Source: https://patents.google.com/patent/US7746056B2/en
Timestamp: 2019-02-17 16:59:32
Document Index: 336658960

Matched Legal Cases: ['art 1', 'art 2', 'art 1', 'art 2', 'art 3', 'art 4', 'art 5']

US7746056B2 - Integrated sensor - Google Patents
Integrated sensor Download PDF
US7746056B2
US7746056B2 US12/357,421 US35742109A US7746056B2 US 7746056 B2 US7746056 B2 US 7746056B2 US 35742109 A US35742109 A US 35742109A US 7746056 B2 US7746056 B2 US 7746056B2
US12/357,421
US20090128130A1 (en
Jason Stauth
2003-02-11 Priority to US10/364,442 priority Critical patent/US7259545B2/en
2007-06-25 Priority to US11/767,631 priority patent/US7518354B2/en
2009-01-22 Application filed by Allegro MicroSystems LLC filed Critical Allegro MicroSystems LLC
2009-01-22 Priority to US12/357,421 priority patent/US7746056B2/en
2009-01-22 Assigned to ALLEGRO MICROSYSTEMS, INC. reassignment ALLEGRO MICROSYSTEMS, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: DICKINSON, RICHARD, FORREST, GLENN, STAUTH, JASON, VIG, RAVI
2009-05-21 Publication of US20090128130A1 publication Critical patent/US20090128130A1/en
2010-06-29 Publication of US7746056B2 publication Critical patent/US7746056B2/en
An electronic circuit includes a substrate having a surface and a device supported by the surface of the substrate. The electronic circuit also includes a magnetic field transducer disposed over the surface of the substrate and an insulating layer disposed between the substrate and the magnetic field transducer. The electronic circuit also includes a conductor disposed over the magnetic field transducer. The conductor is configured to carry an electrical current to generate a first magnetic field. The electronic circuit is responsive to the first magnetic field.
This application is a Continuation Application of and claims the benefit of U.S. patent application Ser. No. 11/767,631 filed Jun. 25, 2007, now U.S. Pat. No. 7,518,354, which application is a Divisional Application of and claims the benefit of U.S. patent application Ser. No. 10/364,442 filed Feb. 1, 2003, now U.S. Pat. No. 7,259,545, issued Aug. 21, 2007, which applications and patents are incorporated herein by reference in their entirety.
This invention relates generally to electrical sensors and, more particularly, to a miniaturized integrated sensor having a magnetic field transducer and a conductor disposed on a substrate. The integrated sensor can be used to provide a current sensor, an isolator, or a magnetic field sensor.
As is known in the art, conventional current sensors can be arranged in either an open loop or a closed loop configuration. An “open loop” current sensor includes a magnetic field transducer in proximity to a current-carrying, or primary, conductor. The magnetic field transducer provides an output signal proportional to the magnetic field generated by current passing through the primary conductor.
A “closed loop” current sensor additionally includes a secondary conductor in proximity to the magnetic field transducer. A current is passed through the secondary conductor in order to generate a magnetic field that opposes and cancels the magnetic field generated by a current passing through the primary conductor. Thus, the magnetic field in the vicinity of the magnetic field transducer is substantially zero. The current passed through the secondary conductor is proportional to the magnetic field in the primary conductor and thus, to the primary current. The closed loop configuration generally provides improved accuracy over the open loop configuration. This is because hysteresis effects associated with the transducer are eliminated by maintaining the magnetic field on the transducer at approximately zero gauss. The closed loop configuration also generally provides improved linearity in comparison with the open loop configuration, as well as increased dynamic range. These improvements are further described below.
In accordance with one aspect of the present invention, an electronic circuit includes a substrate having a surface and a device supported by the surface of the substrate. The electronic circuit also includes a magnetic field transducer disposed over the surface of the substrate and an insulating layer disposed between the substrate and the magnetic field transducer. The electronic circuit also includes a conductor disposed over the magnetic field transducer. The conductor is configured to carry an electrical current to generate a first magnetic field. The electronic circuit is responsive to the first magnetic field.
Referring to FIG. 1, an electronic circuit 10 includes a silicon substrate 14, a magnetic field transducer 12 disposed over a surface 14 a of the silicon substrate, and a conductor 26 disposed over the surface 14 a of the silicon substrate proximate to the magnetic field transducer 12. With this arrangement, an integrated circuit is provided which is suitable for various applications, such as a current sensor (FIGS. 1, 1A, 3 and 4), a magnetic field sensor (FIGS. 6 and 6A), and a signal isolator (FIGS. 7 and 7A).
The magnetic field transducer 12 is polarized, so that the “direction” of its response to magnetic fields is dependent on the direction of the magnetic field along response axis 13. More particularly, the response, here resistance change, of the illustrative GMR device 12 changes in one direction when the magnetic field is in one direction along the response axis 13, and changes in the other direction when the magnetic field is in the other direction along the response axis 13. The magnetic field transducer 12 is polarized such that its resistance increases with an increase in the secondary current 24.
