WO2005085892A1 - Magnetfeldsensor und verfahren zu seinem betrieb - Google Patents
Magnetfeldsensor und verfahren zu seinem betrieb Download PDFInfo
- Publication number
- WO2005085892A1 WO2005085892A1 PCT/EP2005/000176 EP2005000176W WO2005085892A1 WO 2005085892 A1 WO2005085892 A1 WO 2005085892A1 EP 2005000176 W EP2005000176 W EP 2005000176W WO 2005085892 A1 WO2005085892 A1 WO 2005085892A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- signal
- sensor
- magnetic field
- output signal
- field sensor
- Prior art date
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
- G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
- G01R33/07—Hall effect devices
Definitions
- the invention relates to a magnetic field sensor with a sensor arrangement that is supplied by a supply device and generates a sensor signal, and with an evaluation device that is supplied with the sensor signal and that outputs an output signal.
- the invention further relates to a method for operating the magnetic field sensor.
- Such a magnetic field sensor known from EP 0525235 B1
- the * corresponding elements are implemented together in an integrated circuit.
- Hall elements are typical sensor elements with which a magnetic field sensor can be built up and which mostly cooperate in an array or a Hall element arrangement.
- a Hall element emits a voltage signal in the magnetic field as a Hall signal when a current flows through it perpendicular to the magnetic field.
- the Hall signal ie the Hall voltage, depends on the product of the vertical Component of the magnetic flux density, the Hall current and the Hall constant.
- the Hall constant which indicates the sensitivity of the Hall element, depends on the material.
- noise voltage which is composed of noise components of the Hall element and the subsequent evaluation device.
- noise components can be given by a temperature and material dependency.
- EP 0916074 B1 specifies a magnetic rotation sensor in which a magnet mounted on an axis is arranged above a Hall element array.
- the Hall element arrangement itself consists of a number of individual sensor elements which are in a specific geometric arrangement to one another.
- the evaluation device connected downstream of the Hall element array determines the angle of rotation of the axis from the Hall signal of the Hall element.
- Different temperature responses of the magnet and the Hall element as well as different distances between these two elements in particular influence the useful signal. This changes the distance between the useful signal and the noise signal.
- the invention is based on the object of specifying a magnetic field sensor and a method for its operation which result in better behavior of the magnetic field sensor.
- the invention is based on the idea of processing the sensor signal or the output signal of the evaluation device of the magnetic field sensor and using a feedback device to generate a control signal with which the size of the supply current or the supply voltage can be changed.
- the amplitude of the sensor signal is preferably determined and the supply current or the supply voltage of the sensor arrangement is set in a closed control loop so that the amplitude of the sensor signal remains constant.
- an output signal of the magnetic field sensor can be generated which has an optimized signal-to-noise ratio.
- the analog-to-digital converter (ADC) required for digital further processing of the sensor signal can have a smaller bit width than would be necessary without the control.
- the ADC can thus be constructed more simply and more cost-effectively. It is particularly advantageous if the output signal of the evaluation device corresponds to the amplitude of the sensor signal and this is determined by a comparison with an amplitude setpoint. The supply current or the supply voltage is then with the
- Amplification device set so that the amplitude of the sensor signal remains constant.
- the individual elements of the Hall element arrangement are preferably arranged in such a way that they generate two measurement signals which are phase-shifted by 90 °, in particular the Hall elements are arranged offset from one another by 90 °.
- the amplitude of the Hall signal can then be determined in a simple manner. If the two phase-shifted measurement signals are sinusoidal, the amplitude can be generated by squaring each measurement signal and then adding the squared signals.
- the measurement signals of the sensor arrangement are digitized and further processed in a computing device.
- the computing device generates the desired output signal, for example the angle of rotation, and on the other hand the amplitude information for the sensor signal.
- the feedback device contains a comparator that compares the amplitude signal of the magnetic field sensor with a reference value, that the comparator is followed by a counter that counts up or down depending on the output signal of the comparator and that the value of the counter is converted with a digital-to-analog converter (DAC) into a control signal for the supply current or the supply voltage.
- DAC digital-to-analog converter
- the supply current or the supply voltage is composed of a DC component and a controllable component, e.g. composed of a direct current from a constant current source and the current from a controlled current source, the controlled component being controlled by the feedback or amplification device.
- a controllable component e.g. composed of a direct current from a constant current source and the current from a controlled current source, the controlled component being controlled by the feedback or amplification device.
- control signals for the counter provided in the feedback branch are used and processed as status information.
- the status of the control device in particular the increase or decrease in the control information of the controlled component and thus the amplitude of the sensor signal or an overflow of the counter and thus an exit from the control range of the magnetic field sensor, can be determined.
