JP2007537437A - Sensor element and associated angle measurement system - Google Patents

Abstract

With at least one supply terminal (10, 14), in particular with at least one first supply terminal and with at least one reference terminal (12, 16), in particular, for example a ground potential (GND; And at least one supply voltage (VCC; VCC1, VCC2) and at least one supply current (i; i1, i2), respectively, using at least one second supply terminal in GND1, GND2). Between supply voltage (VCC; VCC1, VCC2) drop or supply current (i; i1, i2) flow direction (D; D1, D2) and the resulting internal magnetic field (H _res ) direction Differential voltage (V _out ; V _out1 , V _out2 ) set as a function of angle (α; α1, α2) is at least a first, in particular positive (V +; V + 1, V + 2) Can be tapped between the tapping electrode (20, 24) and at least a second, in particular negative (V-; V-1, V-2) tapping electrode (22, 26), the result The direction of the internal magnetic field (H _res ) resulting from is given by superimposing the intrinsic magnetization (H ₀ ) and at least one external magnetic field (H _ext ), and can be produced without a suitable magnetic orientation, In order to provide at least one magnetoresistive sensor element (100, 110) in which the technically induced offset is minimized or completely eliminated, the magnetoresistive sensor element (100, 110) is flattened. In particular, it is proposed that the drop in supply voltage (VCC; VCC1, VCC2) is continuous.

Description

  The present invention relates to a magnetoresistive sensor element described in the preamble of claim 1.

であることである。 Non-contact angle measurement is a major field of application of magnetoresistive sensors. The reason for this is that the solid effect on which the magnetoresistive sensor is based is an angular effect, ie

It is to be.

  Sensor elements that measure magnetic fields (so-called A [anisotropic] M [magneto] R [resistive] sensors) are based on the principle of anisotropic magnetoresistance effect.

により与えられる。 At present, the AMR angle sensor is first designed as a complete Wheatstone bridge, for example as described in document DE10104453A1. The transfer function of such a complete Wheatstone bridge is

Given by.

However, it is disadvantageous that technical tolerances exist during the manufacture of the individual elongated resistors of the Wheatstone bridge circuit, and these tolerances result in unavoidable asymmetries of the resistors, thereby causing an electrical offset V ₀ is generated. These offsets most of the Wheatstone bridge about 12 millivolts per volt (12mV / V), AMR effect [Delta] [rho] / [rho is determined by _⊥, millivolts per volt is the magnitude order of the signal amplitude (mV / V) Already exists, so that subsequent signal conditioning and removal of such offsets during processing requires excessively high complexity.

ここで、ｔは、前記線形又はバー形抵抗器の厚さであり、
ｗは、前記線形又はバー形抵抗器の幅であり、
Ｍは、パーマロイの飽和磁化（約８００キロアンペア／メートル）であり、これは式、

を介して、内部磁化の角度と外部磁場の角度との間の差をもたらす。ブリッジ出力電圧の奇数調波、ひいては追加の振動角度誤差が、これにより結果として生じる。 Another disadvantage of the bridges known so far is that linear or bar resistors have a non-negligible intrinsic (or internal) magnetic field strength H ₀ ,

Where t is the thickness of the linear or bar resistor,
w is the width of the linear or bar resistor;
M is the saturation magnetization of permalloy (approximately 800 kA / meter), which is

Through the difference between the angle of the internal magnetization and the angle of the external magnetic field. This results in an odd harmonic of the bridge output voltage and thus an additional vibration angle error.

  Therefore, in a Wheatstone bridge circuit, the resistor is designed in the form of a discontinuous long strip, and the specific design of a resistor with a suitable magnetic orientation will affect the magnetic transfer characteristics, so Principle-based magnetoresistive sensors exhibit undesired scattering in the output signal, in particular the Wheatstone bridge circuit to the inner area of the Wheatstone bridge circuit, which is particularly heavily affected, so the ratio of the problematic edge region is Decrease the output signal of the magnetoresistive sensor.

