and configured to generate a cancelling magnetic field that cancels out the induction magnetic field; and a magnetic-field detecting bridge circuit having two outputs. The measurement target current is measured on the basis of a current flowing through the feedback coil when the induction magnetic field and the induction magnetic field and the cancelling magnetic field cancel each other out. The feedback coil, the magnetic cores, and the magnetic-field detecting bridge circuit are formed on a same substrate. The feedback coil is of a spiral type, and the magnetic cores are provided above and below the feedback coil.Type: ApplicationFiled: November 18, 2011Publication date: March 15, 2012Applicant: ALPS GREEN DEVICES CO., LTD.Inventors: Yosuke IDE, Masamichi SAITO, Akira TAKAHASHI, Tsuyoshi NOJIMA, Shigenobu MIYAJIMA, Naoki SAKATSUME, Kenji ICHINOHE, Yoshihiro NISHIYAMA, Tatsuya KOGURE, Hidekazu KOBAYASHI, Masahiro IIZUKA
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Patent number: 8134358Abstract: The present invention provides a method to compensate for the sensitivity drift of a magnetic field sensor for sensing a magnetic field. The magnetic field sensor comprises at least four electrodes. The method comprises a first step where a first set of two electrodes is used to bias the sensor and a second set of two electrodes is used to sense an output signal of the magnetic field sensor, and a second step where the second set of two electrodes is used to bias the sensor and the first set of two electrodes is used to sense an output signal of the magnetic field sensor. The method is characterized in that at least one of the first or the second step is subdivided in at least a first sub-step and a second sub-step. A reference magnetic field has first magnetic field parameters, e.g. a first amplitude and/or direction, in the first sub-step and second magnetic field parameters, a second amplitude and/or direction, in the second sub-step.Type: GrantFiled: October 16, 2007Date of Patent: March 13, 2012Assignee: Semiconductor Components Industries, LLCInventors: Olivier Charlier, Francois Laulanet, Mustafa Badaroglu
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Publication number: 20120056615Abstract: An apparatus includes a sensor arrangement with a sensor chip. A magnetic field generator is configured to generate a secondary magnetic field opposing an external primary magnetic field at the sensor chip. The magnetic field generator protects the sensor arrangement against the external primary magnetic field.Type: ApplicationFiled: November 9, 2011Publication date: March 8, 2012Applicant: INFINEON TECHNOLOGIES AGInventors: Udo Ausserlechner, Thomas Bever, Dirk Hammerschmidt, Joachim Weitzel
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Patent number: 8132040Abstract: Systems and methods are disclosed herein to provide channel-to-channel skew control in accordance with one or more embodiments of the present invention. For example in accordance with an embodiment, a method of adjusting skew between first and second channels includes receiving a first channel output signal and a second channel output signal from the first and second channels, respectively; detecting a phase difference between the first channel output signal and the second channel output signal; and controlling, based on the detected phase difference, a signal delay within at least the first channel or the second channel to reduce skew between the first channel output signal and the second channel output signal.Type: GrantFiled: October 25, 2007Date of Patent: March 6, 2012Assignee: Lattice Semiconductor CorporationInventor: Robert Bartel
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Publication number: 20120025808Abstract: A method for measuring an angular position of a rotating shaft, the method including providing a magnetic field which rotates with the shaft about an axis of rotation, positioning an integrated circuit having first and second magnetic sensing bridges within the magnetic field at a radially off-center position from the axis of rotation, the first and second magnetic sensing bridges respectively providing first and second signals representative of first and second magnetic field directions, the integrated circuit having a set of adjustment parameters for modifying attributes of the first and second signals, modifying values of the set of adjustment parameters until errors in the first and second signals are substantially minimized, and determining an angular position of the shaft based on the first and second signals.Type: ApplicationFiled: October 6, 2011Publication date: February 2, 2012Applicant: INFINEON TECHNOLOGIES AGInventors: Wolfgang Granig, Dirk Hammerschmidt, Udo Ausserlechner
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Patent number: 8106647Abstract: A rotation sensor for detecting rotation of an object includes a semiconductor substrate, a vertical Hall element, and a magnetoresistive element. The vertical Hall element is formed in the semiconductor substrate to detect a magnetic field parallel to a surface of the semiconductor substrate. The vertical Hall element outputs a detection signal corresponding to the detected magnetic field. The magnetoresistive element is formed on the surface of the semiconductor substrate and has a resistance value changing with strength of the magnetic field. The magnetoresistive element outputs a resistance signal corresponding to the resistance value. The rotation is detected based on the detection signal and the resistance signal.Type: GrantFiled: August 6, 2009Date of Patent: January 31, 2012Assignee: DENSO CORPORATIONInventor: Satoshi Oohira
