JP2021055999A - Magnetic sensor - Google Patents

Abstract

To provide a magnetic sensor with improved accuracy or reliability.SOLUTION: The magnetic sensor of the present invention includes first to sixteenth magnetoresistive elements provided on a substrate and a detection circuit in which signals are input from the first to sixteenth magnetoresistive elements. Between a first circle and a second circle whose center coincides with the first circle and is larger than the first circle, the first to sixteenth magnetoresistive elements are arranged so as to overlap each other in a region obtained by dividing the second circle into eight equal parts. As a result, variations in offset and amplitude included in the detection signal can be suppressed, so that the accuracy of the detection angle can be improved.SELECTED DRAWING: Figure 18A

Description

The present invention relates to a magnetic sensor used for detecting a steering angle of a vehicle or the like.

Conventionally, a magnetic sensor that detects a steering angle even when the ignition switch is off has been known. As prior art documents relating to such a magnetic sensor, for example, Patent Documents 1 to 3 are known.

Alternatively, a magnetic sensor that uses a magnetoresistive element to detect the rotation of an object including a steering angle or the like is known. As prior art documents relating to such a magnetic sensor, for example, Patent Documents 4 to 6 are known.

Alternatively, a magnetic sensor having a magnetic field generating means and performing a sensor diagnosis based on a magnetic field generated from the magnetic field is known. As prior art documents relating to such a magnetic sensor, for example, Patent Documents 7 and 8 are known.

Alternatively, a magnetic sensor in which a magnetoresistive element and a Hall element are combined is known. As prior art documents relating to such a magnetic sensor, for example, Patent Documents 9 and 10 are known.

Alternatively, a magnetic sensor is known in which two detection systems are provided to improve sensor redundancy. As prior art documents relating to such magnetic sensors, for example, Patent Documents 11, 12, and 13 are known.

Alternatively, a magnetic sensor that detects an external magnetic field using a magnetic resistance film made of a NiFe alloy is known. As prior art documents relating to such magnetic sensors, for example, Patent Documents 14, 15, 16 and 17 are known.

Alternatively, a magnetic sensor in which two sensors are vertically stacked to form one package is known. As prior art documents relating to such magnetic sensors, for example, Patent Documents 18, 19, 20, 21, and 22 are known.

Alternatively, a position detecting device for detecting the position of the shift lever using a magnetic sensor is known. As prior art documents relating to such a position detecting device, for example, Patent Documents 23, 24, and 25 are known.

Alternatively, a rotation detection device using two sets of a magnetic sensor and a magnet is known. As prior art documents relating to such a position detecting device, for example, Patent Documents 26 and 27 are known.

Alternatively, a magnetic sensor including a plurality of resins for sealing or adhering a magnetoresistive element is known. As prior art documents relating to such a position detecting device, for example, Patent Documents 28, 29, and 30 are known.

Alternatively, it is a rotation detection device that uses a magnetic sensor and a magnet, and when correcting the output, the magnetic sensor that calculates the measurement angle by a high-order polynomial based on the value stored in the memory, or the output error is compensated. Rotational detectors that improve sensor placement are known. As prior art documents relating to such a position detecting device, for example, Patent Documents 31 and 32 are known.

Alternatively, for example, a magnetic sensor additionally provided with a magnetoresistive element in order to cancel the harmonic component (= noise component) contained in the output from the magnetoresistive element, or a harmonic signal for correction is used as a sinusoidal signal. , A magnetic sensor that is generated from a cosine signal and cancels harmonic components is known. As prior art documents relating to such a magnetic sensor, for example, Patent Documents 33 and 34 are known.

Alternatively, a magnetic sensor in which a group of magnetoresistive elements are arranged concentrically is known. As prior art documents relating to such a magnetic sensor, for example, Patent Documents 35 and 36 are known.

Japanese Unexamined Patent Publication No. 2015-116964 International Publication No. 2014/148587 Japanese Unexamined Patent Publication No. 2002-213944 Japanese Unexamined Patent Publication No. 2014-209124 Japanese Patent No. 5708896 JP-A-2007-155668 Japanese Patent No. 5620989 Japanese Unexamined Patent Publication No. 6-310776 Japanese Patent No. 4138952 Japanese Patent No. 5083281 Japanese Patent No. 3474096 Japanese Patent No. 48635953 Japanese Patent No. 5638900 Special Fair 4-26227 Gazette Japanese Unexamined Patent Publication No. 2004-172430 Japanese Unexamined Patent Publication No. 2015-082633 Japanese Unexamined Patent Publication No. 2015-108527 Japanese Patent No. 59617777 U.S. Patent Application Publication No. 2015/0198678 U.S. Pat. No. 9,151,809 U.S. Pat. No. 88417776 U.S. Pat. No. 7,906,961 Japanese Unexamined Patent Publication No. 2006-234495 JP-A-2007-333489 Japanese Patent Application Laid-Open No. 2005-521597 Japanese Patent No. 5062450 Japanese Patent No. 5062449 Japanese Unexamined Patent Publication No. 2015-38507 Japanese Unexamined Patent Publication No. 2015-41701 Japanese Unexamined Patent Publication No. 2014-866777 JP-A-2009-150795 Japanese Unexamined Patent Publication No. 2011-158488 Japanese Unexamined Patent Publication No. 2017-161391 JP-A-2007-107886 Japanese Patent No. 5991031 Special Table 2007-516415

However, the above-mentioned conventional magnetic sensor is insufficient to meet the ever-increasing demand for high accuracy and high reliability.

Therefore, the present invention provides a magnetic sensor with improved accuracy or reliability.

In order to solve the above object, the present invention includes first to sixteen magnetoresistive elements provided on a substrate and a detection circuit in which signals are input from the first to sixteenth magnetoresistive elements. Here, the first to sixteenth magnetoresistive elements form the second circle between the first circle and the second circle whose center coincides with the first circle and is larger than the first circle. The configuration is such that they are placed on top of each other in an equally divided area.

Since the magnetic sensor of the present invention has high accuracy or high reliability, it is useful as a magnetic sensor used for detecting the steering angle of a vehicle, for example.

Block diagram of the magnetic sensor of this embodiment Schematic diagram of rotation detection device using the same magnetic sensor Schematic diagram of another rotation detection device using the same magnetic sensor Schematic diagram of another magnet included in the rotation detector The figure explaining the operation of the detection circuit of the magnetic sensor The figure explaining another operation of the detection circuit of the magnetic sensor The figure explaining another operation of the detection circuit of the same magnetic sensor. The figure explaining the method of detecting the rotation of the magnetic sensor. A diagram for explaining yet another operation of the detection circuit of the magnetic sensor, (a) a flowchart for explaining the operation of the automatic correction circuit 70e, and (b) a conceptual diagram for explaining the operation of correction. Waveform diagram showing the output of the magnetic sensor The figure explaining another operation of the detection circuit of the magnetic sensor. Block diagram of another magnetic sensor of this embodiment Top view of magnetoresistive sensor Front view of magnetic sensor Front view of another magnetic sensor of this embodiment Top view of the magnetic sensor Front view of yet another magnetic sensor of this embodiment Front view of yet another magnetic sensor of this embodiment Perspective view of the magnetic sensor of FIG. Another perspective view of the magnetic sensor of FIG. Top view of the magnetoresistive element of FIG. FIG. 17A is a cross-sectional view taken along the line PP'. (A) Cross-sectional view of the MR layer included in the conventional magnetoresistive sensor as a comparative example, (b) Cross-sectional view of the MR layer included in the magnetoresistive sensor of the present embodiment. Top view of magnetoresistive sensor Top view of magnetoresistive sensor Front view of magnetic sensor Three-view view of yet another magnetic sensor of this embodiment The figure explaining the operation of each magnetic sensor of this embodiment. The figure explaining the operation of each magnetic sensor of this embodiment. Perspective view of the detection device of this embodiment Top view of the detection device Block diagram of the magnetic sensor included in the detection device The figure explaining the manufacturing method of still another magnetic sensor of this embodiment. The figure explaining the manufacturing method of the magnetic sensor The figure explaining the manufacturing method of the magnetic sensor The figure explaining the manufacturing method of the magnetic sensor The figure explaining the manufacturing method of the magnetic sensor The figure explaining the manufacturing method of the magnetic sensor The figure explaining the manufacturing method of the magnetic sensor Perspective view of the magnetic sensor Perspective view of another detection device of this embodiment Top view of a part of the detection device Perspective view of yet another detection device of this embodiment Top view of a part of the detection device Perspective view of yet another detection device of this embodiment Top view of a part of the detection device Perspective view of yet another detection device of this embodiment Top view of a part of the detection device Front view of yet another magnetic sensor of this embodiment Front view of yet another magnetic sensor of this embodiment Front view of yet another magnetic sensor of this embodiment Front view of yet another magnetic sensor of this embodiment Front view of yet another magnetic sensor of this embodiment Front view of yet another magnetic sensor of this embodiment

Hereinafter, the magnetic sensor according to the embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of the magnetic sensor of the embodiment.

The magnetic sensor 100 includes a magnetoresistive element 12 and a detection circuit 10 that is electrically connected to the magnetoresistive element 12.

The magnetoresistive element 12 includes a sinusoidal first magnetic resistance 12a, a sinusoidal second magnetic resistance 12b, a sinusoidal third magnetic resistance 12c, and a sinusoidal fourth magnetic resistance 12d. Further, the magnetoresistive element 12 includes a cosine first magnetic resistance 12e, a cosine second magnetic resistance 12f, a cosine third magnetic resistance 12g, and a cosine fourth magnetic resistance 12h. Each magnetoresistive is a metal pattern having a magnetoresistive effect containing an iron-nickel alloy, which is provided on a substrate such as silicon, and the electric resistance is increased according to a change in the direction and magnitude of a magnetic field given from the outside. Change. Each reluctance may be described as a "magnetic resistance pattern". The sine first magnetic resistor 12a to the sine fourth reluctance 12d constitute the first bridge circuit WB1. That is, the first bridge circuit WB1 connects a circuit in which the sine first magnetic resistance 12a and the sine third magnetic resistance 12c are connected in series, and the sine second magnetic resistance 12b and the sine fourth magnetic resistance 12d in series. The circuits are connected in parallel to form a circuit. Further, one end of the first bridge circuit WB1 is connected to the potential VS, and the other end is grounded to ground (GND in the figure).