  Based on the above-mentioned disadvantages and drawbacks, in the recognition of the prior art outlined, the object of the present invention can be produced without a suitable magnetic orientation and the technically induced offset is minimized. Or to provide a magnetoresistive sensor element that is completely removed.

  This object is achieved by a magnetoresistive sensor element with the features as claimed in claim 1, an angle sensor with the features as claimed in claim 6, and an angle measuring system with the features as claimed in claim 10. . Advantageous embodiments and advantageous results of the invention are characterized in the respective dependent claims.

  The invention is based on the fact that the magnetoresistive sensor element is designed in the form of a two-dimensional structure and in particular is flat. Therefore, instead of a plurality of linear or bar bridge resistors (→ form a Wheatstone bridge), at least one flat, in particular anisotropic, M [magnetic] R [resistance] element is used.

This two-dimensional structure or flat design of the magnetoresistive element has two crucial advantages compared to the Wheatstone bridge, in particular:
A smaller technically induced electrical offset V ₀ , and
A smaller angular error caused by the internal magnetic field H ₀ ,
Have

  According to the present invention, a layout without a suitable magnetic orientation is thus achieved (in the AMR Wheatstone bridge according to the prior art, such a suitable magnetic orientation results in an oscillating angular error).

  The occurrence of unwanted scattering in the output signal is therefore eliminated by the flat design of the sensor element. Furthermore, because of the flat design of the sensor element, the supply voltage of the magnetoresistive sensor element advantageously drops continuously.

According to one particularly preferred embodiment of the invention, the intrinsic magnetization H ₀ has a low magnetic field strength, so that the resulting internal magnetization H _res is directed essentially parallel to the external magnetic field H _ext .

  Furthermore, in one advantageous embodiment of the sensor element according to the invention, the direction of the differential voltage gradient is oriented essentially perpendicular to the direction of the supply current flow or the drop in the supply voltage.

Advantageously, the sensor element is at least partly made of at least one ferromagnetic alloy, for example permalloy. Nickel-iron alloy permalloy (Ni ₈₀ Fe ₂₀ ) offers the advantage of high permeability with low magnetic field strength and low hysteresis loss at the same time. The magnetic properties of such a ferromagnetic structure can be adjusted by the external shape. Furthermore, permalloy has the property of changing the ohmic resistance by a few percent when passed by a magnetic field.

  In one essential embodiment of the invention, the sensor element can be designed to have more than three poles, in particular using supply terminals and signal taps. In this case, the sensor element advantageously has at least one ground point to form a fixed potential.

  In one advantageous embodiment of the invention, the sensor element may be designed to be essentially rectangular or essentially circular. Independently or in conjunction with this, the sensor element advantageously does not have a suitable magnetic orientation.

  The invention further relates to an angle sensor having at least one sensor element of the type described above and measuring the magnetic field strength, in particular the temporal gradient of the magnetic field strength.

  Such an angle sensor may be designed such that not only a single supply voltage can be applied or only a single supply current flows, but in one advantageous embodiment, The angle sensor is configured such that a first supply voltage drop or a first supply current flow direction has a predetermined angle with respect to a second supply voltage drop or a second supply current flow direction, for example, It may be designed to be rotated or offset by 45 degrees.

In this context, the angle sensor is advantageously
A first sensor element assigned to the first supply voltage or the first supply current, and additionally,
A second sensor element assigned to the second supply voltage or the second supply current;
Can have.

  Instead, in one advantageous embodiment of the angle sensor, the first supply voltage or the first supply current and the second supply voltage or the second supply current are, for example, predetermined in each case. Can be assigned to the same sensor element using terminals that are rotated or offset by a certain angle, for example 45 degrees.