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Patent number: 8099852Abstract: A method for assembling an image capturing device is provided. The image capturing device includes a light-pervious module, an image sensor and a binding material. The image sensor has a light sensing region for converting an imaging light into an electronic signal. The binding material is used for binding articles together and curable by a curing process. Firstly, the light-pervious module and the image sensor together are releasably bound together via the binding material, thereby defining a close space for accommodating the image sensor. Then, a testing process is performed to detect a clean condition of the close space. If particles present in the close space are detected, the light-pervious module is detached from the image sensor, a cleaning process is done to remove the particle, and the light-pervious module and the image sensor are releasably bound together to define the close space again. Afterwards, the binding material is cured.Type: GrantFiled: March 6, 2009Date of Patent: January 24, 2012Assignee: Primax Electronics Ltd.Inventor: Jui-Hsiang Lo
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Publication number: 20120016614Abstract: A magnetic field sensor for detecting first, second, and third spatial components of a magnetic field at a reference point includes a first sensor element arrangement for detecting the first magnetic field component having a first measurement field component and a first calibration field component with respect to a first spatial axis at a reference point, a second sensor element arrangement for detecting the second magnetic field component having a second measurement field component and a second calibration field component with respect to a second spatial axis y at the reference point and a third sensor element arrangement for detecting the third magnetic field component having a third measurement field component and a third calibration field component with respect to a third spatial axis x at the reference point.Type: ApplicationFiled: June 27, 2007Publication date: January 19, 2012Inventors: Hans-Peter Hohe, Michael Hackner, Markus Stahl-Offergeld
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Publication number: 20110316526Abstract: The present invention relates to an arrangement (10) for measuring small amounts of a first medium (202) in a third medium (206) and/or of a substance in the first medium (202), said third medium (206) comprising said first medium (202) and a second medium (204), said second medium (204) comprising a known concentration of a magnetic material, wherein said arrangement comprises: magnetization means (12) for providing a variable magnetic field (20) in a region of action (22), in which a probe (18; 208) of said third medium (206) is placed for measurement, receiving means (14) for acquiring a detection signal of the magnetization of said probe (12) in said region of action (22) after application of said variable magnetic field (20), and evaluation means (214) for evaluating said detection signal and comparing it to calibration measurements of the magnetization of at least one calibration sample to derive an information about the amount of said first medium (202) in said third medium (206) and/or of said substanType: ApplicationFiled: March 1, 2010Publication date: December 29, 2011Applicant: KONINKLIJKE PHILIPS ELECTRONICS N.V.Inventors: Giovanni Nisato, Hans Marc Bert Boeve
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Publication number: 20110301897Abstract: A method for calibrating a triaxial magnetic field sensor includes steps for determining an offset of recorded measured values of the magnetic field sensor using a superposed signal and for determining the sensitivity of the magnetic field sensor along the first measuring axes. The determination of the sensitivity includes steps for determining the sensitivity of the magnetic field sensor along a first measuring axis and for determining the sensitivity of the magnetic field sensor along the other measuring axes based on the sensitivity of the first measuring axis and the determined offset.Type: ApplicationFiled: May 5, 2011Publication date: December 8, 2011Inventors: Stefan WEISS, Julian Bartholomeyczik, Sergej Scheiermann
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Patent number: 8072208Abstract: An integrated circuit including an amplifier and a first circuit. The amplifier is configured to receive a sensed signal and provide an amplified signal. The first circuit is configured to track a first signal that is based on the amplified signal. The first circuit includes a first comparator, tracking logic and a first digital to analog converter. The first comparator is configured to respond to a second signal that is based on the first signal and provide a comparator output signal. The tracking logic is configured to receive the comparator output signal and update a digital output. The first digital to analog converter is configured to receive the digital output and provide a tracking signal that is summed with the first signal to provide the second signal.Type: GrantFiled: May 30, 2008Date of Patent: December 6, 2011Assignee: Infineon Technologies AGInventor: Mario Motz
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Patent number: 8044660Abstract: An arrangement for influencing and/or detecting magnetic particles, and/or calibrating such an arrangement includes generating a magnetic selection field having a magnetic field strength pattern such that a first sub-zone having a low magnetic field strength and a second sub-zone having a higher magnetic field strength are formed in the region of action. A driver changes the position in space of the two sub-zones in the region of action by magnetic drive field so that the magnetization of the magnetic particles changes locally. The arrangement includes a drive signal chain, a detection signal chain, and a receiver for acquiring detection signals that depend on the magnetization in the region of action. The magnetization is influenced by the change in the position in space of the first and second sub-zones. A compensation controller provides a compensation signal to the drive signal chain and/or to the detection signal chain by a coupler.Type: GrantFiled: December 14, 2007Date of Patent: October 25, 2011Assignee: Koninklijke Philips Electronics N.V.Inventors: Bernhard Gleich, Juergen Weizenecker