The second cosine circuit WB2 is composed of the first reluctance of the cosine and the fourth reluctance of the cosine of 12h. That is, the second bridge circuit WB2 connects a circuit in which the cosine first reluctance 12e and the cosine third reluctance 12g are connected in series, and the cosine second reluctance 12f and the cosine fourth reluctance 12h in series. The circuits are connected in parallel to form a circuit. Further, one end of the second bridge circuit WB2 is connected to the potential VC, and the other end is grounded to ground (GND in the figure).

Here, the first bridge circuit WB1 is arranged so as to be rotated by 45 ° with respect to the second bridge circuit WB2. In another expression, the second bridge circuit WB2 is arranged so as to be rotated by 45 ° with respect to the first bridge circuit WB1.

Here, the magnetic sensor 100 is arranged in the vicinity of a magnet that is connected to a rotating member (for example, a steering shaft or the like) that is an object to be measured via a gear or the like. At this time, the resistance value of each reluctance changes according to the change of the external magnetic field (or the rotating magnetic field) given from this magnet. Therefore, from the connection portion between the sinusoidal first magnetic resistance 12a and the sinusoidal third magnetic resistance 12c constituting the first bridge circuit WB1, and the connection portion between the sinusoidal second magnetic resistance 12b and the sinusoidal fourth magnetic resistance 12d, Two sinusoidal signals that are 180 ° out of phase with each other are output. At the same time, from the connection portion between the cosine first reluctance 12e and the cosine third reluctance 12g constituting the second bridge circuit WB2, and the connection portion between the cosine second reluctance 12f and the cosine fourth reluctance 12h. However, two cosine wave-like signals whose phases are 180 ° different from each other are output. The first bridge circuit WB1 obtains a sinusoidal signal from the first bridge circuit WB1, whereas the second bridge circuit WB2 obtains a cosine wave-like signal from the first bridge circuit WB1 and the second bridge circuit WB2. This is because they are arranged so as to be rotated by 45 °.

Here, the two signals output from the first bridge circuit WB1 are referred to as + sin signal and −sin signal, and the two signals output from the second bridge circuit WB2 are referred to as + cos signal and −cos signal.

The detection circuit 10 receives + sin signal, -sin signal, + cos signal, and -cos signal, and performs various signal processing such as amplification and AD conversion for + sin signal, -sin signal, + cos signal, and -cos signal. It has a configuration to be performed.

The signal from each magnetoresistive element can be described as a "first rotation signal".

Hereinafter, the configuration and operation of the detection circuit 10 will be specifically described.

The first amplifier 14a amplifies the + sin signal.

The second amplifier 14b amplifies the −sin signal.

The third amplifier 14c amplifies the + cos signal.

The fourth amplifier 14d amplifies the −cos signal.

The offset adjustment circuit 15 is connected to the input stages of the first amplifier 14a, the second amplifier 14b, the third amplifier 14c, and the fourth amplifier 14d, respectively, and has a midpoint potential difference between the + sin signal and the −sin signal, and a + cos signal. The midpoint potential difference between the −cos signals is adjusted to 0.

The first differential amplifier 16a differentially amplifies the + sin signal and the −sin signal output from the first bridge circuit WB1 to generate a sin signal having twice the amplitude. This sin signal may be described as a "first signal".

The first bridge circuit wb1 can be described as a first magnetoresistive element, and the signal from the first bridge circuit wb1 can be described as a first detection signal.

The second differential amplifier 16b differentially amplifies the + cos signal and the −cos signal output from the second bridge circuit WB2 to generate a cos signal having twice the amplitude. This cos signal may be described as a "second signal".

The second bridge circuit wb2 can be described as a second magnetoresistive element, and the signal from the second bridge circuit wb2 can be described as a second detection signal.

The gain adjustment circuit 17 is connected to each of the first differential amplifier 16a and the second differential amplifier 16b, and the gain of the amplifier is adjusted so that the amplitude of the sin signal and the cos signal after differential amplification becomes a predetermined amplitude. To adjust.

With this configuration, it is not necessary to adjust the offset gain for each of the amplifier stages, so that the signal can be adjusted once for both the offset gain adjustment. This especially contributes to the miniaturization of the circuit.

If the offset / gain adjustment is described in another expression, it can be described as follows, for example.

The correction method of the magnetic sensor 100 of the present embodiment includes a first step of amplifying the output of the bridge circuits wb1 and wb2, a second step of correcting the offset of the output of the bridge circuits wb1 and wb2, and an output corrected for the offset. A third step of amplifying the above and a fourth step of correcting the gain of the output corrected for the offset are provided.

The first AD converter 18a A / D-converts the signal from the first differential amplifier 16a at a predetermined sampling cycle and outputs it as a sin signal (digital signal).

The second AD converter 18b A / D-converts the signal from the second differential amplifier 16b at a predetermined sampling cycle and outputs it as a cos signal (digital signal).

The first Hall element 40a is a Hall element having detection sensitivity for a magnetic field in a direction perpendicular to or parallel to the circuit board on which the detection circuit 10 is provided, and has a direction and magnitude of the above-mentioned external magnetic field (rotating magnetic field). Detects the change in and outputs the detection signal.

The second Hall element 40b is a Hall element having detection sensitivity with respect to a magnetic field in a direction perpendicular to or parallel to the circuit board on which the detection circuit 10 is provided, and has the direction and magnitude of the external magnetic field (rotating magnetic field) described above. Detects changes and outputs a detection signal.

The signal from each Hall element can be described as a "second rotation signal".

The first amplifier 42a amplifies the signal from the first Hall element 40a.

The second amplifier 42b amplifies the signal from the second Hall element 40b.

The first comparator 44a converts the signal from the first amplifier 42a into a first pulse signal which is a rectangular wave signal.

The second comparator 44b converts the signal from the second amplifier 42b into a first pulse signal which is a rectangular wave signal.

Here, the first Hall element 40a is arranged so as to be rotated by 90 ° with respect to the second Hall element 40b (in another expression, the second Hall element 40b is rotated by 90 ° with respect to the first Hall element 40a). Is placed). Therefore, the first pulse signal (in another expression, the first Hall element 40a) and the second pulse signal (the signal from the second Hall element 40b) are signals having a phase difference of 90 degrees from each other.

The first regulator 60b supplies a potential (first potential) to the first oscillator 80a. Further, a potential (first potential) is supplied to the first Hall element 40a, the second Hall element 40b, and the amplifier in the detection circuit 10 that processes the signals from each Hall element.

The second regulator 60c supplies a potential (first potential) to the second oscillator 80b. The second regulator 60c supplies the potential used for the intermittent operation of the Hall element (details will be described later).

The third regulator 60a supplies a potential (first potential) to the magnetoresistive element 12 and the amplifier or the like in the detection circuit 10 that processes the signal from the magnetoresistive element 12.

The arithmetic circuit 70 includes an angle detection circuit 70a, a rotation speed detection circuit 70b, an offset temperature characteristic correction circuit 70c, and a gain temperature characteristic correction circuit 70d.

The angle detection circuit 70a detects the rotation angle of the magnet described above from the sin signal (digital signal), the cos signal (digital signal), the first pulse signal, and the second pulse signal, and outputs a signal (Vout). Specifically, the rotation angle is detected by performing an arctan operation on the sin signal and the cos signal. The angle detection circuit 70a outputs an angle signal representing the rotation angle after performing the arctan calculation. In another expression, the angle detection circuit 70a receives a sin signal (first signal) and a cos signal (second signal). The angle detection circuit 70a converts a sin signal (first signal) and a cos signal (second signal) to generate and output an angle signal (which may be described as a third signal). The angle detection circuit 70a may be referred to as an arctan circuit.

The rotation speed detection circuit 70b measures the rotation speed of the magnet described above from the first pulse signal and the second pulse signal. The method of measuring the rotation speed will be described later.

The offset temperature characteristic correction circuit 70c corrects the DC offset generated in the sin signal (digital signal) or the cos signal (digital signal) due to the resistance variation of each magnetoresistive element. The correction method will be described later.

The gain temperature characteristic correction circuit 70d corrects the gain (amplitude) offset generated in the sin signal (digital signal) or the cos signal (digital signal) due to the temperature change of each magnetic resistance element. As the method, for example, how the sin signal (digital signal) or the cos signal (digital signal) changes according to the temperature is measured in advance, and the measured value is held by the memory in the detection circuit 10. .. Then, the measured value in the memory is read out based on the temperature information obtained from the temperature sensor 80d. Then, the measured value read from the memory is superimposed on the sin signal (digital signal) or the cos signal (digital signal). This achieves temperature offset correction.

The first oscillator 80a is an oscillation circuit for generating an internal clock used in the detection circuit 10. The internal clock generated by the first oscillator 80a is used for detecting the magnetoresistive element 12 and each Hall element.

The second oscillator 80b is an oscillation circuit for generating another internal clock used in the detection circuit 10.

Here, the signal generated by the first oscillator 80a (in another expression, the first clock signal) has a first frequency, and the signal generated by the second oscillator 80b (in another expression, the second clock signal). Has a second frequency, the second frequency is lower than the first frequency.

The memory 80c stores the rotation speed measured by the rotation speed detection circuit 70b described above, the measured value used for correcting the temperature offset, and the like.