In operation, a primary current 110 flows through the first primary conductor portion 108 a, thereby generating a first primary magnetic field 112 a and a secondary current 116 flows through the first secondary conductor portion 114 a, thereby generating a first secondary magnetic field 115 a. Because the secondary current 116 passes through the secondary conductor portion 114 a in a direction opposite to the primary current 110 passing through the primary conductor portion 108 a, the first secondary magnetic field 115 a is opposite in direction to the first primary magnetic field 112 a. For similar reasons, a second secondary magnetic field 115 b is opposite in direction to a second primary magnetic field 112 b.
A voltage source 124 here integrated in the silicon substrate 104 provides a current through the first and second magnetic field transducers 102, 118 and therefore, generates a voltage at node 120 having a magnitude related to the magnetic field experienced by the magnetic field transducers 102, 118. An amplifier 122, coupled to the magnetic field transducers 102, 118, provides the secondary current 116 to the secondary conductor 114 in response to the voltage at the node 120.
In the particular arrangement shown, the node 120 is coupled to the negative input of the amplifier 122, and the resistance of the first magnetic field transducer 102 tends to decrease while the resistance of the second magnetic field transducer tends to increase in response to the first and second primary magnetic fields 112 a, 112 b. However, as described above, the first and second secondary magnetic fields 115 a, 115 b tend to oppose the first and second primary magnetic fields 112 a, 112 b.
With this arrangement, a reduction in the sensitivity of the electronic circuit 100 to external magnetic fields is achieved. This is because an external magnetic field would cause the resistance of the two magnetic field transducers 102, 118 to change in the same direction, therefore generating no voltage change at the node 120.
The first magnetic field transducer 102 is oriented on the silicon substrate 104 such that the response axis 103 is aligned with both the first primary magnetic field 112 a and the first secondary magnetic field 115 a. The magnetic field experienced by the first magnetic field transducer 102 is the sum of the first secondary magnetic field 115 a and first primary magnetic field 112 a along the response axis 103. Similarly, the magnetic field experienced by the second magnetic field transducer 118 is the sum of the second secondary magnetic field 115 b and second primary magnetic field 112 b along the response axis 119. Since the first secondary magnetic field 115 a is opposite in direction to the first primary magnetic field 112 a along the response axis 103, the first secondary magnetic field 115 a tends to cancel the first primary magnetic field 112 a. For similar reasons, the second secondary magnetic field 115 b tends to cancel the second primary magnetic field 112 b.
The amplifier 122 generates the secondary current 116 in proportion to the voltage at node 120 and therefore, the amplifier 122 provides the secondary current 116 at a level necessary to generate the first and second secondary magnetic fields 115 a, 115 b sufficient to cancel the first and second primary magnetic fields 112 a, 112 b respectively along the response axes 103, 119, so that the total magnetic field experienced by each of the magnetic field transducers 102, 118 is substantially zero gauss.
Referring now to FIG. 4, an electronic circuit 150 in the for of a closed loop current sensor is shown. The current sensor 150 differs from the current sensor 10 of FIG. 1 in that it contains four magnetic field transducers 152, 155, 165 and 168 arranged to further reduce errors, as will be described. The magnetic field transducers 152, 168, 155, 165 are disposed over a surface 154 a of a silicon substrate 154. A conductor 164 is also disposed over the surface 154 a of the silicon substrate 154 proximate to the magnetic field transducers 152, 168, 155, 165. A further, primary, conductor 158 is isolated from the silicon substrate 154 by a dielectric 156, as shown. The primary conductor 158 has a first primary conductor portion 158 a and a second primary conductor portion 158 b that together form a continuous primary conductor 158 through which a primary current 160 flows. Similarly, the secondary conductor 164 has first and second secondary conductor portions 164 a, 164 b.
Unless otherwise noted, components of FIG. 4 have the same structure, features, and characteristics as like components in preceding figures. For example, magnetic field transducers 152, 168, 155, 165 are shown here as magnetoresistance elements, such as giant magnetoresistance (GMR) elements.
In operation, a primary current 160 flows through the primary conductor 158, thereby generating a first primary magnetic field 162 a and a second primary magnetic field 162 b. A secondary current 166 flows through the second secondary conductor 164, thereby generating a first secondary field 165 a at the conductor portion 164 a and a second secondary magnetic field 165 b at conductor portion 164 b. Because the secondary current 166 passes through the first secondary conductor portion 164 a in a direction opposite to the primary current 160 passing through the first primary conductor portion 158 a, the first secondary magnetic field 165 a is opposite in direction to the first primary magnetic field 162 a. For similar reasons, the second secondary magnetic field 165 b is opposite in direction to the second primary magnetic field 162 b.