- dynamic detection of a “push button” function can also be used, regardless of the absolute value.
- the invention is based on
- FIG. 1 shows a schematic structure of a magnetic field sensor with a Hall element arrangement
- FIG. 2 is a more detailed schematic representation of the reinforcement device
- Figure 3 is a schematic arrangement of a rotating field sensor.
- a magnetic field sensor H in particular a Hall element arrangement, is provided, which preferably consists of several sensor elements SE. Four sensor elements are preferably combined to form a sensor arrangement.
- the Hall elements of the sensor H are supplied individually by a supply device or, in the exemplary embodiment, are fed by a current source which contains a fixed current source FS and a controlled current source GS.
- the fixed current source FS generates a fixed operating current for the Hall elements of the magnetic field sensor H with a voltage and current supply device of the magnetic field sensor, not shown.
- the controlled current source GS generates the controlled current determined by the feedback branch. Both partial currents form the Hall current IH.
- the two Hall sensor arrangements are aligned in such a way that the measurement signals they generate are out of phase with each other by 90 °.
- the first measurement signal has a sinusoidal profile
- the second measurement signal has a cosine profile.
- both measurement signals reach the analog-digital converter ADC. This carries out the analog-to-digital conversion, for example with the aid of a sigma-delta modulator, so that, after digital filtering, which may still be provided, a digitized sine and a digitized cosine signal are available at the output of the ADC. Both signals are then linked and processed in the computing device R.
- the computing device R executes an algorithm with the digitized signals, so that the desired output signal or outputs are available at the output of the computing device.
- the angle W is thus available and is fed to an interface IF, which provides the signal output to external connections or carries out further processing of the digital angle signal W.
- the actual value amplitude AI of the Hall signal from the two measurement signals is available as another output signal of the computing device.
- the computing device R is usually designed as a digital signal processor (DSP).
- DSP digital signal processor
- CORDIC Coordinat Rotational Digital Computer
- a possible algorithm is described in "IEEE Transactions on Circuits and Systems - II: Analog and Digital Signal Processing", Vol. 48, No. 6, June 2001, PP 548 to 561. Of course, such a CORDIC can also execute other algorithms.
- another measurement variable to be recorded by the magnetic field sensor it is also possible to use the digital processor to execute a different algorithm in the DSP.
- the actual value amplitude AI of the Hall signal is now fed in a feedback loop to a feedback device RV, which outputs a control signal at its output for controlling the controlled current source GS.
- the feedback device is one in FIG.
- Amplification device and can also be referred to as AGC (Automatic Gain Control).
- a reference signal AS for the amplitude of the Hall signal is fed to the feedback device RV at a second input.
- the amplification device contains a digital comparator K, a counter Z and a digital-to-analog converter DAC.
- the actual values of the amplitude AI and the target values of the amplitude AS of the Hall signal are fed to the digital comparator.
- the setpoint AS preferably corresponds to an optimal amplitude at the input of the ADC.
- the digital comparator K generates an output signal from its two input signals AI and AS, which is fed to a counter Z.
- the counter Z is designed as an up / down counter. The value of the counter results for example by counting a clock frequency.
- two output signals U and D of the comparator K are provided at connections of the same name, of which output U is activated when the counter Z is to count up, while the output D is activated when the counter Z is to count down.
- the counter value is fed to the digital / analog converter DAC, which converts the counter value into an analog signal, which in turn controls the controlled current source GS (not shown in more detail).
- the controlled current source can moreover be designed in a manner known from the prior art.
- the output of the digital comparator K is routed separately to the terminals U and D parallel to the counter.
- the control signals U and D for the counter Z can be used as status information for the magnetic field sensor. For example, if the distance between the magnet and the Hall sensor changes, it is necessary to readjust the Hall current using the control loop described.
- the regulation of the control loop closed with the feedback device RV improves the noise behavior of the magnetic field sensor.
- this readjustment of the control loop can be displayed, because one signal U is characteristic for the upward counting and the other signal D for the downward counting. This makes it easy to determine externally whether the distance between the magnet and the Hall element has changed and in which direction it has changed. It is also possible to activate both signals U or D to indicate a counter overflow above the upper permissible value or below the lower permissible value, which means that the control range is exited
- the elements of the magnetic field sensor can be optimally adapted to the given conditions of use. It is thus possible to reduce the bit width of the ADC by one or even two bits compared to an unregulated embodiment. As a result, these elements can be implemented in a less complex and therefore more cost-effective manner.
- FIG. 3 shows, by way of illustration, the rotary sensor arrangement known from EP 0916074 B1.
- a magnet is mounted on a rotation axis DA above a Hall element H with a subsequent evaluation circuit.