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Patent number: 8044656Abstract: Device for calibration of a field transmitter comprising a shaped body on which there are disposed first means for sensing magnetic fields the activation of which allows calibration of a first measurement parameter of the transmitter, second means for sensing magnetic fields the activation of which allows calibration of a second measurement parameter of the transmitter, magnetic actuation means suitable to activate said first and second means for sensing magnetic fields. Said shaped body is configured so that it can be removably connected to the transmitter on the external surface of the enclosure thereof.Type: GrantFiled: March 19, 2007Date of Patent: October 25, 2011Assignee: ABB S.p.A.Inventors: Andrea Moroni, Alessandro Dell'Oro, Ronaldo Dos Santos
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Publication number: 20110248704Abstract: In general, the invention relates to an algorithm and process for automated and/or continuous calibration of magnetic sensor, for example such as a sensor installed in a mobile positioning system handset. According to certain aspects, the calibration process can use the normal motion of the handset such that all measurement data from the three orthogonal axes of sensor when exposed to Earth's magnetic field is collected. According to still further aspects, the process includes fitting measurement data to an ellipsoid that characterizes the actual magnetic field measurements from a magnetic sensor, so that anomalies such as hard iron effect, soft iron effect and scale factors can be extracted and/or corrected by comparison to a sphere represented by magnetic field data from a model at the sensor's location.Type: ApplicationFiled: April 9, 2010Publication date: October 13, 2011Inventors: Mahesh CHOWDHARY, Mahaveer Jain
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Publication number: 20110248658Abstract: The position of a rotor of a motor is determined. The motor includes the rotor and a stator and the stator includes a plurality of coils. The rotor further includes at least one rotating magnetic field device. When the rotor is moving below a threshold speed, the current in each of the plurality of coils of the stator is measured. A pre-programmed data structure is accessed. The pre-programmed data structure stores a plurality of stator currents associated with a plurality of predetermined rotor positions. A first absolute position of the rotor is determined from the data structure according to the measured current from each of the plurality of coils. When the rotor is moving above the threshold speed, one or more rising or falling edges of magnetic field strength associated with the at least one rotating magnetic field device of the rotor are sensed. At least one timing aspect of the rising and falling edges of magnetic field strength are compared to determine a second absolute position of the rotor.Type: ApplicationFiled: February 21, 2011Publication date: October 13, 2011Applicant: CONTINENTAL AUTOMOTIVE SYSTEMS, INC.Inventors: Patrick A. O'Gorman, Rene Vivanco, Alex Kurnia
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Publication number: 20110218940Abstract: A parking system uses a three-dimensional magnetic field sensor as part of a vehicle detector to monitor plural parking spaces. The detector is calibrated to detect the presence or absence of a vehicle in each of the monitored spaces. The status of each space is communicated to a central controller. A pay station communicates with a central controller when a parking interval has been purchased. The controller may warn customers when the interval is about to expire and law enforcement when it has expired.Type: ApplicationFiled: July 28, 2010Publication date: September 8, 2011Applicant: RECHARGE POWER LLCInventors: Gary Bergstrom, Joseph B. Seale, Nathaniel Tyler Smith
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Patent number: 7994781Abstract: Reference standards or articles having prescribed levels of damage are fabricated by monitoring an electrical property of the article material, mechanically loading the article, and removing the load when a change in electrical properties indicates a prescribed level of damage. The electrical property is measured with an electromagnetic sensor, such as a flexible eddy current sensor, attached to a material surface, which may be between layers of the article material. The damage may be in the form of a fatigue crack or a change in the mechanical stress underneath the sensor. The shape of the article material may be adjusted to concentrate the stress so that the damage initiates under the sensor. Examples adjustments to the article shape include the use of dogbone geometries with thin center sections, reinforcement ribs on the edges of the article, and radius cut-outs in the vicinity of the thin section.Type: GrantFiled: August 3, 2009Date of Patent: August 9, 2011Assignee: JENTEK Sensors, Inc.Inventors: Neil J. Goldfine, Darrell E. Schlicker, Karen E. Walrath, Andrew P. Washabaugh
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Patent number: 7994773Abstract: 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. A current source coupled to the magnetic field detection element provides a stimulating current for the magnetic field detection element that builds in a ramp-like progression. A microcontroller is in communication with the voltage signal wherein the microcontroller is configured to detect and control the ramping time of the magnetic field detection element and to sense after the ramping time the voltage signal from the magnetic field detection element. 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: GrantFiled: July 11, 2008Date of Patent: August 9, 2011Assignee: Data Security, Inc.Inventor: Robert A. Schultz