A first voltage source 174, here integrated in the silicon substrate 154, provides a current through the first and second magnetic field transducers 152, 168 and, therefore, generates a voltage at node 170 having a magnitude related to the magnetic field experienced by the first and second magnetic field transducers 152, 168. Similarly, a second voltage source 159, also here integrated in the silicon substrate 154, provides a current through the third and fourth magnetic field transducers 155, 165 and, therefore, generates a voltage at node 171 having a magnitude related to the magnetic field experienced by the third and fourth magnetic field transducers 155, 165. In one particular embodiment, the first and the second voltage sources 174, 159 supply the same voltage and are provided by a single voltage source. An amplifier 172, coupled to the magnetic field transducers 152, 168, 155, 165, provides the secondary current 166 to the secondary conductor 164 in response to the voltage difference between the nodes 170 and 171.
In the particular arrangement shown, the node 170 is coupled to a negative input of the amplifier 172 and the node 171 is coupled to a positive input of the amplifier 172. The voltage at the node 171 tends to increase while the voltage at the node 170 tends to decrease in response to the first and second primary magnetic fields 162 a, 162 b. However, as described above, the first and second secondary magnetic fields 165 a, 165 b tend to oppose the first and second primary magnetic fields 112 a, 112 b.
The first and third magnetic field transducers 152, 155 are oriented such that the response axes 153, 157 are aligned with the first primary magnetic field 162 a and with the first secondary magnetic field 165 a. The magnetic field experienced by the first magnetic field transducer 152 and the third magnetic field transducer 155 is the sum of the first secondary magnetic field 165 a and the first primary magnetic field 162 a along the respective response axes 153, 157. Similarly, the magnetic field experienced by the second magnetic field transducer 168 and the fourth magnetic field transducer 165 is the sum of the second secondary magnetic field 165 b and the second primary magnetic field 162 b along the respective response axes 169, 167. Since the first secondary magnetic field 165 a is opposite in direction to the first primary magnetic field 162 a along the response axes 153, 157, the first secondary magnetic field 165 a tends to cancel the first primary magnetic field 162 a. Similarly, since the second secondary magnetic field 165 b is opposite in direction to the second primary magnetic field 162 b along the response axes 167, 169, the second secondary magnetic field 165 b tends to cancel the second primary magnetic field 162 b. The amplifier 172 generates the secondary current 166 in proportion to the voltage difference between nodes 170 and 171.
In the particular arrangement shown, the node 220 is coupled to a negative input of the amplifier 222 and the node 221 is coupled to a positive input of the amplifier 222. The voltage at the node 221 tends to increase while the voltage at the node 220 tends to decrease in response to the external magnetic field 240. However, as described above, the first and second secondary magnetic fields 215 a, 215 b tend to oppose the first and second primary magnetic fields 112 a, 112 b.
The first, second, third, and fourth magnetic field transducers 202, 218, 205, 215 are oriented such that the response axes 203, 219, 207, 217 are aligned with the external magnetic field 240 and also with the first and second secondary magnetic fields 215 a, 215 b. The magnetic field experienced by the first and third magnetic field transducers 202, 205 is the sum of the first secondary magnetic field 215 a and the external magnetic field 240 along the response axes 203, 207 respectively. Similarly, the magnetic field experienced by the second and fourth magnetic field transducers 218, 215 is the sum of the second secondary magnetic field 215 b and the external magnetic field 240 along the response axes 219, 217 respectively. Since the first and second magnetic fields 215 a, 215 b are opposite in direction to the external magnetic field 240 along the response axes 203, 219, 207, 217, the first and second magnetic fields 215 a, 215 b tend to cancel the external magnetic field 240. The amplifier 221 generates the current 216 in proportion to the voltage difference between the node 220 and the node 221. Thus, the amplifier 222 provides the current 216 at a level necessary to generate the first and second magnetic fields 215 a, 215 b sufficient to cancel the external magnetic field 240 along the response axes 203, 219, 207, 217 so that the total magnetic field experienced by each of the magnetic field transducers 202, 218, 205, 215 is substantially zero gauss.
In operation, current 366 flows through a first portion 364 a of conductor 364 and through a second portion 364 b of conductor 364, thereby generating a first magnetic field 365 a and a second magnetic field 365 b. Because the current 366 passing through the first conductor portion 364 a is opposite in direction to the current 366 passing through the second conductor portion 364 b, the first magnetic field 365 a is opposite in direction to the second magnetic field 365 b.
A first voltage source 374, here integrated in the silicon substrate 354, provides a current through the first and second magnetic field transducers 352, 368 and, therefore, generates a voltage at node 370 having a magnitude related to the magnetic field experienced by the first and second magnetic field transducers 352, 368. Similarly, a second voltage source 359, also here integrated in the silicon substrate 354, provides a current through the third and fourth magnetic field transducers 355, 365 and therefore, generates a voltage at node 371 having a magnitude related to the magnetic field experienced by the third and fourth magnetic field transducers 355, 365. In one embodiment, the first and the second voltage sources 374, 359 supply the same voltage and are provided by a single voltage source. An amplifier 372, coupled to the magnetic field transducers 352, 368, 355, 365, provides a voltage output to a comparator 390, which provides a digital voltage, Vout, between output terminals 378, 380 in response to the voltage difference between the nodes 170 and 171.