- the invention now enables improved measurement and evaluation, which has a largely independent signal-to-noise ratio compared to changes in distance between the magnet and the Hall element arrangement.
- signal changes based on a Hall element-magnet ratio tilted from the vertical or a non-centric Hall element-magnet relationship can also be at least partially compensated for and thus enable a better useful signal.
- the invention is not limited to Hall arrangements, but that the idea of the regulated sensor arrangement can also be realized with other sensors that are based on other physical principles.
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- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Measuring Magnetic Variables (AREA)
- Transmission And Conversion Of Sensor Element Output (AREA)
- Hall/Mr Elements (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2007501133A JP2007525679A (ja) | 2004-03-02 | 2005-01-11 | 磁界センサ |
US10/591,976 US7825657B2 (en) | 2004-03-02 | 2005-01-11 | Magnetic field sensor and method for the operation thereof |
EP05700809A EP1721183B9 (de) | 2004-03-02 | 2005-01-11 | Magnetfeldsensor und verfahren zu seinem betrieb |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE102004010613.4 | 2004-03-02 | ||
DE102004010613.4A DE102004010613B4 (de) | 2004-03-02 | 2004-03-02 | Magnetfeldsensor und Verfahren zu seinem Betrieb |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2005085892A1 true WO2005085892A1 (de) | 2005-09-15 |
Family
ID=34917071
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2005/000176 WO2005085892A1 (de) | 2004-03-02 | 2005-01-11 | Magnetfeldsensor und verfahren zu seinem betrieb |
Country Status (5)
Country | Link |
---|---|
US (1) | US7825657B2 (de) |
EP (1) | EP1721183B9 (de) |
JP (1) | JP2007525679A (de) |
DE (1) | DE102004010613B4 (de) |
WO (1) | WO2005085892A1 (de) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102006052692B3 (de) * | 2006-11-08 | 2008-05-15 | Austriamicrosystems Ag | Sensorauswerteanordnung und Verfahren zum Betreiben einer Sensoranordnung |
US9346441B2 (en) | 2010-09-24 | 2016-05-24 | Infineon Technologies Ag | Sensor self-diagnostics using multiple signal paths |
US9638762B2 (en) | 2014-02-24 | 2017-05-02 | Infineon Technologies Ag | Highly efficient diagnostic methods for monolithic sensor systems |
US9874609B2 (en) | 2010-09-24 | 2018-01-23 | Infineon Technologies Ag | Sensor self-diagnostics using multiple signal paths |
US10145882B2 (en) | 2010-09-24 | 2018-12-04 | Infineon Technologies Ag | Sensor self-diagnostics using multiple signal paths |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102004046227B3 (de) | 2004-09-22 | 2006-04-20 | Infineon Technologies Ag | Verfahren zur Herstellung eines Halbleiterbauteils mit Durchkontakten durch eine Kunststoffgehäusemasse und entsprechendes Halbleiterbauteil |
DE102007060707B4 (de) * | 2007-12-17 | 2017-12-07 | Austriamicrosystems Ag | Anordnung zur Detektion einer Bewegung eines Körpers sowie Verfahren zum Betrieb einer solchen Anordnung |
EP2163854A1 (de) * | 2008-09-12 | 2010-03-17 | Austriamicrosystems AG | Sensoranordnung und Messverfahren |
DE102012020515B4 (de) | 2011-10-21 | 2017-04-27 | Tdk-Micronas Gmbh | Stromsensor und Verfahren zur Detektion eines stromlosen Zustands |
DE102012202838A1 (de) | 2012-02-24 | 2013-08-29 | Bombardier Transportation Gmbh | Gelenk für Schienenfahrzeuge oder Schienenfahrzeugteile mit Winkelsensor |
JP6833204B2 (ja) * | 2016-02-25 | 2021-02-24 | セニス エージー | 磁界の角度を測定する角度センサ及び方法 |
DE102016009353B4 (de) | 2016-08-03 | 2021-01-07 | Tdk-Micronas Gmbh | Sensoreinheit und Verfahren für die Detektion eines Gebers an einer vorbestimmten Position |
DE102017208760A1 (de) | 2017-05-23 | 2018-11-29 | Bombardier Transportation Gmbh | Verfahren zur Erkennung einer Entgleisung eines Schienenfahrzeugs |
EP3467443B1 (de) | 2017-10-05 | 2021-08-18 | ams AG | Positionssensor und verfahren zur positionserfassung und diagnostik |
EP3517897B1 (de) * | 2018-01-25 | 2020-10-28 | Melexis Technologies SA | Positionserfassungsvorrichtung |