FIG. 2A (a) is a schematic view of a rotation detection device 150 using the magnetic sensor 100.
The rotation detection device 150 includes a magnetic sensor 100, a detection target magnet 142, a rotation shaft 144 that supports the detection target magnet 142, a bearing 146 that supports the rotation shaft 144, and a motor 158 that rotates the rotation shaft 144. ..

FIG. 2A (b) is a schematic view showing an example of a control system using the rotation detection device 150.

The control system includes a steering wheel 152, a steering torque 154, a torque sensor 156, a motor 158, a magnetic sensor 100, and an ECU 160 (electronic control device). When the driver rotates the steering wheel 152 to switch the direction of the vehicle, the connected steering torque 154 rotates in the same direction as the rotation. The torque sensor 156 detects the relative rotational displacement of the input shaft and the output shaft accompanying the rotation of the steering wheel 152, and transmits an electric signal to the ECU 160. The motor 158 is a motor for assisting the steering wheel 152 and the steering torque 154, and assists the driver to easily switch the direction of the automobile. A magnetic sensor 100 is attached to the motor 158 to control the motor by detecting the rotation angle of the motor.

FIG. 2B is a schematic view of a rotation detection device 150b using the magnetic sensor 100. The Z axis in the figure coincides with the extending direction of the rotating shaft 144. The X-axis and the Y-axis are perpendicular to the Z-axis and pass through the center of the magnet 142 to be detected.

The rotation detection device 150b includes a magnetic sensor 100, a detection target magnet 142, a rotation shaft 144 that supports the detection target magnet 142, an upper magnetic sensor 100, and a lower magnetic sensor 100. The "upper side" may be described as "the positive side of the rotation axis 144 (Z axis in the figure)". The "lower side" may be expressed as "the negative side of the rotation axis 144 (Z axis in the figure)". The width of the rotating shaft 144 (the width in the direction along the X axis in the figure) is indicated as D1.

The detection target magnet 142 has a first surface 142a supported by the rotation axis 144 and perpendicular to the rotation axis 144 (Z axis in the drawing), and a second surface 142b facing the first surface 142a. The width of the detection target magnet 142 in the direction along the rotation axis 144 (Z axis in the figure) is indicated as D2 (twice D2). The first surface 142a side of the detection target magnet 142 is the S pole. The second surface 142b side of the detection target magnet 142 is the north pole. In another expression, it may be described that "the detection target magnet 142 has opposite polarities on the surface facing the upper magnetic sensor 100 and the surface facing the lower magnetic sensor 100". The detection target magnet 142 has a polarity opposite to that on the positive side of the X-axis and that on the negative side of the X-axis.

The upper magnetic sensor 100 is provided with a first surface 142a and a first interval (D1).
The upper magnetic sensor 100 is provided with a second interval (D2) from the rotating shaft 144. In other words, the distance between the upper magnetic sensor 100 and the rotating shaft 144 is equal to the width of the rotating shaft 144.

The lower magnetic sensor 100 is provided with a first interval (D1) from the second surface 142b. The lower magnetic sensor 100 is provided with a second interval (D2) from the rotating shaft 144. In other words, the distance between the lower magnetic sensor 100 and the rotating shaft 144 is equal to the width of the rotating shaft 144.

That is, the distance between the upper magnetic sensor 100 and the rotating shaft 144 is equal to the distance between the lower magnetic sensor 100 and the rotating shaft 144. Further, the distance between the upper magnetic sensor 100 and the detection target magnet 142 is equal to the distance between the lower magnetic sensor 100 and the detection target magnet 142. Further, the first interval (D1) is smaller than the second interval (D2). As an example, the first interval (D1) is 1 mm and the second interval (D2) is 5 mm.

By the way, a noise magnetic field may be applied in addition to the magnet 142 generated by the detection target magnet 142 (that is, the rotating magnetic field to be detected). The noise magnetic field includes, for example, a magnetic field leaking from a motor. When the noise magnetic field is applied to the magnetic sensor in this way, the magnetic sensor detects the combined magnetic field of the rotating magnetic field and the noise magnetic field. Therefore, when the direction of the magnetic field to be detected and the direction of the noise magnetic field are different, an error occurs in the detection angle of the magnetic sensor.

Here, in the rotation detection device 150b, since the positive and negative signs of the noise components contained in the output signals of the upper magnetic sensor 100 and the lower magnetic sensor 100 are opposite to each other, the upper magnetic sensor 100 and the lower magnetic sensor 100 are lower. By taking the differential of the output from the magnetic sensor 100 on the side, the noise component caused by the noise magnetic field can be offset.

The magnet 142 to be detected may be divided into two as shown in FIG. 2C. That is, it is described that "the first surface 142a side of the detection target magnet 142 is the south pole. The second surface 142b side of the detection target magnet 142 is the north pole", but the detection target magnet 142 in this sentence is shown in FIG. It also includes a configuration such as 2C.

FIG. 3 is a diagram illustrating the operation of the magnetic sensor 100 included in the magnetic sensor 100 of the present embodiment. FIG. 3 is a flowchart for explaining the operation of the magnetic sensor 100 for detecting the movement of the steering wheel while the ignition is on (hereinafter, may be referred to as “IGon”).

First, after starting the magnetic sensor 100 sensor (S300), the magnetic sensor 100 starts detecting the rotation angle (S302 and S303). Then, each magnetoresistive element of the magnetic sensor 100 executes a calculation for detecting the rotation angle (S302). Then, the magnetic sensor 100 executes two detections, quadrant discrimination and rotation speed detection, based on the output of each Hall element (S303). The rotation angle, rotation speed, etc. obtained by the above calculation (calculation of S302 and S303) are transmitted from the magnetic sensor 100 to an external microcomputer or the like.

FIG. 4 is a diagram illustrating another operation of the magnetic sensor 100 of the present embodiment. FIG. 4 is a flowchart for explaining the operation of the magnetic sensor 100 for detecting the movement of the steering wheel during the ignition off (hereinafter, may be referred to as “IGoff”).

First, when IGoff is performed, a control command signal is input to the magnetic sensor 100 from a control system (for example, a steering system) provided on the vehicle body side (S401). Then, when this control command signal is input, the magnetic sensor 100 shifts to the intermittent operation mode (in other words, the low power consumption mode) (S402). Then, the magnetic sensor 100 holds the normal rotation speed (that is, the final rotation speed before the transition to the intermittent operation mode) at the time of transition to the intermittent operation mode (S403). At the same time, the configuration of the magnetoresistive element 12 and the detection circuit 10 used for signal processing from the magnetoresistive element 12 (for example, the first to fourth amplifiers, the offset adjustment circuit 15, the gain adjustment circuit 17, the first and second AD converters). Etc.) to sleep (that is, stop energization) (S404). Then, the magnetic sensor 100 detects only the rotation speed of the member to be detected at regular time intervals by using the output signal of each Hall element (S405). Then, the magnetic sensor 100 holds the rotation speed detected during the intermittent operation mode in the memory 80c (S406). Then, a control command signal is input to the magnetic sensor 100 from a control system (for example, a steering system) provided on the vehicle body side at the time of Igon (S408). Then, the magnetic sensor 100 receives this control command signal and shifts to the normal mode (S409). Then, the angle of the member to be detected at that time is detected by using the signals of each magnetoresistive element and each Hall element only once at the time of transition to the normal mode (S410, S411). Then, this detection result and the rotation speed at the start of the intermittent operation mode (that is, the final rotation speed before the transition to the intermittent operation mode) are simultaneously transmitted to an external microcomputer or the like. The term "simultaneous" as used herein is not construed as being limited to the meaning that two outputs are output at exactly the same time, and includes a case where they are output at substantially the same time.

In the intermittent operation mode, the second clock signal generated by the second oscillator 80b is used for various operations (processes) of the detection circuit 10. This is because the frequency of the second oscillator is determined according to the intermittent operation cycle, so efficiency such as power consumption is good, and mutual monitoring (diagnosis) of oscillators can be performed by using two oscillators. ..

FIG. 5 is a diagram illustrating still another operation of the detection circuit 10 included in the magnetic sensor of the present embodiment. FIG. 5 is a waveform diagram for explaining an operation in which each Hall element of the magnetic sensor 100 detects the movement of the steering wheel during the ignition off.

First, in general, in a magnetoresistive element, a signal composed of waveforms of Sin2θ and Cos2θ is obtained with respect to the rotation angle θ of the member to be detected. Therefore, it is equipped with only a magnetoresistive element and can only detect up to 180 degrees with a magnetic sensor (for such a magnetic sensor, for example, 90 degrees and 270 degrees are the same signal and cannot be discriminated).

On the other hand, in general, in a Hall element, as shown in FIG. 5, a signal composed of waveforms of Sin θ and Cos θ with respect to the rotation angle θ of the member to be detected can be obtained. Therefore, a magnetic sensor equipped with a Hall element can detect up to 360 degrees.

The magnetic sensor 100 of the present embodiment detects the rotation angle of the member to be detected at 360 degrees by using the magnetoresistive element and the Hall element in combination.

FIG. 6 is a diagram illustrating a method in which the magnetic sensor 100 of the present embodiment detects rotation. FIG. 6 is a waveform diagram for explaining an operation in which each magnetoresistive element of the detection circuit 10 detects the movement of the steering wheel during the ignition off.

First, a first pulse signal and a second pulse signal, which are pulses of signals from each Hall element, such as the A-phase and B-phase outputs of the encoder, are generated.

Since the first pulse signal and the second pulse signal are used for quadrant discrimination, 1 (Pulse / Revolution) and 4 (Counts / Revolution) signals are generated. Specifically, at the rising and falling edges of the first pulse signal, the state of the second pulse signal is confirmed and counted. An example of calculating the number of rotations will be described below.