The first and third magnetic field transducers 352, 355 are oriented on the silicon substrate 354 such that the response axes 353, 357 are aligned with the first magnetic field 365 a. The magnetic field experienced by the first and third magnetic field transducers 352, 355 is the first magnetic field 365 a. Similarly, the magnetic field experienced by the second and fourth magnetic field transducers 368, 365 is the second magnetic field 365 b.
With this arrangement, the digital output voltage, Vout, is responsive to the input voltage, Vin, and is electrically isolated therefrom. More particularly, the output voltage, Vout, has a logic state dependent on whether the sensed input voltage, Vin, is greater or less than a predetermined threshold voltage.
The width w1 of the two input leads 402 a, 402 b is selected in accordance with a variety of factors, including, but not limited to the current carried by the input leads. The width w2 of the leads 404 a-404 d is also selected in accordance with a variety of factors including, but not limited to the current carried by the leads 404 a-404 d.
The integrated circuit body 406 can be comprised of plastic or any conventional integrated circuit body material. The illustrated integrated circuit 400 is but one example of packaging that can be used with the integrated sensors of the present invention. However, the packaging is not limited to any particular package type. For example, the package can be one or more of a conventional SOIC8, SOIC16, or an MLP package.
A current 557, corresponding to the secondary current 166 (FIG. 4) passes through the conductor 556, corresponding to secondary conductor 164 (FIG. 4). Four conductor portions 556 a-556 d are in proximity to the first and the third magnetic field transducers 552, 554 respectively such that the current 557 passes by the first and third magnetic field transducers 552, 554 in a direction that generates four magnetic fields 558 a-558 d in the same direction. Another four conductor sections 556 e-556 h are in proximity to the second and fourth magnetic field transducers 553, 555 such that the current 557 passes by the second and fourth magnetic field transducers 553, 555 in a direction that generates four magnetic fields 558 e-558 h in a direction opposite to the magnetic fields 558 a-558 d.
The four magnetic fields 558 a-558 d are concentrated by first and second flux concentrators 560 a, 560 b and the other four magnetic fields 558 e-558 h are concentrated by third and fourth flux concentrators 560 c, 560 d. The first and second flux concentrators 560 a, 560 b operate to concentrate the magnetic fields 558 a-558 d in the vicinity of the first and third magnetic field transducers 552, 554. Similarly, the third and fourth flux concentrators 560 c, 560 d operate to concentrate the magnetic fields 558 e-558 h in the vicinity of the second and fourth magnetic field transducers 553, 555. The four flux concentrators 560 a-560 d can be comprised of any magnetically permeable material including, but not limited to, ferrite, permalloy, and iron alloys. The four flux concentrators 560 a-560 d, can be fabricated in a variety of ways, including but not limited to, deposition, sputtering, and electroplating techniques.
US12/357,421 2003-02-11 2009-01-22 Integrated sensor Active US7746056B2 (en)
US10/364,442 US7259545B2 (en) 2003-02-11 2003-02-11 Integrated sensor
US11/767,631 US7518354B2 (en) 2003-02-11 2007-06-25 Multi-substrate integrated sensor
US12/357,421 US7746056B2 (en) 2003-02-11 2009-01-22 Integrated sensor
US11/767,631 Continuation US7518354B2 (en) 2003-02-11 2007-06-25 Multi-substrate integrated sensor
US20090128130A1 US20090128130A1 (en) 2009-05-21
US7746056B2 true US7746056B2 (en) 2010-06-29
ID=32824435
US10/364,442 Active 2023-11-24 US7259545B2 (en) 2003-02-11 2003-02-11 Integrated sensor
US11/767,631 Active US7518354B2 (en) 2003-02-11 2007-06-25 Multi-substrate integrated sensor