The present invention further provides:
At least one angle sensor of the type described above;
At least one circuit configuration, in particular at least one integrated circuit, which can be supplied with at least one output signal of the angle sensor and is arranged to evaluate the output signal;
A non-contact angle measuring system having

Finally, the present invention
For detecting at least one reference mark when measuring at least one crankshaft angle;
For detecting metal objects,
For measuring rotational speed and / or current,
To detect weak magnetic fields, small in active components of cars or machines, such as at least one drive, at least one metal rod, at least one cam, at least one wheel or at least one gear For detecting movement and / or change, for example,
For detecting and / or controlling traffic movement,
For example, using at least one compass, for navigation purposes, or for non-contact angle measurement
It relates to the use of at least one sensor element of the type described above and / or at least one angle sensor of the type described above and / or at least one angle measuring system of the type described above.

A magnetoresistive sensor device (or magnetoresistive sensor element) of the type described above and / or an angle sensor of the type described above and / or an angle measuring system of the type described above are advantageously
As a proximity sensor,
As a motion sensor or as a position sensor
It can also be used. In this case, it is advantageous to use an external magnetic field that produces a proportional voltage signal of the sensor element when the position of the object to be detected with respect to the source of the external magnetic field changes.

  As already mentioned above, there are various possibilities for advantageously configuring and developing the teachings of the present invention. In this regard, reference is made, on the one hand, to the claims subordinate to claims 1, 6 and 10, while other embodiments, features and advantages of the invention are illustrated in the implementation shown in FIGS. Examples will be described in more detail below with particular reference to exemplary implementations of examples.

  The same or similar configurations, elements or features comprise the same reference numbers in FIGS. 1-7B.

Three embodiments of the sensor element 100 according to the invention are given below. In order to avoid redundant repetition, the following description of the structure, features and advantages of the present invention is (unless otherwise specified)
A first embodiment of the magnetoresistive sensor element 100 shown in FIG.
A second embodiment of the magnetoresistive sensor element 100 shown in FIG.
A third embodiment of the magnetoresistive sensor element 100 shown in FIG.
About.

  In the first embodiment shown in FIG. 1, the sensor element 100 is designed as a flat, essentially rectangular A [anisotropic] M [magnetic] R [resistance] element, in this case the AMR effect. Is shown 50 times larger.

The AMR element 100 is supplied with a supply voltage VCC (hereinafter also referred to as V _CC ) and a supply current i provided by the supply voltage VCC through a supply terminal 10 and a reference terminal 12 at the ground potential GND. . In this case, the terminals 10 and 12 are opposite to each other and are arranged approximately at the center of the side surface of the AMR element 100 having a width w in each case.

The principle of the AMR element 100 is based on the fact that by superimposing the intrinsic magnetization H ₀ and the external magnetic field H _ext of the AMR element 100, the resulting internal magnetic field H _res is generated.

In the AMR element 100 shown in FIG. 1, since the characteristic intrinsic magnetic field strength H ₀ is low (← → no suitable magnetic orientation), the resulting internal magnetization H _res is an external magnetic field even at a low magnetic field strength. _Directed substantially parallel to H _ext , in other words, the direction of the resulting internal magnetization H _res corresponds to the direction of the external magnetic field H _ext . The AMR element 100 therefore has a conductivity ρ _{方向 in} the direction of the external magnetic field H _ext and ρ _垂直 perpendicular to said direction.

ここで、ｆは、０ないし１の（幾何学的）補正因子であり、
ｗは、（ＶＣＣ−ＧＮＤに垂直に規定される）ＡＭＲセンサ素子１００の幅であり、
ｌは、（ＶＣＣ−ＧＮＤに沿って規定される）ＡＭＲセンサ素子１００の長さである。 Direction D (= predetermined direction of current or between supply voltage VCC and ground potential GND, in other words, the direction of voltage drop between supply terminal 10 and reference terminal 12) and direction of external magnetic field H _ext (= essential) Depending on the angle α with respect to the resulting internal magnetic field H _res ), a differential voltage V _out (so-called pseudo-Hall voltage) is set in the AMR element 100, which voltage is Is described by the following equation in a standardized format for the supply voltage VCC.

Where f is a (geometric) correction factor between 0 and 1,
w is the width of the AMR sensor element 100 (defined perpendicular to VCC-GND);
l is the length of the AMR sensor element 100 (defined along VCC-GND).