When the first pulse signal rises from the state where the second pulse signal is 0, when the first pulse signal falls, when the second pulse signal rises from the state where the second pulse signal rises, and when the first pulse signal rises. When the second pulse signal transitions to the state of 0, it is detected as "forward rotation + 1 rotation".

When the first pulse signal rises, the second pulse signal is High, when the first pulse signal falls, the second pulse signal is 0, and when the first pulse signal rises, the second pulse signal is High. When the state changes, it is detected as "reversal + 1 rotation".

With this configuration, when detecting the rotation angle of the motor that has moved during IGoff, it is possible to detect with higher accuracy and lower power than before when the IGon is changed again.

FIG. 7A is a diagram illustrating still another operation of the detection circuit 10 included in the magnetic sensor 100 of the present embodiment. FIG. 7A is a diagram for explaining the operation of the detection circuit 10 for correcting the output from the magnetoresistive element 12, and FIG. 7A (a) is a flowchart for explaining the operation of the automatic correction circuit 70e, FIG. 7A (b). ) Is a conceptual diagram for explaining the operation of the correction.

By the way, the arithmetic circuit 70 of the magnetic sensor 100 has "auto calibration mode (first correction mode or active correction mode)" and "active correction mode" for correcting the sin signal and cos signal output from the magnetoresistive element 12. It is equipped with a special temperature correction mode (second correction mode or passive correction mode).

First, the "warm special correction mode (second correction mode or passive correction mode)" will be described.

The memory 80c stores the coefficients when the dependence of the offset on the temperature is approximated by a polynomial function for each of the sin signal and the cos signal output from the magnetoresistive element 12. In addition, the coefficients when the dependence of the gain (that is, amplitude) of each of the sin signal and the cos signal after the A / D conversion with respect to the temperature are approximated by a polynomial function are stored.

The offset temperature characteristic correction circuit 70c performs arithmetic processing using the temperature information (digital signal) input from the temperature sensor 80d and the coefficient related to the temperature dependence of the offset stored in the memory 80c, thereby performing a sin signal / cos. Correct the temperature characteristics of the signal offset.

The gain temperature characteristic correction circuit 70d performs arithmetic processing using the temperature information (digital signal) input from the temperature sensor 80d and the coefficient related to the temperature dependence of the gain stored in the memory 80c, thereby performing a sin signal / cos. Corrects the temperature characteristics of the signal gain.

Next, the "auto calibration mode (first correction mode or active correction mode)" will be described.

The automatic correction circuit 70e generates and updates a correction value used for correcting the offset and gain of the sin signal and the cos signal from the magnetoresistive element 12 every time the member to be detected makes one rotation. Then, the updated correction value is used so that the sin signal and the cos signal from the magnetoresistive element 12 always have a constant midpoint / amplitude. Such a magnetoresistive element obtained while the member to be detected makes the next one rotation by generating and updating a correction value based on the signal from the magnetoresistive element 12 obtained during one rotation of the member to be detected. The operation of correcting the signal from No. 12 is the operation of "auto calibration".

When the auto-calibration is ON, the automatic correction circuit 70e always uses the magnetoresistive element 1
The maximum value Vmax and minimum value Vmin of the sin signal and cos signal from 2 are held (peak hold, S703), and when the rotated member makes one rotation, the offset is (Vmax + Vmin) / 2 and the gain is (Vmax). -Vmin) is calculated to generate a correction value for correcting the offset gain, and each is updated (S705). At the same time, the Vmax / Vmin values are reset to 0 (S706).

Then, the sin signal and the cos signal are corrected based on the updated offset gain value until the next one rotation is completed.

Then, again, the Vmax and Vmin values are maintained until the next one rotation is completed, and the same operation is repeated thereafter.

It should be noted that the determination of whether or not "one rotation" has been made is performed when the angle output value after arctan jumps from 360 degrees to 0 degrees (forward rotation) or when it jumps from 0 degrees to 360 degrees (reverse rotation). , If the direction of forward / reverse rotation is different from the previous value, it is not regarded as "1 rotation", and in such a case, the correction value is not updated. More specifically, it will be explained as follows.

In the case of the previous forward rotation (arrow 1 in FIG. (7b)) and the current normal rotation (arrow 2 in FIG. (7b)) as shown in FIG. 7A (b) A, it is regarded as "1 rotation" and the automatic correction circuit 70e Performs the operation of updating the correction value.

In the case of the previous normal rotation (arrow 2 in FIG. (7b)) and the current normal rotation (arrow 3 in FIG. (7b)) as shown in FIG. 7 (b) B, it is regarded as "1 rotation" and the automatic correction circuit 70e Performs the operation of updating the correction value.

Similarly, in the case of the previous inversion and the current inversion, it is regarded as "1 rotation", and the automatic correction circuit 70e performs an operation of updating the correction value.

In the case of the previous forward rotation (arrow 4 in FIG. (7b)) and the inversion this time (arrow 5 in FIG. (7b)) like C in FIG. 7A (b), it is not regarded as "1 rotation" and the automatic correction circuit 70e Does not update the correction value.

Although it has been explained that the operation of updating the correction value is not performed, the operation of generating the correction value may be stopped.

In the case of the previous inversion (arrow 6 in FIG. (7b)) and the forward rotation this time, as in E in FIG. 7A (b), (arrow 7 in FIG. 7B) "not regarded as one rotation, the automatic correction circuit 70e Does not update the correction value.

With this configuration, even if the offset gain (amplitude) of the sin signal and cos signal of the magnetic sensor element changes with time, the adjustment value is updated one by one to always maintain a constant offset gain (amplitude). be able to. At the same time, even when the member to be detected rotates both forward and reverse, the offset can be updated accurately.

When the "auto calibration mode (first correction mode or active correction mode)" is ON, the "warm special correction mode (second correction mode or passive correction mode)" is OFF, and "auto calibration" is set. When the "mode (first correction mode or active correction mode)" is OFF, it is preferable to operate so that the "warm special correction mode (second correction mode or passive correction mode)" is ON. In other words, the magnetic sensor 100 switches between "auto calibration mode (first correction mode or active correction mode)" and "warm special correction mode (second correction mode or passive correction mode)". It works. With this configuration, when the auto-calibration mode is ON, all changes over time including the temperature feature are corrected, so that the temperature feature correction mode can be turned off. On the other hand, in the auto-calibration mode, the correction value is not updated until the member to be rotated makes one rotation, so that the auto-calibration is performed in an application that does not make one rotation or an application in which the offset gain value changes significantly until one rotation. It is preferable to use the passive correction mode rather than the rotation mode.

In the description of the auto-calibration mode, the case of correcting both the offset and the gain has been described, but the present invention is not limited to this. That is, a mode in which only the offset or only the gain is corrected may be used.

In the description of the auto-calibration mode and the temperature special correction mode, the case of correcting the sin signal and the cos signal of the magnetoresistive element from the magnetoresistive element has been described, but the present invention is not limited to this. It does not have to be a reluctance as long as it is a magnetically responsive element that outputs a sin signal and a cos signal according to the rotation of the member to be detected. That is, the auto-calibration mode and the temperature special correction mode can be used for correction of the sin signal and the cos signal of the magnetic element.

The operation of the automatic correction circuit 70e in the auto-calibration mode can be expressed in another expression. Specifically, it can be described as follows. The automatic correction circuit 70e rotates forward from normal rotation when the angle signal output from the angle detection circuit 70a changes from 360 degrees to 0 degrees, and reverses when it changes from 0 degrees to 360 degrees. , Or when the change from inversion to inversion is performed, the correction value is generated and / or updated.

The operation of the automatic correction circuit 70e in the auto-calibration mode can be expressed in yet another expression. Specifically, it can be described as follows.

In the auto-calibration mode, the first step of generating and updating the correction value from the differential signal of the sin signal and the cos signal, and whether the member to be detected rotates in the order of "forward rotation to reverse rotation" or "reverse rotation to normal rotation". Rotation detection including a second step to be detected and a third step to stop the first step when it is detected that the rotation is in the order of "forward rotation to reverse rotation" or "reverse rotation to normal rotation" in this second step. This is a correction method for the device.

Here, a preferable example of the offset correction method will be described.

First, it is assumed that the sin signal and the cos signal are expressed as the following equations 1 and 2 by ignoring the harmonic components of the third order or higher included in the sin signal and the cos signal.

Here, θ is the magnetic field angle, AS1 is the amplitude of the Sin signal, AC1 is the amplitude of the Cos signal, AS2 is the amplitude of the second harmonic signal included in the Sin signal, and AC2 is the second harmonic contained in the Cos signal. The amplitude of the signal, AS0 is the offset of the Sin signal, and AC0 is the offset of the Cos signal. Approximating that AS1 = AC1 = A1 and AS2 = AC2 = A2, and calculating the angle from the outputs of Equation 1 and Equation 2,

Here, assuming that AS0 = 0 and AC0 = A2,

Will be. That is, the value used for the offset correction of Cos is adjusted appropriately (non-zero value) instead of the correction that sets the offset (AS0, AC0) to 0. As a result, the influence of the second harmonic component on the angle error can be almost eliminated. The method of this offset correction will be described in another expression. Offset correction in which the value used for offset correction of the Sin signal is 0, and the value used for offset correction of the Cos signal is the amplitude of the second harmonic component contained in the Cos signal or Sin signal (that is, AS2 or AC2). It can be said that it is a method.

On the other hand, in the above description regarding auto-calibration, a method of offset correction in which the automatic correction circuit 70e makes AS1 and AC1 equal to each other and the offset AS0 and the offset AC0 are both set to 0 has been described. When this operation is applied to each signal expressed by Equation 1 and Equation 2,

Here, if AS1 = AC1 and AS0 = AC0 = 0, then

Will be. That is, in the offset correction method described in the description of the operation of auto-calibration, although a certain effect can be obtained, an angle error (Δθ) due to the second harmonic remains. On the other hand, the method of offset correction described in Equations 1 to 4 can make the influence of the second harmonic component on the angle error almost zero. Therefore, the offset can be corrected with high accuracy.