US12/357,421 Active US7746056B2 (en) 2003-02-11 2009-01-22 Integrated sensor
US (3) US7259545B2 (en)
EP (6) EP2431756A3 (en)
JP (1) JP2006514283A (en)
AU (1) AU2003287232A1 (en)
WO (1) WO2004072672A1 (en)
US9000761B2 (en) 2012-01-19 2015-04-07 Avago Technologies General Ip (Singapore) Pte. Ltd. Hall-effect sensor isolator
US9958482B1 (en) 2016-12-20 2018-05-01 Allegro Microsystems, Llc Systems and methods for a high isolation current sensor
US10036785B2 (en) 2016-07-18 2018-07-31 Allegro Microsystems, Llc Temperature-compensated magneto-resistive sensor
EP3364208A1 (en) * 2017-02-17 2018-08-22 Allegro MicroSystems, LLC Current sensor system
FR2863364B1 (en) * 2003-12-08 2006-03-03 Abb Entrelec Sas Current sensor has reduced sensitivity to magnetic interference fields
EP1548702A1 (en) * 2003-12-24 2005-06-29 Interuniversitair Microelektronica Centrum Vzw Method for ultra-fast controlling of a magnetic cell and related devices
FR2870351B1 (en) * 2004-05-14 2006-07-14 Alstom Transport Sa Device for measuring an electromagnetic field control system using this device and electronic circuit designed for this device
TW200630632A (en) * 2004-10-11 2006-09-01 Koninkl Philips Electronics Nv Non-linear magnetic field sensors and current sensors
JP4131869B2 (en) * 2005-01-31 2008-08-13 Ｔｄｋ株式会社 Current sensor
DE102006021774B4 (en) * 2005-06-23 2014-04-03 Siemens Aktiengesellschaft Current sensor for galvanically isolated current measurement
JP4415923B2 (en) 2005-09-30 2010-02-17 Ｔｄｋ株式会社 Current sensor
EP1772737A3 (en) * 2005-10-08 2008-02-20 Melexis Technologies SA Assembly group for the current measurement
JP2007147460A (en) * 2005-11-28 2007-06-14 Denso Corp Magnetic balance type electric current sensor
JP2007218700A (en) * 2006-02-15 2007-08-30 Tdk Corp Magnetometric sensor and current sensor
DE102006026148A1 (en) * 2006-06-06 2007-12-13 Insta Elektro Gmbh Electrical / electronic device
EP1882953A1 (en) * 2006-07-26 2008-01-30 Siemens Aktiengesellschaft Current measuring device
DE102006052748A1 (en) * 2006-08-14 2008-04-30 Rohde & Schwarz Gmbh & Co. Kg Oscilloscope probe
JP2008151530A (en) * 2006-12-14 2008-07-03 Denso Corp Semiconductor integrated circuit for detecting magnetic field
FR2910162B1 (en) * 2006-12-18 2009-12-11 Schneider Electric Ind Sas measuring signal coupling device has electrical insulation and electrical apparatus comprising such a device
GB2446146B (en) 2007-01-31 2009-11-18 Gm Global Tech Operations Inc Arrangement of a two stage turbocharger system for an internal combustion engine
JP4853807B2 (en) * 2007-02-21 2012-01-11 甲神電機株式会社 Current sensing device
JP4893506B2 (en) * 2007-06-04 2012-03-07 甲神電機株式会社 Current sensor
DE102007040399B4 (en) * 2007-08-27 2012-05-03 Siemens Ag An apparatus for galvanically isolated measurement of the electrical power consumption of a dipole
MD4002C2 (en) * 2008-03-19 2010-07-31 Институт Электронной Инженерии И Промышленных Технологий Академии Наук Молдовы Apparatus for measuring the intensity of the magnetic field
US8203337B2 (en) * 2009-06-15 2012-06-19 Headway Technologies, Inc. Elimination of errors due to aging in magneto-resistive devices
US8248063B2 (en) * 2009-08-17 2012-08-21 Headway Technologies, Inc. Open loop magneto-resistive magnetic field sensor
US8395383B2 (en) * 2010-03-11 2013-03-12 Alps Green Devices Co., Ltd. Current sensor including magnetic detecting element
JP5012939B2 (en) * 2010-03-18 2012-08-29 Ｔｄｋ株式会社 Current sensor
US8994370B2 (en) 2010-07-30 2015-03-31 Peugeot Citroën Automobiles SA Magnetoresistor integrated sensor for measuring voltage or current, and diagnostic system
FR2963432B1 (en) * 2010-07-30 2013-02-15 Commissariat Energie Atomique Sensor integrated voltage measurement or current has basic magnetoresistors
US8638092B2 (en) 2010-08-06 2014-01-28 Honeywell International, Inc. Current sensor
CH703903B1 (en) * 2010-10-01 2014-04-30 Melexis Tessenderlo Nv Current sensor.