Due to the external magnetic field H _ext having a predetermined magnetic field angle, for example, when the AMR element 100 is moved, different conductivities in the AMR element 100 are set as described above. These conductivities can be tapped in the form of a differential voltage output signal _Vout .

For this purpose, the AMR element 100 comprises two tapping electrodes 20 and 22, located opposite to each other, in particular
One positive tapping electrode 20 (for tap V + tapping the positive differential voltage _Vout );
One negative tapping electrode 22 (for a tap V− that taps the negative differential voltage V _out );
Have

  The two tapping electrodes 20 and 22 are arranged approximately in the center of the side surface of the AMR element 100 having a length 1 in each case.

  In FIG. 1, the equipotential lines of the AMR sensor 100 are shown using different colors. Here, the outer limit of the color strip in each case corresponds to the equipotential line, and the voltage drop from the complete supply voltage VCC (= 100% VCC) to the ground potential GND (= 0% VCC) is shown in FIG. Again, it is indicated by a strip at the right edge.

FIG. 2 shows the relationship between the (normalized) output signal V _out of the AMR element 100 and the angle α of the external magnetic field H _ext or the resulting internal magnetic field H _res .

This relationship can be attributed to the fact that the resistance R or resistivity ρ of the magnetic conductor changes when an external magnetic field H _ext is applied. When an external magnetic field H _ext is applied parallel to the plane of the magnetic conductor and perpendicular to the current i flowing in the magnetic conductor, the vector of the internal magnetic field H _res of the magnetic conductor rotates by an angle α. The resistance R or resistivity ρ of the magnetic conductor can therefore be arranged with respect to the angle α by the following equation:
ρ = ρ _⊥ + (ρ _‖ −ρ _⊥ ) cos ² α
Where ρ _材料 is a material constant,
ρ _⊥ is a material constant.

  Since the differential output signal V− or V + of the AMR element 100 is proportional to sin2α, the AMR element 100 shown in FIG. 1 can detect an angle range of 90 degrees (see FIG. 2).

In FIG. 2, the angle α (with respect to the direction D of the current i) of the external magnetic field H _ext is plotted on the abscissa, and the normalized output voltage V _{out of the} AMR element 100 shown in FIG. 1 is plotted on the ordinate. Is done. The amplitude of the illustrated output signal of AMR element 100 is 9.5 mV / V, which corresponds to approximately 80 percent of the AMR effect of (about 12 mV / kV).

を示す。 The transfer characteristic of the flat AMR angle sensor element 100 corresponds to that of a known Wheatstone bridge (see prior art). The transfer function of the AMR angle sensor element 100 is thus:

Indicates.

Given a slightly lower amplitude, manufacturing effects on the flat and / or two-dimensional AMR structure 100 produce a significantly lower offset V ₀ than in the case of a full bridge consisting of linear individual resistors. The The use of a flat AMR element 100 instead of a linear resistor (see prior art, see FIGS. 7A and 7B) thus reduces the negative desired electrical offset while having a comparable useful amplitude. As a result, the efficiency in manufacturing an AMR angle sensor can be increased and the complexity during later signal processing can be reduced.

  Another advantage of the new two-dimensional AMR element 100 is that it can be manufactured without a suitable magnetic orientation. In conventional Wheatstone bridges, such a suitable orientation causes an oscillating angular error with an amplitude of up to 0.3 degrees.

  Furthermore, due to the described flat design of the AMR element 100, the temperature coefficient of the electrical offset is also low.

  FIG. 3 shows a flat AMR element 100 with no preferred magnetic orientation. The flat AMR element 100 is formed from a circular permalloy (AMR) layer, and the corresponding electrodes, in particular the supply terminal 10, the positive tapping electrode 20, the reference terminal 12 and the negative tapping electrode 22, are in each case. The circular permalloy (AMR) layers are offset from each other by 90 degrees counterclockwise.