By the way, the method of offset correction described in Equations 1 to 4 can be executed by the automatic correction circuit 70e, the offset temperature characteristic correction circuit 70c, the offset adjustment circuit 15, and the like. In another expression, the detection circuit 10 executes the offset correction method described in Equations 1 through 4.

By the way, the automatic correction circuit 70e can have yet another correction mode (hereinafter, the correction mode may be described as 11.25 correction mode). This will be described with reference to FIG. 7B and the like.

FIG. 7B is a waveform diagram showing the output of the magnetic sensor. In detail, the distortion component of the angle signal (which may be expressed as the third signal) representing the rotation angle after the angle detection circuit 70a performs the arctan calculation is shown. In FIG. 7B, the horizontal axis represents the mechanical angle, and the vertical axis represents the distortion component included in the angle signal representing the rotation angle after performing the arctan calculation. As can be seen from FIG. 7B, the inventors have found that the distortion component of an angular signal (or may be described as a "distortion waveform", "distortion signal", etc.) has a period of approximately 45 deg.

FIG. 7C is a diagram illustrating the operation of the automatic correction circuit 70e in the 11.25 correction mode. FIG. 7C (a) is a waveform diagram before correction, and FIG. 7C (b) is a waveform diagram after correction. The black dots in FIG. 7 indicate the positions where the distortion components are corrected.

As shown in FIG. 7C (a), the 11.25 correction mode corrects the distortion component for each 11.25 deg section. As described above, since the strain component has a period of about 45 deg, the correction is performed every 11.25 deg section, so that the correction of the strain component can be performed with high accuracy as shown in FIG. 7C (b). Will be done.

It should be noted that "correction for each 11.25 deg section" can also be expressed as "correction for each 32 sections (360 deg / 11.25 deg = 32 sections)". Further, a multiple of 32 sections (64 sections, 96 sections, 128 sections, etc.) may be applied as a section for correction. The 11.25 correction mode can also be expressed as "correcting the signal for each section of the (1 / 32n) period of the signal (such as + sin) output by the magnetoresistive element 12 with n as a natural number".

It is also possible to connect the peaks of the distortion waveform and correct them. In this case, the automatic correction circuit 70e preferably operates in such a way that correction is performed every 22.50 deg section (correction is performed every 16 sections (360 deg / 22.50 deg = 16 sections)). Further, a multiple of 16 sections (32 sections, 48 sections, etc.) may be applied as a section for correction.

Summarizing the above, the operation of the automatic correction circuit 70e can be described as follows. The automatic correction circuit 70e corrects the angle signal for each section of the (1 / 16n) period of the period of the angle signal, where n is a natural number.

FIG. 8 is a block diagram showing a modified example of the magnetic sensor of the present embodiment. Hereinafter, a modified example of FIG. 8 will be described.

One end of the sinusoidal first magnetic resistor 12a and one end of the sinusoidal second magnetic resistor 12b are connected to the potential Vs.

One end of the sinusoidal third magnetoresistor 12c and one end of the sinusoidal fourth magnetoresistive 12d are connected to the ground (GND in the figure).

The other end of the sinusoidal reluctance 12a is connected to the detection circuit 10 via the wiring 100a1.

The other end of the sinusoidal reluctance 12b is connected to the detection circuit 10 via the wiring 100a2.

The other end of the sinusoidal reluctance 12c is connected to the detection circuit 10 via the wiring 100a3.

The other end of the sinusoidal fourth magnetic resistor 12d is connected to the detection circuit 10 via the wiring 100a4.

In another expression, the other ends of each of the sinusoidal first to fourth magnetoresistors are connected to the detection circuit 10 via wirings 100a1 to 100a4.

Inside the detection circuit 10, the connection point A between the other end of the sinusoidal reluctance 12a and the other end of the sinusoidal reluctance 12c (in another expression, the midpoint A constituting the first bridge circuit wb1). Is formed.

The signal at the connection point A (midpoint A) is input to the first amplifier 14a, amplified, and input to the first differential amplifier 16a.

Inside the detection circuit 10, the connection point B between the other end of the sinusoidal second magnetic resistor 12b and the other end of the sinusoidal fourth magnetic resistor 12d (in another expression, the middle point B constituting the first bridge circuit wb1). Is formed.

The signal at the connection point B (midpoint B) is input to the second amplifier 14b, amplified, and input to the first differential amplifier 16a.

The other end of the cosine first reluctance 12e is connected to the detection circuit 10 via the wiring 100b1.

The other end of the second magnetic resistor 12f of the cosine is connected to the detection circuit 10 via the wiring 100b2.

The other end of the cosine third magnetic resistor 12g is connected to the detection circuit 10 via the wiring 100b3.

The other end of the cosine fourth magnetoresistor 12h is connected to the detection circuit 10 via the wiring 100b4.

In another expression, the other end of each of the first to fourth magnetoresistors of the cosine is connected to the detection circuit 10 via the wirings 100b1 to 100b4.

The wiring is, for example, a metal wire (wire bonding).

Inside the detection circuit 10, the connection point C between the other end of the cosine first reluctance 12e and the other end of the cosine third reluctance 12g (in another expression, the midpoint C constituting the second bridge circuit wb2). Is formed.

The signal at the connection point C (midpoint C) is input to the third amplifier 14c, amplified, and input to the second differential amplifier 16b.

Inside the detection circuit 10, the connection point D between the other end of the cosine second reluctance 12f and the other end of the cosine fourth reluctance 12h (in another expression, the midpoint D constituting the second bridge circuit wb2). Is formed.

The signal at the connection point D (midpoint D) is input to the fourth amplifier 14d, amplified, and input to the second differential amplifier 16b.

The second bridge circuit wb2 can be described as a second magnetoresistive element, and the signal from the second bridge circuit wb2 can be described as a second detection signal.

The disconnection detection of the wirings 100a1 to a4 and 100b1 to b4 connecting the magnetoresistive element 12 and the detection circuit 10 will be described.

In normal operation, the potentials of the ground points A, B, C and D, which are the input signals from the magnetoresistive element 12, are close to the midpoint potential, and as a result, the first amplifier 14a to the fourth amplifier 14d, the first differential amplifier The output of 16a and the output of the first AD converter 18a is near the midpoint. On the other hand, when any one of the wirings 100a1 to a4 and 100b1 to b4 is cut, the grounding point of the cut portion of the magnetoresistive element 12 is fixed to High (VS or VC) or Low (GND). The outputs of the first amplifier 14a to the fourth amplifier 14d, the first differential amplifier 16a, the second differential amplifier 16b, and the first AD converters 18a and 18b are fixed to High or Low. As a result, the diagnostic circuit A90 detects that the output of the first AD converter 18a or the second AD converter 18b is out of the normal operation range, diagnoses it as an abnormality determination, and outputs an abnormality signal. With this configuration, it is possible to detect disconnection between the magnetoresistive element 12 and the detection circuit 10 at the connection portion.

It is detected that the output of the first AD converter 18a or the second AD converter 18b is out of the normal operating range (in other words, a predetermined range, a predetermined voltage range, etc.) is detected, and a diagnosis is made as an abnormality. The case where an abnormal signal is output has been described, but the present invention is not limited to this. For example, it may be detected that the output of the first differential amplifier 16a or the second differential amplifier is out of the normal operating range, diagnosed as an abnormality determination, and an abnormality signal may be output.

If the configuration of FIG. 8 is expressed in another description, it can be described as follows. A first substrate provided with a bridge circuit (wb1 or wb2) composed of first to fourth reluctances (sine first to fourth reluctances or cosine first to fourth reluctances) and connected to the first to fourth reluctances. The first, second, third, and fourth wirings (100a1 to 100a4 or 100b1) are connected between the second substrate including the detection circuit 10 and one end of each of the first, second, third, and fourth magnetoresistors and the detection circuit 10. ~ 100b4) and. Here, the midpoint of the bridge circuit is provided on the second substrate.

Next, the resistance value abnormality detection of the magnetoresistive element 12 will be described.

The magnetoresistive element 12 is connected to the third regulator 60a inside the detection circuit 10 by the changeover switches 110a and 110b via the current detection resistors 112a and 112b or by direct connection (without resistance). Normally, the current path directly connected to the third regulator 60a is selected for the changeover switches 110a and 110b, and the changeover switches 110a and 110b pass through the resistors 112a and 112b only when the resistance value of the magnetoresistive element 12 is diagnosed. It is a current path connected to the third regulator 60a. Here, the diagnostic circuit B91 is connected to the third regulator 60a and measures the voltage across the resistors 112a and 112b. Alternatively, the current value flowing through each resistor is measured. At this time, if some trouble occurs in the magnetoresistive element 12 and an abnormality occurs in the resistance value, or if the VS and VC wires are broken, the amount of current flowing through the resistors 112a and 112b is usually the amount. Out of range. The diagnostic circuit B91 determines that an abnormality has occurred due to the deviation from this range, and outputs an abnormality signal. With this configuration, it is possible to detect an abnormality in the resistance value of the magnetoresistive element 12 and wire disconnection with VS and VC. Failure can be detected even when the sheet resistance of the magnetoresistive element 12 changes (that is, the resistances of the four magnetoresistive elements constituting the bridge circuit change at the same time).

After the period in which the current path connected to the third regulator 60a via the resistor 112a is selected (that is, the period in which the diagnosis of the first bridge circuit wb1 is performed), the first bridge circuit wb1 is diagnosed via the resistor 112b. 3 It is preferable to provide a period during which the current path connected to the regulator 60a is selected (that is, a period during which the diagnosis of the second bridge circuit wb is performed). As a result, the current value flowing through the first bridge circuit wb1 and the current value flowing through the second bridge circuit wb2 are sequentially input to the diagnostic circuit B91, so that the circuit scale of the diagnostic circuit B91 is not increased. The bridge circuit wb1 of 1 and the bridge circuit wb2 of the second can be diagnosed.