JP5794777B2 (en) * 2010-12-22 2015-10-14 三菱電機株式会社 Semiconductor device
JP5482736B2 (en) * 2011-06-28 2014-05-07 株式会社デンソー Current sensor
JP2013047610A (en) * 2011-08-28 2013-03-07 Denso Corp Magnetic balance type current sensor
JP2013055281A (en) * 2011-09-06 2013-03-21 Alps Green Devices Co Ltd Current sensor
US9812588B2 (en) * 2012-03-20 2017-11-07 Allegro Microsystems, Llc Magnetic field sensor integrated circuit with integral ferromagnetic material
CN102692609B (en) * 2012-05-30 2014-09-10 电子科技大学 Minitype magnetic field sensor based on nano particle magneto rheological elastomer film
US9817036B2 (en) 2012-11-06 2017-11-14 Nxp Usa, Inc. High bandwidth current sensor and method therefor
DE102012024062A1 (en) * 2012-12-10 2014-06-12 Micronas Gmbh magnetic field sensor
JP2014202737A (en) * 2013-04-03 2014-10-27 甲神電機株式会社 Current sensor
TWI504904B (en) * 2013-07-30 2015-10-21 Asahi Kasei Microdevices Corp
JP6099588B2 (en) * 2014-03-20 2017-03-22 三菱電機株式会社 Magnetically coupled isolator
JP6457243B2 (en) * 2014-11-06 2019-01-23 株式会社東芝 Current sensors, and smart meters
JP6278909B2 (en) * 2015-02-03 2018-02-14 アルプス電気株式会社 Current sensor
US4343026A (en) 1980-07-09 1982-08-03 Spin Physics, Inc. Magnetoresistive head employing field feedback
US4385273A (en) 1979-11-27 1983-05-24 Lgz Landis & Gyr Zug Ag Transducer for measuring a current-generated magnetic field
US4691259A (en) 1984-08-27 1987-09-01 Sony Corporation Magnetic transducer head utilizing magnetoresistance effect
US4922606A (en) 1987-10-30 1990-05-08 Honeywell Inc. Method of making a current sensor
US4926116A (en) 1988-10-31 1990-05-15 Westinghouse Electric Corp. Wide band large dynamic range current sensor and method of current detection using same
US4937521A (en) 1987-07-07 1990-06-26 Nippondenso Co., Ltd. Current detecting device using ferromagnetic magnetoresistance element
US4939448A (en) 1987-10-16 1990-07-03 Liaisons Electroniques-Mecaniques Lem Sa Electric current sensing device of the magnetic field compensationtype
EP0539081A1 (en) 1991-10-22 1993-04-28 Hitachi, Ltd. Current sensor system or a method for current detection
US5218279A (en) * 1990-01-08 1993-06-08 Hitachi, Ltd. Method and apparatus for detection of physical quantities, servomotor system utilizing the method and apparatus and power steering apparatus using the servomotor system
DE4212737C1 (en) 1992-04-16 1993-07-08 Leica Mikroskopie Und Systeme Gmbh Compact bridge-connected sensor - has thin-film resistors on substrate
US5227721A (en) 1987-12-25 1993-07-13 Sharp Kabushiki Kaisha Superconductive magnetic sensor having self induced magnetic biasing
US5500590A (en) 1994-07-20 1996-03-19 Honeywell Inc. Apparatus for sensing magnetic fields using a coupled film magnetoresistive transducer
EP0710850A2 (en) 1994-11-04 1996-05-08 International Business Machines Corporation Magnetic field sensor and method for its manufacture
US5621377A (en) 1993-01-13 1997-04-15 Lust Electronic-Systeme Gmbh Sensor assembly for measuring current as a function of magnetic field gradient
US5719494A (en) 1994-10-15 1998-02-17 Lust Antriebstechnik Gmbh Sensor assembly
DE19650078A1 (en) 1996-12-03 1998-06-04 Inst Mikrostrukturtechnologie Sensor element for determining magnetic field or current
US5896030A (en) 1996-10-09 1999-04-20 Honeywell Inc. Magnetic sensor with components attached to transparent plate for laser trimming during calibration
US5896303A (en) 1996-10-11 1999-04-20 International Business Machines Corporation Discretization technique for multi-dimensional semiconductor device simulation
US6100686A (en) 1997-06-13 2000-08-08 U.S. Philips Corporation Magnetic field sensor with double wheatstone bridge having magneto-resistive elements
US6175296B1 (en) 1998-07-17 2001-01-16 Alps Electric Co., Ltd. Potentiometer provided with giant magnetoresistive effect elements
US6315875B1 (en) 1999-09-16 2001-11-13 Tdk Corporation Method of manufacturing thin-film magnetic head and method of manufacturing magnetoresistive device
US6329818B1 (en) 1998-07-17 2001-12-11 Alps Electric Co., Ltd. Magnetic field sensor having giant magnetoresistive effect elements, manufacturing method and apparatus therefor
US6392852B1 (en) 1999-04-27 2002-05-21 Tdk Corporation Thin-film magnetic head and method of manufacturing same, and magnetoresistive device
US20020093332A1 (en) 2001-01-18 2002-07-18 Thaddeus Schroeder Magnetic field sensor with tailored magnetic response
US6426620B1 (en) 1998-05-13 2002-07-30 Mitsubishi Denki Kabushiki Kaisha Magnetic field sensing element and device having magnetoresistance element and integrated circuit formed on the same substrate
US6459255B1 (en) 1999-09-02 2002-10-01 Yazaki Corporation Current detector