  The amplitude of the output signal of the AMR element 100 shown in FIG. 3 is 11.5 mV / V, and therefore is approximately one fifth higher than the amplitude of the output signal of the AMR element 100 shown in FIG. 1 (see FIG. 2). .

The present invention
The possibility of combining multiple AMR sensor elements 100, 110 (see FIG. 4), or the possibility of using more than two electrodes 20, 22, 24, 26 (see FIG. 6) to tap the differential voltage;
Is also included.

  FIG. 4 illustrates one embodiment of a non-contact angle measurement system 400 having one embodiment of the angle sensor 200. The angle sensor 200 has a first AMR sensor element 100 and a second AMR sensor element 110, which are rotated by a specific angle, in particular 45 degrees, relative to each other.

  In such a configuration, the output signals 210, 212, 214, and 216 of the AMR sensor elements 100 and 110 are the same as the output signals 210 and 212 of the AMR sensor element 100, which are proportional to sin2α and rotated by 45 degrees. Output signals 214 and 216 are proportional to cos2α, thus exhibiting a phase offset of 90 degrees relative to each other.

Such a configuration of the sensor elements 100 and 110 thus makes it possible to detect an angular range of 180 degrees (see FIG. 5). In FIG. 5, the angle α of the external magnetic field H _ext is plotted on the abscissa, and the normalized differential output voltage V _{out of} the AMR elements 100 and 110 is plotted on the ordinate.

In addition to the angle sensor 200, the angle measurement system 400 includes an integrated circuit 300 that evaluates the output signals 210, 212, 214, and 216 of the sensor elements 100 and 110.
A first analog / digital converter 320 that can be supplied with the output signals 210, 212 of the first sensor element 100 and the first output signal 312 of the input buffer 310;
A second analog / digital converter 330 that can be supplied with the output signals 214, 216 of the second sensor element 110 and the second output signal 314 of the input buffer 310;
Have

  In order to determine the angle α1 or α2 from the first output signals 322 and 332 of the analog / digital converters 320 and 330, the integrated circuit 300 is further arranged downstream of the two analog / digital converters 320 and 330. Arithmetic unit 340.

  Further, a fitting unit 350 that can be supplied with the second output signals 324 and 334 of the analog / digital converters 320 and 330 and the output signal 342 of the arithmetic unit 340 in order to adapt the characteristics of the curve to be output. The adaptation unit is connected between the arithmetic unit 340 and the digital / analog converter 360.

  This digital / analog converter 360 further assigned to the integrated circuit 300 can be supplied with the output signal 352 of the adaptation unit 350. In order to buffer the output signal 372 of the integrated circuit 300, an output buffer 370 is provided that can be supplied with the output signal 362 of the digital / analog converter 360.

Finally, the integrated circuit configuration 300 is
An oscillator / clock generator unit 380;
A test / trim unit 382 equipped to test and / or compare the determined values;
A reset unit 384;
Have

FIG. 6 shows a third embodiment of the magnetoresistive sensor element 100. This flat AMR element 100 is designed in a circular shape and has a total of four tapping electrodes 20, 22 and 24, 26 that tap different differential voltages _Vout1 and _Vout2 , respectively.

The first positive tapping electrode 20 and the second negative tapping electrode 22 are arranged opposite to each other, and in each case,
For the supply terminal 10 assigned to the tapping electrodes 20 and 22 and for the reference terminal 12 assigned to the tapping electrodes 20 and 22
Offset by 90 degrees. The first supply voltage VCC1 is applied to the AMR element 100 with respect to the ground potential GND1 using the supply electrode 10 and the reference terminal 12.

The third positive tapping electrode 24 and the fourth negative tapping electrode 26 are likewise arranged opposite to each other, and in each case,
For the supply terminal 14 assigned to the tapping electrodes 24 and 26, and for the reference terminal 16 assigned to the tapping electrodes 24 and 26,
Offset by 90 degrees. The second supply voltage VCC2 is applied to the AMR element 100 with respect to the ground potential GND2 using the supply electrode 14 and the reference terminal 16.