The changeover switch 110a may be referred to as a first switch, the changeover switch 110b may be referred to as a second switch, the resistor 112a may be referred to as a first resistor, and the resistor 112b may be referred to as a second resistor. Further, the electric path leading to the magnetic resistance element 12 without passing through the first resistor 112a is passed through the first current path, and the electric path passing through the first resistance 112a to the magnetic resistance element 12 is passed through the second current path and the second resistance 112b. The electric path leading to the magnetic resistance element 12 may be described as a third current path, an electric path passing through the second resistor 112b to the magnetic resistance element 12, and a fourth current path. Further, it may be described that the diagnostic circuit B91 is connected to the second current path and the fourth current path. Further, the resistance value of the second current path is larger than that of the first current path. It can be said that the fourth current path has a larger resistance value than the third current path. The operation of the diagnostic circuit B91 can be described in another expression. For example, it can be described as follows.

The diagnostic method carried out by the diagnostic circuit B91 is a method including the following first to sixth steps.

In the first step, the potential is supplied from the third regulator 60a to the first bridge circuit wb1 via the first current path.

In the second step, the potential is supplied from the third regulator 60a to the first bridge circuit wb1 via the second current path (which has a larger resistance than the first current path).

The third step supplies the potential via the third current path from the third regulator 60a to the second bridge circuit wb2.

In the fourth step, the potential is supplied from the third regulator 60a to the second bridge circuit wb2 via the fourth current path (which has a larger resistance than the third current path).

The fifth step generates an error signal when the current value of the second step is larger / smaller than a predetermined value.

The sixth step generates an error signal when the current value of the fourth step is larger / smaller than a predetermined value.

It is preferable that the second and fifth steps and the fourth and sixth steps are carried out before and after each other, not at the same time. As a result, the current value flowing through the first bridge circuit wb1 and the current value flowing through the second bridge circuit wb2 are sequentially input to the diagnostic circuit B91, so that the circuit scale of the diagnostic circuit B91 is not increased. The bridge circuit wb1 of 1 and the bridge circuit wb2 of the second can be diagnosed.

FIG. 9 is a top view of the magnetic sensor 100. FIG. 10 is a front view of the magnetic sensor 100. In FIG. 9, some configurations are omitted. FIG. 9 shows a magnetic sensor 100 in the case of using a vertical Hall element that detects a magnetic field in a direction parallel to the circuit board on which the detection circuit 10 is provided. In the following description, the sinusoidal reluctances 12a to 12d are collectively referred to as "first reluctance group 12i", and the cosine first reluctances 12e to 12h are collectively referred to as "second reluctance group 12j". May be done.

The magnetic sensor 100 includes a magnetoresistive element 12, a detection circuit 10, a die pad 130, a wire 134, a sealing resin 138, and a lead 132.

A magnetoresistive element 12 and a detection circuit 10 are placed on the die pad 130.

The sealing resin 138, the magnetoresistive element 12, the detection circuit 10, and the die pad 130 are sealed.

The lead 132 extends from the sealing resin 138 to make an electrical connection with the outside.

The straight line L1 in FIG. 9 passes through substantially the center of the sinusoidal first magnetic resistance 12a to the sinusoidal fourth magnetic resistance 12d and the cosine first magnetic resistance 12e to the cosine fourth magnetic resistance 12h. Here, the first Hall element 40a and the second Hall element 40b are provided line-symmetrically with respect to the straight line L1. More specifically, the first Hall element 40a and the second Hall element 40b are provided at an angle of 45 ° with respect to the straight line L1. In another expression, the straight line L4 passing through the substantially center of the straight line L3 passing through the substantially center of the first Hall element 40a is parallel to the magnetoresistance pattern possessed by any one of the reluctance first magnetic resistance 12a to the sinusoidal fourth magnetic resistance 12d. is there. The straight line L5 passing through the substantially center of the second Hall element 40b is parallel to the magnetic resistance pattern of any one of the sinusoidal first magnetic resistance 12a to the sinusoidal fourth magnetic resistance 12d.

The second Hall element 40b is obtained by rotating the first Hall element 40a by 90 °.

Since both the first Hall element 40a and the second Hall element 40b are vertical Hall elements that detect a magnetic field in a direction parallel to the circuit board on which the detection circuit 10 is provided, a circuit in which a magnetic field in a direction parallel to the circuit board can be easily obtained. It is preferable to provide it near the center of the substrate.

FIG. 11 is a front view of another magnetic sensor 100a according to the present embodiment. FIG. 12 is a top view of the magnetic sensor 100a. In FIG. 12, some configurations are omitted. In the following description, the sine first reluctance 12a to the sine fourth reluctance 12d included in the magnetoresistive element 121 are collectively referred to as "first reluctance group 121a", and the cosine first magnetic resistance possessed by the magnetoresistive element 121. The 12e to the fourth reluctance of the cosine, 12h, may be collectively referred to as the “second reluctance group 121b”. Similarly, the sine first reluctance 12a to the sine fourth reluctance 12d included in the magnetoresistive element 122 are collectively referred to as the “first reluctance group 122a”, and the reluctance first magnetic resistance 12e to the cosine first of the magnetoresistive element 122. 4 The reluctance 12h may be collectively referred to as “second reluctance group 122b”. The detection circuit 10a may be referred to as a "first circuit board", and the detection circuit 10b may be referred to as a "second circuit board".

The magnetic sensor 100a includes a magnetoresistive element 121, a magnetoresistive element 122, a detection circuit 10a, a detection circuit 10b, a die pad 130, a wire 134, a sealing resin 138, a lead 132a, and a lead 132b.

Magnetoresistive elements 121 and 122 and detection circuits 10a and 10b are placed on the die pad 130.

The sealing resin 138 seals the magnetoresistive elements 121 and 122, the detection circuits 10a and 10b, and the die pad 130.

The leads 132a and 132b extend from the sealing resin 138 to electrically connect to the outside.

A signal from the magnetoresistive element 121 is input to the detection circuit 10a. The configuration and operation of the detection circuit 10a are the same as the configuration and operation of the detection circuit 10.

A signal from the magnetoresistive element 122 is input to the detection circuit 10b. The configuration and operation of the detection circuit 10b are the same as the configuration and operation of the detection circuit 10.

The magnetoresistive element 121 and the magnetoresistive element 122 are symmetrical with respect to the straight line L1 in FIG. Alternatively, the substantially center of the first reluctance group 121a, the substantially center of the second reluctance group 121b, the approximately center of the first reluctance group 122a, and the approximately center of the second reluctance group 122b pass through the straight line L2. By providing the magnetoresistive element 121 and the magnetoresistive element 122 in this way, the redundancy of the sensor can be improved, so that the reliability is improved.

Further, on the side close to the magnetic sensor 100a, the end face of the magnetoresistive element 121 and the end face (of the first circuit board) of the detection circuit 10a are provided so as to coincide with each other. In another expression, in top view, the end face of the magnetoresistive element 121 and the end face (of the first circuit board) of the detection circuit 10a pass through the straight line L3.

Further, on the side close to the magnetic sensor 100a, the end face of the magnetoresistive element 122 and the end face (of the second circuit board) of the detection circuit 10b are provided so as to coincide with each other. In other words, in top view, the end face of the magnetoresistive element 122 and the end face (of the second circuit board) of the detection circuit 10b pass through the straight line L4.

Further, the detection circuit 10a and the detection circuit 10b each have an electrode group that is electrically connected to a magnetoresistive element or a reed. Here, in this electrode group, the first electrode group 126a and the second electrode group 12
It consists of 6b. The first electrode group 126a and the second electrode group 126b are parallel to the straight lines L5 and L6. In this way, the electrode group (and the wire connected to it) is kept away from the straight line L5 (that is, the center of each magnetoresistive element). This makes it less susceptible to interference from the electrode group (and the wires connected to it) and improves the accuracy of the magnetic sensor.

FIG. 13 is a front view of yet another magnetic sensor 100b according to the present embodiment.

The magnetic sensor 100b includes a magnetoresistive element 121, a magnetoresistive element 121, a detection circuit 10a, a detection circuit 10b, a die pad 130a, a die pad 130b, a wire 134, a sealing resin 138, and a lead 132.

In the magnetic sensor 100b, the magnetoresistive element 122 is arranged on the magnetoresistive element 121. Here, the center of the magnetoresistive element 121 and the center of the magnetoresistive element 122 are arranged so as to substantially coincide with each other. In another expression, the center of the magnetoresistive element 121 and the center of the magnetoresistive element 122 pass through the straight line C1. By doing so, since the center of the magnetoresistive element 121 and the center of the magnetoresistive element 122 are close to each other, the signals obtained from the magnetoresistive element 121 and the magnetoresistive element 122 can be made substantially the same, which is preferable.

Further, the magnetic sensor 100b has a portion 136 that does not overlap with the magnetoresistive element 122 in a top view, or, in other words, a portion 136 that projects from the magnetoresistive element 121. Part 136 is an extension of the substrate constituting the magnetoresistive element 121. In other words, the width of the substrate constituting the first magnetoresistive element 121 is longer than the width of the substrate constituting the second magnetoresistive element 122, and is larger than the width of the substrate constituting the second magnetoresistive element 122. The long part is the overhanging part 136. The portion 136 is a portion for obtaining a region for providing the wire 134b, and by providing the portion 136, the centers of the magnetoresistive element 121 and the magnetoresistive element 122 can be substantially aligned with each other. It is preferable because the signals obtained from the magnetoresistive element 122 and the magnetoresistive element 122 can be made substantially the same. As shown in FIG. 14, the die pad 130 may be divided. Such a structure in which the die pad is divided can also be adopted in the magnetic sensor 100a of FIG.