Citations (4)
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US5426364A (en) * | 1992-08-08 | 1995-06-20 | Yi; Mingguang | Linear hall circuit for measuring magnetic field strength |
US5477135A (en) * | 1993-07-15 | 1995-12-19 | Tektronix, Inc. | Current probe |
DE4422868A1 (de) * | 1994-06-30 | 1996-01-11 | Itt Ind Gmbh Deutsche | Verfahren und Vorrichtung zum Bestimmen eines Drehwinkels eines Magneten |
DE10154498A1 (de) * | 2001-11-07 | 2003-05-22 | Infineon Technologies Ag | Hallsondensystem |
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CH664632A5 (de) * | 1984-08-16 | 1988-03-15 | Landis & Gyr Ag | Schaltungsanordnung zur kompensation von schwankungen des uebertragungsfaktors eines magnetfeldsensors. |
DE59109002D1 (de) * | 1991-07-31 | 1998-07-09 | Micronas Intermetall Gmbh | Hallsensor mit Selbstkompensation |
US5489846A (en) * | 1994-08-03 | 1996-02-06 | United Microelectronics Corp. | Magnetic-field sensor with split-drain MOSFETS |
DE4431703C2 (de) * | 1994-09-06 | 1997-01-30 | Itt Ind Gmbh Deutsche | Magnetfeldsensor mit Hallelement |
EP0740776B1 (de) | 1994-11-22 | 2002-06-12 | Robert Bosch Gmbh | Anordnung zur berührungslosen drehwinkelerfassung eines drehbaren elements |
US6288533B1 (en) * | 1997-05-29 | 2001-09-11 | Physical Electronics Laboratory | Method and apparatus for detecting rotor position by use of magnetic field sensor pairs |
RU2150866C1 (ru) * | 1999-09-20 | 2000-06-20 | Краснодарский научно-исследовательский институт хранения и переработки сельскохозяйственной продукции | Способ производства замутненного напитка |
TWI266887B (en) * | 2002-03-22 | 2006-11-21 | Asahi Kasei Emd Corp | Angle examining apparatus and angle examining system |
-
2004
- 2004-03-02 DE DE102004010613.4A patent/DE102004010613B4/de not_active Expired - Fee Related
-
2005
- 2005-01-11 WO PCT/EP2005/000176 patent/WO2005085892A1/de active Application Filing
- 2005-01-11 JP JP2007501133A patent/JP2007525679A/ja not_active Withdrawn
- 2005-01-11 US US10/591,976 patent/US7825657B2/en active Active
- 2005-01-11 EP EP05700809A patent/EP1721183B9/de not_active Expired - Fee Related
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5426364A (en) * | 1992-08-08 | 1995-06-20 | Yi; Mingguang | Linear hall circuit for measuring magnetic field strength |
US5477135A (en) * | 1993-07-15 | 1995-12-19 | Tektronix, Inc. | Current probe |
DE4422868A1 (de) * | 1994-06-30 | 1996-01-11 | Itt Ind Gmbh Deutsche | Verfahren und Vorrichtung zum Bestimmen eines Drehwinkels eines Magneten |
DE10154498A1 (de) * | 2001-11-07 | 2003-05-22 | Infineon Technologies Ag | Hallsondensystem |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102006052692B3 (de) * | 2006-11-08 | 2008-05-15 | Austriamicrosystems Ag | Sensorauswerteanordnung und Verfahren zum Betreiben einer Sensoranordnung |
US9346441B2 (en) | 2010-09-24 | 2016-05-24 | Infineon Technologies Ag | Sensor self-diagnostics using multiple signal paths |
US9874609B2 (en) | 2010-09-24 | 2018-01-23 | Infineon Technologies Ag | Sensor self-diagnostics using multiple signal paths |
US10145882B2 (en) | 2010-09-24 | 2018-12-04 | Infineon Technologies Ag | Sensor self-diagnostics using multiple signal paths |
US10514410B2 (en) | 2010-09-24 | 2019-12-24 | Infineon Technologies Ag | Sensor self-diagnostics using multiple signal paths |
US9638762B2 (en) | 2014-02-24 | 2017-05-02 | Infineon Technologies Ag | Highly efficient diagnostic methods for monolithic sensor systems |
US10353018B2 (en) | 2014-02-24 | 2019-07-16 | Infineon Technologies Ag | Highly efficient diagnostic methods for monolithic sensor systems |
Also Published As
Publication number | Publication date |
---|---|
JP2007525679A (ja) | 2007-09-06 |
US20070279044A1 (en) | 2007-12-06 |
EP1721183A1 (de) | 2006-11-15 |
US7825657B2 (en) | 2010-11-02 |
EP1721183B1 (de) | 2010-12-08 |
DE102004010613A1 (de) | 2005-10-13 |
EP1721183B9 (de) | 2011-03-02 |
DE102004010613B4 (de) | 2015-04-02 |
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