  The third tapping electrode 24 is therefore the first tapping electrode for the supply voltage VCC2 or current i2, and the fourth tapping electrode 26 is therefore the second tapping electrode for the supply voltage VCC2 or current i2.

  The electrodes 14, 16 and 24, 26 are in each case arranged offset by 45 degrees in the clockwise direction with respect to the electrodes 10, 12 and 20, 22. The third embodiment shown in FIG. 6 therefore substantially corresponds to the integrated embodiment of the angle sensor 200 shown in FIG. (In the angle sensor 200 shown in FIG. 4, the electrodes 14, 16 and 24, 26 are assigned to the second sensor element 110, and the second sensor element 110 includes the first electrodes 10, 12 and 20, 22. The sensor element 100 is rotated by 45 degrees in the clockwise direction.)

Due to the described configuration of the electrodes of the flat sensor element 100 shown in FIG. 6, a technical effect similar to that of the angle sensor 200 shown in FIG. 4 is achieved, in other words, the tapping electrode 20, The output signals V _out1 and V _out2 tapped by 22, 24, and 26 show a phase shift equivalent to that in FIG.

To illustrate the difference between the above-described invention and the prior art, a known angle sensor in the form of a so-called double bridge is shown in FIG. 7A. This angle sensor has two Wheatstone bridges offset by 45 degrees relative to each other,
First Wheatstone bridge resistors R1a, R1b, R1c and R1d;
Associated with resistors W2a, R2b, R2c and R2d of the second Wheatstone bridge.

The circuit configuration of such a Wheatstone bridge is shown in FIG. 7B. In addition to the four resistors R1a, R1b, R1c and R1d, the Wheatstone bridge is
A supply terminal for applying a supply voltage VCC;
A grounded reference terminal GND;
And tapping electrodes for tapping a negative output signal V- or negative differential voltage -V _out,
A tapping electrode for tapping a positive output signal V + or a positive differential voltage + _Vout ;
Have

1 schematically shows a first embodiment of a magnetoresistive sensor element according to the invention; Fig. 2 schematically shows the angle between the supply current and the external magnetic field plotted against the normalized output signal of the sensor element of Fig. 1; 2 schematically shows a second embodiment of a magnetoresistive sensor element according to the invention. An embodiment of the angle sensor according to the invention having two sensor elements of FIG. 1 or 3, wherein the two sensor elements are arranged offset by an angle of 45 degrees with respect to each other. 1 schematically illustrates an embodiment of a contact angle measurement system. 5 schematically shows the angles α1 and α2 to be determined plotted in each case against the normalized output signal of the sensor element of FIG. 3 schematically shows a third embodiment of a magnetoresistive sensor element according to the invention. 1 schematically shows a prior art angle sensor in the form of a so-called double bridge. 7B schematically shows a circuit configuration of a Wheatstone bridge according to the prior art for the angle sensor of FIG. 7A.