FIG. 15 is a perspective view of the magnetic sensor 100b, and FIG. 16 is another perspective view of the magnetic sensor 100b. In FIG. 15, some configurations are omitted or simplified. In FIG. 16, a part of the configuration is omitted from FIG.

The first magnetoresistive element 121 has a third electrode group 127a. The second magnetoresistive element 122 has a fourth electrode group 127b.

The third electrode group 127a is provided on the portion 136 protruding from the first magnetoresistive element 121. The third electrode group 127a is arranged along the straight line L7.

The fourth electrode group 127b is provided on the second magnetoresistive element 122. The fourth electrode group 127b is arranged along the straight line L8. Here, the straight line L7 and the straight line L8 are parallel to each other.

Although it has been described that the magnetic sensor 100 is attached to the steering wheel 152 and the motor for assisting the steering torque 154, the present invention is not limited to this. For example, it can be used to detect the lever position of a shift lever of an automobile. That is, the magnetic sensor 100 can be used independently by itself.

FIG. 17A is a front view of each magnetoresistive element of the present embodiment. FIG. 17B is a cross-sectional view taken along the line PP'of FIG. 17A.

The fourth magnetoresistive cosine resistance 12h includes a silicon substrate 181, a silicon dioxide layer (SiO2 layer) provided on the silicon substrate 181 and an MR layer 185 (magnetic resistance layer) provided on the silicon dioxide layer, and an MR layer. A titanium layer 187 (Ti layer) provided on the 185, a wiring layer 189 provided on the titanium layer 187 (Ti layer), a first protective layer 183 provided on the MR layer 185, and a first protection. It has a second protective layer 184 provided on the layer 183.

The wiring layer 189 is wiring used for electrical connection between the MR layer 185 and the detection circuit 10. For example, it is composed of gold (Au). The wiring layer 189 has a portion exposed from the second protective layer 184 and is electrically connected to the outside. The wiring layer 189 may be referred to as a gold layer, a metal layer, an electrode layer, or the like. The Ti layer 187 is an adhesion layer between the wiring layer 189 and the MR layer 185.

The first protective layer 183 is a protective layer that protects the MR layer 185. The first protective layer 183 is provided so as to cover the upper surface of the MR layer 185 and the side surface of the MR layer 185. In FIG. 17B, the width of the first protective layer 183 between the MR layer 185 and the second protective layer 184 is indicated by T2. T2 is 1.5 nm or more. Here, the film thickness T2 of the MR layer 185 is set to 15 nm or less (details will be described later). Therefore, there is a feature that T1 / T2 is larger than 1/10. By providing the first protective layer 183, the adhesion between the protective film and the MR layer is improved, and the reliability with respect to humidity can be improved. Further, when the Young's modulus of the second protective layer 184 is high, it can be expected to work to alleviate the stress effect.

The second protective layer 184 is provided on the first protective layer 183 and is a layer made of silicon dioxide (SiO2), a fluoride-based resin, or the like. By providing the second protective layer 184, it is possible to protect the MR layer 185 from oxidation due to oxygen in the air at high temperature and humidity, mechanical scratches, and corrosion due to direct contact from all other chemical substances. It becomes.

The first protective layer 183 and the second protective layer 184 can be collectively referred to as a "protective layer".

In the MR layer 185, a nickel iron alloy is formed (filmed) on a silicon dioxide layer (SiO2 layer) by a sputtering method or the like. More specifically, the MR layer 185 obtains a thin and homogeneous MR layer 185 by applying high kinetic energy to the sample atom (nickel-iron alloy), increasing the degree of vacuum, and performing sputtering at a low gas pressure. be able to.

Here, the width of the MR layer 185 (W in FIG. 17B) is 15 μm or more, and the thickness of the MR layer (T1 in FIG. 17B) is 15 nm or less. That is, the aspect ratio (T1 / W) in the cross section of the MR layer is set to 1/1000 or less. As a result, the apparent anisotropic magnetic field Ha of the MR layer can be lowered. Here, the apparent anisotropic magnetic field Ha is expressed by the following equation.

Ha = 4πMs ・ (T / W) ・ ・ ・ ・ ・ ・ (Equation 1)
In Equation 1, T: the thickness of the MR layer, W: the width of the MR layer, 4πMs: the constant of the physical property value.

Here, the MR layer has an apparent anisotropic magnetic field Ha <12 (Oe). This can be done by setting the film thickness to 15 nm or less and the width of the MR layer to 15 μm or more according to Equation 1. As a result, even if a rotating signal magnetic field of 12 Oe or more is applied, the fluctuation waveform of the output signal magnetic field becomes a substantially ideal sine wave. In addition, since the magnetic field strength is output to infinity and the waveform shape and voltage hardly change, if the magnetic field strength of the magnet is sufficiently high and the decrease in the signal magnetic field due to temperature change is set to 12 Oe or more, it is caused by the magnet. The temperature characteristics of the output voltage can be virtually ignored, facilitating the circuit configuration.

FIG. 17C (a) is a cross-sectional view of the MR layer included in the conventional magnetoresistive sensor as a comparative example, and FIG. 17C (b) is a cross-sectional view of the MR layer included in the magnetoresistive sensor of the present embodiment. is there. As shown in FIG. 17C (a), in the MR layer provided in the conventional magnetoresistive sensor, the domain wall (boundary between magnetic domains and magnetic domains) in the longitudinal direction of the MR layer in the cross-sectional view (and / or top view) after patterning. ) Are aligned. This is possible by setting the substrate temperature to 200 ° C. or higher and making the MR layer a film thickness of 25 nm or higher by ion beam deposition or the like so that the grain size of crystal grains has a certain size. With this film forming means, since the crystal grains have an island-like structure at 25 nm or less, it is impossible to further reduce the film thickness. Furthermore, when the current consumption is taken into consideration, the width of the MR layer must be reduced in order to increase the resistance value, so Ha becomes large as is clear in Equation 1, and the waveform distortion of the sine wave when the signal magnetic field angle is detected. Becomes noticeable, and the detection accuracy deteriorates.

On the other hand, as shown in FIG. 17C (b), in the MR layer included in the magnetoresistive sensor of the present embodiment, the metal material constituting the MR layer (in the present embodiment) in cross-sectional view (and / or top view). In the form, there are no crystal grains of nickel-iron alloy). Further, the MR layer has anisotropy (direction of magnetization) in the film thickness direction (in other words, the direction perpendicular to the MR layer silicon substrate or the silicon dioxide layer). This is because the film thickness is 15 nm or less, so that the thickness is not sufficient to form crystal grains, and the substrate temperature is set to 25 ° C. or less during sputtering, which makes it impossible to generate crystal grains. However, it becomes difficult to magnetize in the horizontal direction. In other words, with respect to a magnetic field in a direction substantially parallel to the substrate, magnetization reversal in the MR layer becomes easy, and the state becomes almost magnetically saturated at a low magnetic field (magnetized in a direction parallel to the main surface of the silicon substrate). ). Therefore, the amount of superposition of the factors for changing the magnetic field strength is smaller than the angle detection in the magnetic field direction substantially parallel to the substrate, so that the angle detection signal can be detected almost as theoretically. In addition, "there is no crystal grain" can be interpreted as meaning that there is no crystal grain in the cross section perpendicular to the longitudinal direction of the magnetoresistive film as shown in FIG. 17C (b). Further, the cross section of all the reluctance films appearing in the same cross section is not limitedly interpreted in the sense that no crystal grains are present, and the cross section of at least one reluctance film (enclosed by the broken line A in FIG. 17B). The cross section of the reluctance film appearing in the region can be interpreted as meaning that there are no crystal grains in the "cross section of one reluctance film").

Here, when the magnetic sensor of the present embodiment is used in the rotation detection device, the magnetic field of the magnet 142 to be detected (may be described as “signal magnetic field”) is generally preferably 20 mT or more. The reason is that when used as an in-vehicle magnetic sensor, a large power generation generator, motor, etc. are often mounted in the vicinity of the magnetic sensor, and the influence of the fluctuating magnetic field generated from the coil built in these is affected. Since the possibility of receiving the signal is high, it is possible to reduce these effects by setting the detected signal magnetic field strength as high as possible.

By the way, with reference to FIGS. 11 to 16 and the like, a magnetic sensor including a magnetoresistive element 121, a magnetoresistive element 122, a detection circuit 10a, and a detection circuit 10b has been described (these magnetic sensors can improve sensor redundancy. it can). In these magnetic sensors, two systems each of a magnetoresistive element and a detection circuit are provided. However, it is not limited to this. The magnetoresistive element 121 and the magnetoresistive element 122 may be combined into one chip. Such a case will be described with reference to FIGS. 18A, 18B, and 18C.

18A and 18B are top views showing another magnetoresistive element 123, 124 of the present embodiment. FIG. 18C is a schematic cross-sectional view of a magnetic sensor 100 m including the magnetoresistive element 123 or the magnetoresistive element 124. The magnetic sensor 100m includes a magnetoresistive element 123 or a magnetoresistive element 124, a detection circuit 10a, a detection circuit 10b, a die pad 130, a wire 134, a sealing resin 138, a lead 132a, and a lead 132b.

A signal from the magnetoresistive element 123 (124) is input to the detection circuit 10a. The configuration and operation of the detection circuit 10a are the same as the configuration and operation of the detection circuit 10.

A signal from the magnetoresistive element 123 (124) is input to the detection circuit 10b. The configuration and operation of the detection circuit 10b are the same as the configuration and operation of the detection circuit 10. The magnetoresistive element 123 (124) includes a magnetoresistive element 121 and a magnetoresistive element 122.