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Patent number: 7994776Abstract: A failure detection apparatus for a resolver outputting a sine signal indicative of sin ? and a cosine signal indicative of cos ? according to a rotational angle ? of a rotator, includes an inspection value calculating section configured to calculate an inspection value based on at least one of the sine signal and the cosine signal; a failure detecting section configured to judge whether the resolver is in a failure state or not on the basis of the inspection value; a counting section configured to gradually increase a count value with a lapse of time when the failure detecting section is determining that the resolver is in the failure state, and configured to gradually decrease the count value with a lapse of time when the failure detecting section is determining that the resolver is not in the failure state; and a failure deciding section configured to finally decide that the resolver has caused the failure on the basis of the count value.Type: GrantFiled: February 11, 2009Date of Patent: August 9, 2011Assignee: Hitachi, Ltd.Inventors: Tamotsu Yamaura, Kenichi Hamada, Yutaka Makino
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Publication number: 20110187350Abstract: An embodiment of a magnetic-field sensor has a plurality of sensor elements connected to form measurement arrangements, each measurement arrangement having a measurement tap, and a control circuit formed to perform an embodiment of a method of calibrating the magnetic-field sensor.Type: ApplicationFiled: April 13, 2011Publication date: August 4, 2011Applicant: INFINEON TECHNOLOGIES AGInventors: Udo Ausserlechner, Dirk Hammerschmidt
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Patent number: 7987583Abstract: A step portion for mounting a row bar is provided at a table stepping down from the face of the table, and by lowering a pair of hooks crossing over the step portion in its width direction, a row bar held by the hooks is mounted on the step portion. While interposing the row bar mounted on the step portion between a pair of hooks and a side face of the step portion, the side in longitudinal direction of the row bar and the bottom face thereof are butted to the bottom face and the standing up side face of the step portion to position two axes of the row bar among XYZ directions, successively, positioning of the row bar in one remaining direction along longitudinal direction of the row bar mounted on the step portion is performed by moving the table in the one remaining axial direction.Type: GrantFiled: March 20, 2008Date of Patent: August 2, 2011Assignee: Hitachi High-Technologies CorporationInventors: Teruaki Tokutomi, Yoshinori Kitano
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Patent number: 7940042Abstract: A method for testing an MR element includes a step of obtaining a ferromagnetic resonance frequency f0 of the MR element to be tested by applying an external magnetic field in a track-width direction to the MR element, a step of calculating a stiffness magnetic field Hstiff from the obtained ferromagnetic resonance frequency f0 using a predetermined formula, a step of obtaining a relationship of a stiffness magnetic field Hstiff with respect to an external magnetic field applied in the track-width direction from the applied external magnetic field and the calculated stiffness magnetic field Hstiff, a step of obtaining a uniaxial anisotropic magnetic field Hk of a free layer of the MR element from the obtained relationship of the stiffness magnetic field Hstiff with respect to the external magnetic field applied, and a step of judging whether the MR element is good product or not by comparing the obtained uniaxial anisotropic magnetic field Hk with a predetermined threshold.Type: GrantFiled: January 7, 2009Date of Patent: May 10, 2011Assignee: TDK CorporationInventor: Takumi Yanagisawa
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Patent number: 7919961Abstract: The invention relates to a method for measuring the magnetic permeability of a magnetic material by measuring the magnetic interaction of an electromagnetic field with this material by using a measuring device including a measuring cell connected through a microwave frequency cable (13) to a vector network analyser (12), said method comprising steps for gauging/calibrating said measuring device, for determining corrective coefficients to be applied to the measurements obtained by means of this device, for verifying the non-drift of this device, these steps being carried out with the help of a reference sample, wherein a reference sample is used, comprising at least one inclusion which enables creation, in a given volume, of a local artificial permeability, each inclusion being achieved by combining at least one inductive component possibly associated with a combination of at last one capacitive and/or resistive and/or active component, the frequency response of the electromagnetic properties of each volume beType: GrantFiled: October 20, 2006Date of Patent: April 5, 2011Assignee: Commissariat a l'Energie AtomiqueInventors: Marc Ledieu, Olivier Acher
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Patent number: 7915950Abstract: Systems and methods for providing bias currents to multiple analog circuits are disclosed. An integrated circuit comprises a calibration circuit which compares a high tolerance external component to a plurality of internal components manufactured to span the variability of the process, voltage and temperature. The best fitting internal component is communicated to bias circuits which can select an internal component from a local plurality of internal components with matching desired characteristics. In this manner, analog circuits can be locally biased with the tolerance usually associated with a high tolerance external reference component, without the necessity for a local external reference component.Type: GrantFiled: June 20, 2008Date of Patent: March 29, 2011Assignee: Conexant Systems, Inc.Inventors: Ray Rosik, Weinan Gao