Explanation of symbols

100: first magnetoresistive sensor element, particularly first anisotropic magnetoresistive sensor element 110: second magnetoresistive sensor element, particularly second anisotropic magnetoresistive sensor element 10: supply terminal, particularly first First supply terminal 12 of the first sensor element 100: a reference terminal (relative to the supply terminal 10), in particular the first potential of the first sensor element 100, for example at the ground potential GND, in particular the first ground potential GND1. 10) first reference terminal 14: supply terminal of the second sensor element 110 (see FIG. 4, second embodiment) or second supply terminal of the first sensor element 100 (FIG. 6, third) See examples)
16: Reference terminal (see FIG. 4, second embodiment) of the second sensor element 110 (relative to the supply terminal 14), for example at ground potential GND, or of the first sensor element 100, for example at ground potential GND2. Second reference terminal (relative to second supply terminal 14) (see FIG. 6, third embodiment)
20: First, particularly positive, tapping electrode 22 of the first sensor element 100: Second, particularly negative, tapping electrode 24 of the first sensor element 100 (relative to the first tapping electrode 20): Second A first, particularly positive, tapping electrode of two sensor elements 110 (see FIG. 4, second embodiment), or a third, particularly positive, tapping electrode of first sensor element 100 (FIG. 6). See the third embodiment)
26: The second, particularly negative, tapping electrode (relative to the first tapping electrode 24) of the second sensor element 110 (see FIG. 4, second embodiment) or the first of the first sensor element 100 4, especially negative, tapping electrode (see FIG. 6, third embodiment)
200: Angle sensor 210: The first output signal of the angle sensor 200, in particular, the positive output signal 212 of the first sensor element 100: The second output signal of the angle sensor 200, particularly the negative of the first sensor element 100 Output signal 214: third output signal of angle sensor 200, in particular positive output signal of second sensor element 110 216: fourth output signal of angle sensor 200, in particular negative output signal of second sensor element 110 300: a circuit configuration for evaluating the output signals 210, 212, 214, 216, particularly the integrated circuit 310: the input buffer 312: the first output signal 314 of the input buffer 310: the second output signal 320 of the input buffer 310: the first Analog / digital converter 322: first output signal 324 of first analog / digital converter 320: first analog / digital converter 3 0 second output signal 330: second analog / digital converter 332: second analog / digital converter 330 first output signal 334: second analog / digital converter 330 second output Signal 340: Arithmetic unit 342: Arithmetic unit 340 output signal 350: Adaptation unit 352: Adaptation unit 350 output signal 360: Digital / analog converter 362: Digital / analog converter 360 output signal 370: Output buffer 372: Angle The output signal of the measurement system 400, in particular the output signal of the circuit arrangement 300, in particular the output signal 380 of the output buffer 370: transducer / clock generator unit 382: test / trim unit 384: reset unit 400: non-contact angle Measurement system α: of supply voltage VCC drop or supply current i flow Angle α between the direction D and the direction of the resulting magnetic field H _res 1: between the direction D1 of the drop of the first supply voltage VCC1 or the flow of the first current i1 and the direction of the resulting magnetic field H _res Angle α2: The angle D between the direction D2 of the drop of the second supply voltage VCC2 or the flow of the second current i2 and the direction of the resulting magnetic field _Hres : The drop of the supply voltage VCC or the flow of the supply current i Direction D1: drop in the first supply voltage VCC1 or first supply current flow direction D2: drop in the second supply voltage VCC2 or second supply current flow direction GND: reference potential, in particular ground potential GND1: first reference potential, in particular the first ground potential GND2: second reference potential, in particular the second ground potential H _0: intrinsic magnetization, in particular intrinsic magnetic field H _ext: the external magnetic field H _res: internal magnetic field resulting : Supply current i1: first supply current i2: second supply current VCC = V _CC: especially against the ground potential GND, and the supply voltage VCC1: especially against ground potential GND2: particularly with respect to the ground potential GND1, the first supply voltage VCC2 , Second supply voltage V _out : voltage difference or differential voltage V _out1 : first voltage difference or first differential voltage V _out2 : second voltage difference or second differential voltage V +: in particular the first tapping electrode Positive differential voltage V _out to be tapped at 20
V + 1: In particular, the positive differential voltage V _out1 to be tapped at the first tapping electrode 20
V-1: Negative differential voltage V _out1 to be tapped especially at the second tapping electrode 22
V + 2: Positive differential voltage to be tapped, particularly at the first tapping electrode 24 (see FIG. 4, second embodiment) or at the third tapping electrode 24 (see FIG. 6, third embodiment) V _out2
V-2: In particular negative to be tapped at the second tapping electrode 26 (see FIG. 4, second embodiment) or at the fourth tapping electrode 26 (see FIG. 6, third embodiment) Differential voltage V _out2

Claims (12)