US20020180433A1 (en) 2001-06-01 2002-12-05 Koninklijke Philips Electronics N.V. Method of orienting an axis of magnetization of a first magnetic element with respect to a second magnetic element, semimanufacture for obtaining a sensor, sensor for measuring a magnetic field
US6501678B1 (en) 1999-06-18 2002-12-31 Koninklijke Philips Electronics N.V. Magnetic systems with irreversible characteristics and a method of manufacturing and repairing and operating such systems
WO2003019216A1 (en) 2001-08-27 2003-03-06 International Rectifier Corporation Magnetoresistive magnetic field sensors and motor control devices using same
US6591481B2 (en) 2001-04-25 2003-07-15 Tdk Corporation Method of manufacturing magnetoresistive device and method of manufacturing thin-film magnetic head
US20030151406A1 (en) 2002-02-11 2003-08-14 Hong Wan Magnetic field sensor
US6657826B2 (en) 2001-04-25 2003-12-02 Tdk Corporation Magnetoresistive device and method of manufacturing same, thin-film magnetic head and method of manufacturing same, head gimbal assembly and hard disk drive
US20040023064A1 (en) 2000-06-09 2004-02-05 Arno Ehresmann Wheatstone bridge containing bridge elements, consisting of a spin-valve system and a method for producing the same
US6721140B2 (en) 2000-11-22 2004-04-13 Tdk Corporation Magnetoresistive device and method of manufacturing same and thin-film magnetic head and method of manufacturing same
US6769166B1 (en) 1999-02-25 2004-08-03 Liaisons Electroniques-Mecaniques Lem Sa Method of making an electrical current sensor
WO2006044031A1 (en) 2004-10-12 2006-04-27 Allegro Microsystems, Inc. Resistor having a predetermined temperature coefficient
JPS57187671A (en) 1981-05-15 1982-11-18 Nec Corp Magnetism sensor
JPH02238372A (en) 1989-03-13 1990-09-20 Fujitsu Ltd Current detector
JPH0486723A (en) * 1990-07-31 1992-03-19 Toshiba Corp Polyhedral mirror and production thereof
US5402064A (en) * 1992-09-02 1995-03-28 Santa Barbara Research Center Magnetoresistive sensor circuit with high output voltage swing and temperature compensation
JPH10293141A (en) * 1997-04-18 1998-11-04 Yasusuke Yamamoto Current sensor
US6300614B1 (en) * 1998-03-30 2001-10-09 Jiri Joseph Petlan Communication system using gravitational waves
EP1636810A1 (en) 2003-06-11 2006-03-22 Philips Electronics N.V. Method of manufacturing a device with a magnetic layer-structure
2003-02-11 US US10/364,442 patent/US7259545B2/en active Active
2003-10-20 EP EP11192122.7A patent/EP2431756A3/en active Pending
2003-10-20 EP EP11192124.3A patent/EP2431757A3/en active Pending
2003-10-20 EP EP11192118.5A patent/EP2431755A3/en active Pending
2003-10-20 AU AU2003287232A patent/AU2003287232A1/en not_active Abandoned
2003-10-20 WO PCT/US2003/034141 patent/WO2004072672A1/en active Application Filing
2003-10-20 EP EP03781413A patent/EP1581817A1/en active Pending
2003-10-20 JP JP2004568309A patent/JP2006514283A/en active Pending
2003-10-20 EP EP11192127.6A patent/EP2431758A3/en active Pending
2003-10-20 EP EP11192131.8A patent/EP2431759A3/en active Pending
2007-06-25 US US11/767,631 patent/US7518354B2/en active Active
2009-01-22 US US12/357,421 patent/US7746056B2/en active Active
EP0710850A3 (en) 1994-11-04 1997-07-30 Ibm Magnetic field sensor and method for its manufacture
EP1225453A2 (en) 2001-01-18 2002-07-24 Delphi Technologies, Inc. Magnetic field sensor with tailored magnetic response
WO2007087121A3 (en) 2006-01-20 2008-04-03 Allegro Microsystems Inc Arrangements for an integrated sensor
WO2007087121A2 (en) 2006-01-20 2007-08-02 Allegro Microsystems, Inc. Arrangements for an integrated sensor
*"Utilization of GMR Materials;" NVE Corporation' Oct. 1, 1996; pp. 1-3.
Data Sheet; "High-Speed Digital Isolators, AduM1100AR/AduM1100BR;" as published by Analog Devices, Inc.; 2001, pp. 1-12.
Hirota, et al.; "Giant Magneto-Resistance Devices;" Springer Series in Surface Sciences, Apr. 7, 2002; pp. 11-17 and 71-77.
Image File Wrapper downloaded from PAIR for U.S. Appl. No. 10/962,889, on Mar. 10, 2008, filed Oct. 12, 2004; file through Mar. 10, 2009, 246 pages.
Image File Wrapper downloaded from PAIR on Mar. 10, 2009, for U.S. Appl. No. 11/335,944, filed Jan. 20, 2006; 199 pages.
Image File Wrapper downloaded from PAIR on Mar. 10, 2009. for U.S. Appl. No. 10/364,442, filed Feb. 11, 2003 U.S. Patent No. 7,259,545, issued Aug. 21, 2007; Part 1 of 2; 296 pages.
Image File Wrapper downloaded from PAIR on Mar. 10, 2009. for U.S. Appl. No. 10/364,442, filed Feb. 11, 2003 U.S. Patent No. 7,259,545, issued Aug. 21, 2007; Part 2 of 2; 299 pages.
Image File Wrapper downloaded from PAIR on May 20, 2009. for U.S. Appl. No. 11/767,631, filed Jun. 25, 2007; U.S. Patent No. 7,518,354, issued Apr. 14, 2009; Part 1 of 5; 271 pages.