With at least one supply terminal, in particular with at least a first supply terminal,
With at least one reference terminal, in particular with at least a second supply terminal, for example at ground potential,
A magnetoresistive sensor element capable of being respectively supplied with at least one supply voltage and at least one supply current,
Direction of the supply voltage drop or supply current flow;
Between the direction of the resulting internal magnetic field,
The differential voltage set as a function of angle is
Can be tapped between at least a first, in particular positive, tapping electrode and at least a second, in particular negative, tapping electrode;
In the magnetoresistive sensor element, wherein the direction of the resulting internal magnetic field is given by superimposing the intrinsic magnetization and at least one external magnetic field,
Magnetoresistive sensor element, characterized in that the magnetoresistive sensor element is designed to be flat, in particular the supply voltage drop is continuous.   Sensor element according to claim 1, characterized in that the resulting internal magnetization is directed essentially parallel to the external magnetic field.   Sensor element according to claim 1 or 2, characterized in that the direction of the gradient of the differential voltage is oriented essentially perpendicular to the direction of the supply voltage drop or the supply current flow.   4. Sensor element according to any one of the preceding claims, characterized in that the sensor element is at least partly formed from at least one ferromagnetic alloy, for example permalloy. The sensor element is
Designed to have four or more poles and / or designed to be essentially rectangular or essentially circular and / or have no preferred magnetic orientation,
The sensor element according to any one of claims 1 to 4, wherein the sensor element is characterized in that   6. An angle sensor for measuring a magnetic field strength, in particular a temporal gradient of the magnetic field strength, characterized by at least one sensor element according to any one of claims 1 to 5.   The direction of the first supply voltage drop or the first supply current flow is rotated by a predetermined angle, for example about 45 degrees, with respect to the second supply voltage drop or the second supply current flow direction. The angle sensor according to claim 6, wherein the angle sensor is offset. A first sensor element assigned to the first supply voltage or the first supply current;
A second sensor element assigned to the second supply voltage or the second supply current;
The angle sensor according to claim 7, characterized by a combination of:   The angle sensor according to claim 7, wherein the first supply voltage or the first supply current and the second supply voltage or the second supply current are assigned to the same sensor element. . At least one angle sensor according to any one of claims 6 to 9,
At least one circuit configuration, in particular at least one integrated circuit, which can be supplied with at least one output signal of the angle sensor and is provided for evaluating the output signal;
Non-contact angle measurement system characterized by The circuit configuration is
In particular at least one of the first sensor elements, in particular a first output signal, and at least a first output signal of at least one input buffer;
At least a first analog / digital converter capable of being supplied with
At least one output signal of the second sensor element, or in particular at least one of the first sensor element, in particular a second output signal, and at least a second output signal of the input buffer;
At least one other analog / digital converter that can be supplied with
At least a first output signal of the first analog / digital converter; and at least a first output signal of the other analog / digital converter;
At least one arithmetic unit that can be supplied with
Arranged to determine at least one value, in particular at least one angle, from the first output signal of the analog / digital converter using at least one algorithm, for example using the CORDIC algorithm, The arithmetic unit,
At least one adaptation unit, which can be supplied with the second output signal of the analog / digital converter and the output signal of the arithmetic unit, and which is provided in particular for adapting the characteristics of the curve to be output; ,
At least one digital / analog converter capable of being supplied with the output signal of the adaptation unit;
At least one output buffer and / or at least one transducer / clock generator unit, which can be supplied with the output signal of the digital / analog converter, and in particular is provided for buffering the output signal And / or at least one test / trim unit and / or at least one reset unit, in particular provided for testing and / or comparing said determined value;
The angle measuring system according to claim 10, wherein For detecting at least one reference mark when measuring at least one crankshaft angle;
For detecting metal objects,
For measuring rotational speed and / or current,
Small movements of active parts of a car or machine to detect weak magnetic fields, such as at least one drive, at least one metal rod, at least one cam, at least one wheel, or at least one gear, and / or Or to detect changes,
To detect and / or control traffic movement,
For example, using at least one compass, for navigation purposes, or for non-contact angle measurement
12. At least one sensor element according to any one of claims 1 to 5 and / or at least one angle sensor according to any one of claims 6 to 9 and / or according to claim 10 or 11. Use of at least one angle measurement system.

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