Image File Wrapper downloaded from PAIR on May 20, 2009. for U.S. Appl. No. 11/767,631, filed Jun. 25, 2007; U.S. Patent No. 7,518,354, issued Apr. 14, 2009; Part 2 of 5; 266 pages.
Image File Wrapper downloaded from PAIR on May 20, 2009. for U.S. Appl. No. 11/767,631, filed Jun. 25, 2007; U.S. Patent No. 7,518,354, issued Apr. 14, 2009; Part 3 of 5; 270 pages.
Image File Wrapper downloaded from PAIR on May 20, 2009. for U.S. Appl. No. 11/767,631, filed Jun. 25, 2007; U.S. Patent No. 7,518,354, issued Apr. 14, 2009; Part 4 of 5; 278 pages.
Image File Wrapper downloaded from PAIR on May 20, 2009. for U.S. Appl. No. 11/767,631, filed Jun. 25, 2007; U.S. Patent No. 7,518,354, issued Apr. 14, 2009; Part 5 of 5; 233 pages.
Office Action dated Apr. 25, 2008 for European Appl. No. 05794713.7, 7 pages.
Office Action dated Apr. 6, 2009 for U.S. Appl. No. 11/335,944, filed Jan. 20, 2006; 19 pages.
Office Action dated Mar. 23, 2009 for Japanese Appl. No. 2004-568309 filed Aug. 11, 2005.
Office Action dated May 26, 2008 for Japanese Appl. No. 2004-568309 filed Aug. 11, 2005.
Partin et al.; "Temperature Stable Hall Effect Sensors;" IEEESensors Journal, vol. 6, No. 1; Feb. 2006; pp. 106-110.
PCT International Preliminary Examination Report of the ISA for PCT/US2007/000093 dated Aug. 9, 2008.
PCT Invitation to Pay Additional Fees; PCT Application No. PCT/US03/34141 dated Apr. 23, 2004; 7 pages.
PCT Search Report and Written Opinion of the ISA for PCT/US2005/029982 dated Jan. 18, 2006; 13 pages.
PCT Search Report and Written Opinion of the ISA for PCT/US2007/000093 dated Feb. 4, 2008; 14 pages.
PCT Search Report; PCT Application No. PCT/US03/34141 dated Jun. 17, 2004; 10 pages.
Pernia et al.; "Characteristics and Design of a Current Sensor Using Multilayer Co/Ni Structures;" IEEE, 1998 pp. 414-419.
Pernia, et al.; "Characteristics and Design of a Current Sensor Using Multilayer Co/Ni Structures;" 13th Annual Applied Power Electronics Conference and Exposition; Feb. 15-19, 1998; vol. 1; pp. 414-419.
Response to Offce Aciton dated May 26, 2008 for Japanese Appl. No. 2004-568309 filed Aug. 11, 2005.
Response to Office Action dated Apr. 6, 2009 for U.S. Appl. No. 11/335,944, filed Jan. 20, 2006; 17 pages.
Takenaga et al.; "High-Temperture Operations of Rotation Angle Sensors with Spin-Valve-Type Magnetic Tunnel Junctions;" IEEE Transactions on Magnetics; vol. 41, No. 10; Oct. 2005; pp. 3628-3630.
Takenaga et al.; "High-Temperture Operations of Rotation Angle Sensors with Spin—Valve—Type Magnetic Tunnel Junctions;" IEEE Transactions on Magnetics; vol. 41, No. 10; Oct. 2005; pp. 3628-3630.
Taylor et al.; "A Spin-Valve Based SOIC8 Current Sensor;" Allegro Microsystems, Inc. internal document; Aug. 17, 2006.
Taylor et al.; "A Spin—Valve Based SOIC8 Current Sensor;" Allegro Microsystems, Inc. internal document; Aug. 17, 2006.
US7816905B2 (en) * 2008-06-02 2010-10-19 Allegro Microsystems, Inc. Arrangements for a current sensing circuit and integrated current sensor
US20180262297A1 (en) * 2017-03-08 2018-09-13 Allegro Microsystems, Llc Methods and apparatus for communication over an isolation barrier with monitoring
US10142052B2 (en) * 2017-03-08 2018-11-27 Allegro Microsystems, Llc Methods and apparatus for communication over an isolation barrier with monitoring
WO2004072672A1 (en) 2004-08-26
US7259545B2 (en) 2007-08-21
EP2431756A3 (en) 2017-11-29
EP2431758A2 (en) 2012-03-21
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EP2431759A3 (en) 2017-11-15
US20070247146A1 (en) 2007-10-25
JP2006514283A (en) 2006-04-27
EP2431758A3 (en) 2017-11-22
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US20090128130A1 (en) 2009-05-21
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US20040155644A1 (en) 2004-08-12
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AU2003287232A1 (en) 2004-09-06
US7518354B2 (en) 2009-04-14
US5617071A (en) 1997-04-01 Magnetoresistive structure comprising ferromagnetic thin films and intermediate alloy layer having magnetic concentrator and shielding permeable masses
US7265531B2 (en) 2007-09-04 Integrated current sensor
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