The sine first reluctance 12a to the sine fourth reluctance 12d possessed by the magnetoresistive element 121 are collectively referred to as "first reluctance group 121a", and the reluctance first magnetic resistance 12e to the cosine fourth reluctance possessed by the magnetoresistive element 121. 12h may be generically described as "second magnetoresistive group 121b". Similarly, the sine first reluctance 12a to the sine fourth reluctance 12d included in the magnetoresistive element 122 are collectively referred to as the “first reluctance group 122a”, and the reluctance first magnetic resistance 12e to the cosine first of the magnetoresistive element 122. 4 The reluctance 12h may be collectively referred to as “second reluctance group 122b”.

The 16 reluctances (first reluctance group 121a, second reluctance group 122b) possessed by the magnetoresistive element 123 are placed on a substrate having an XY plane as a main surface composed of X-axis and Y-axis orthogonal to each other. It is provided. Further, the 16 magnetoresistors of the magnetoresistive element 123 are arranged between the first circle (circle A) and the second circle (circle B). The first and second circles are centered on each other. The second yen is larger than the first yen. Further, the 16 magnetoresistors of the magnetoresistive element 123 have a set that is line-symmetrical with respect to a predetermined straight line. Here, the predetermined straight line passes through the center of the first circle and has an inclination of 45 n ° with respect to the X axis (where n is 0, 1 or 2). The two reluctances included in a set may be described as "one reluctance" and "the other reluctance".

The 16 magnetoresistors (first magnetoresistive group 121a, second magnetoresistive group 122b) included in the magnetoresistive element 124 are arranged between the first circle (circle A) and the second circle (circle B). .. The first and second circles are centered on each other. The second yen is larger than the first yen.

The 16 magnetoresistors (first magnetoresistive group 121a, second magnetoresistive group 122b) included in the magnetoresistive element 124 are arranged so as to overlap each other in a region obtained by dividing the circle A (or the circle B) into eight equal parts. Here, "arranged in layers" may also be described as "the convex portion of one reluctance enters the concave portion of the other magnetic resistor". With the above configuration, outputs having the same phase can be obtained from the first reluctance group 121a and the first reluctance group 122a of the other reluctance. Similarly, outputs of the same phase can be obtained from the second reluctance group 121b and the other reluctance group 122b. As a result, variations in the offset voltage and output amplitude can be suppressed, so that the detection angle accuracy is improved. The diagnostic circuit 90A may be a part of the arithmetic circuit 70.

FIG. 19 is a diagram showing still another magnetic sensor 100d of the present embodiment. 19A shows a top view of the magnetic sensor 100d, FIG. 19B shows a front view of the magnetic sensor 100d, and FIG. 19C shows a side view of the magnetic sensor 100d. In FIG. 19, some configurations are omitted or simplified.

The magnetic sensor 100d includes a first reluctance group 121a, a second reluctance group 122b, a detection circuit 10a to 10b die pad 130, a wire 134, a sealing resin 138, a lead 132, a first substrate 201a, a second substrate 201b, and a third. A substrate 201c and a fourth substrate 201d are provided. As described above, the sinusoidal first magnetic resistance 12a to the sinusoidal fourth magnetic resistance 12d are collectively referred to as "
"1st reluctance group 121a (or 1st reluctance group 122a)", cosine 1st reluctance 12e to cosine 4th reluctance 12h are collectively referred to as "2nd reluctance group 121b (or 2nd reluctance group 122b)". Is written.

A first magnetoresistive group 121a is provided on the first substrate 201a.

A second magnetoresistive group 121b is provided on the second substrate 201b. The second substrate 201b has a first portion 201b1 that is thicker than the first substrate 201a, and a second portion 201b2 that extends from this thick portion and overlaps the first substrate 201a. The second magnetoresistive group 121b is provided in the overlapping second portion 201b2.

A first magnetoresistive group 122a is provided on the third substrate 201c. The third substrate 201c has a first portion 201c1 that is thicker than the second substrate 201b, and a second portion 201c2 that extends from this thick portion and overlaps the second substrate 201b. The first magnetoresistive group 122a is provided in the overlapping second portion 201c2.

A second magnetoresistive group 122b is provided on the fourth substrate 201d. The fourth substrate 201d has a first portion 201d1 that is thicker than the fourth substrate 201d, and a second portion 201d2 that extends from this thick portion and overlaps the third substrate 201c. The second magnetoresistive group 122b is provided in the overlapping second portion 201d2.

The first substrate 201a and the second substrate 201b are arranged along the Y axis (second axis). The third substrate 201c and the fourth substrate 201d are arranged along the X axis (first axis). The X-axis and the Y-axis are orthogonal to each other. As a result, at least a part of each substrate is exposed in a top view, so that an electrode 203 for electrically connecting each substrate and the detection circuit 10a (10b) can be provided. In another expression, since at least a part of each substrate is exposed in a top view, an electrode 203 for electrically connecting each substrate and the detection circuit 10a (10b) can be provided.

The second substrate 201b, the third substrate 201c, and the fourth substrate 201d are respectively placed on the mounting substrate. In the present embodiment, the mounting board is a circuit board provided with the detection circuits 10a and 10b. The first portion 201b1 of the second substrate 201b, the first portion 201c1 of the third substrate 201c, and the first portion 201d1 of the fourth substrate 201d each have a portion inclined at a predetermined angle θ with respect to the mounting substrate. Here, θ is 45 to 55 degrees.

The first substrate 201a, the second portion 201b2 of the second substrate 201b, the second portion 201c2 of the third substrate 201c, and the second portion 201d2 of the fourth substrate 201d have substantially the same thickness.

The second portion 201b2 of the second substrate 201b, the second portion 201c2 of the third substrate 201c, and the second portion 201d2 portion of the fourth substrate 201d are formed of an alkaline wet anisotropic etching solution (for example, KOH (potassium hydroxide aqueous solution)). It can be formed by removing a part of the silicon substrate by silicon anisotropic etching using TMAH (tetramethylammonium hydroxide aqueous solution) or the like.

The centers of the first reluctance group 121a and the second reluctance group 122b substantially coincide with each other in top view. In other words, at least a part of the first reluctance group 121a and the second reluctance group 122b overlap in the top view (at least a part overlaps in the top view). With this configuration, the center positions of the first reluctance group 121a and the second reluctance group 121b are substantially the same, so that the Sin signal output by the first reluctance group 121a and the COS signal output by the second reluctance group 121b The phase shift can be suppressed during. Therefore, the angle error of 100d of the magnetic sensor is reduced. Further, the phase shift between the angular signal output by the first reluctance group 121a and the second reluctance group 121b and the angular signal output by the first reluctance group 122a and the second magnetoresistive group 122b can be suppressed. Therefore, the redundancy of the magnetic sensor 100d is improved.

Up to this point, it has been explained that the magnetic sensor of the present embodiment can detect an angle, but the present invention is not limited to this. For example, the linear displacement of an object can be detected. This point will be described in detail.

20 and 21 are diagrams for explaining the detection operation when the linear displacement of an object is detected by using the magnetic sensor of the present embodiment. FIG. 20 shows a case where there is a magnet for detecting linear displacement on the left side of the magnetic sensor 100, and FIG. 21 shows a case where there is a magnet for detecting linear displacement on the right side of the magnetic sensor 100.

The operation in FIG. 20 will be described.
When the magnet moves + Amm in the displacement axis direction, a magnetic vector angle of -90 deg is input to the magnetic sensor 100, and conversely, when the magnet moves -A mm in the displacement axis direction, a magnetic vector angle of + 90 deg is input to the magnetic sensor 100. .. The magnetic vector angle input to the magnetic sensor 100 due to such axial movement has a relationship between the displacement position of the magnet and the magnetic vector as shown in FIG. 20 (b). The output of the magnetic sensor 100 due to the movement of the magnet is obtained by calculating the outputs of the first circuit block and the second circuit block (ARCTAN) so that the vector angle is relative to the displacement position of the magnet as shown in FIG. 20 (c). It is possible to obtain a substantially linear output.

In the operation in FIG. 21, when the magnet moves + Amm in the displacement axis direction, a magnetic vector angle of +90 deg is input to the magnetic sensor 100, and conversely, when the magnet moves −A mm in the displacement axis direction, the magnetic vector of −90 deg with respect to the magnetic sensor 100. The corner is entered. The magnetic vector angle input to the magnetic sensor 100 due to such axial movement has a relationship between the displacement position of the magnet and the magnetic vector as shown in FIG. 21 (b). The output of the magnetic sensor 100 due to the movement of the magnet is obtained by calculating the outputs of the first circuit block and the second circuit block (ARCTAN) so that the vector angle is relative to the displacement position of the magnet as shown in FIG. 21 (c). It is possible to obtain a substantially linear output. Therefore, in the arrangement of FIG. 20 and the arrangement of FIG. 21, the characteristic that the output change of the magnetic sensor 100 is reversed can be obtained.

FIG. 22 is a schematic view of the detection device 230 using the magnetic sensor 100 of the present embodiment. It includes a detection device 230, a case 231 and a guide 232, a magnet to be detected 233, a shaft 234 (the shaft 234 may also be described as a shift lever), and a magnetic sensor 100.

The case 231 has a slit 236 having a predetermined shape.

The slit 236 has a portion along a straight line L231 (the straight line L231 can be described as a first straight line) and a straight line L232 (the straight line L232 can be described as a second straight line). The straight line L231 and the straight line L232 are parallel to each other. In FIG. 22, the slit 236 is H-shaped. A guide 232 is provided on the inner wall of the slit 236. The "guide" can be described as a "dent".

The detection target magnet 233 is arranged so that the slit 236 can be moved along the guide 232. In other words, the magnet to be detected 233 can move along the straight line L232 and the straight line L231. Further, the straight line L232 and the straight line L231 can also be described as the moving locus of the detection target magnet 233. Further, such a moving locus of the straight line L232, the straight line L231, or the magnet to be detected 233 can be described as a "detection lane" (or simply a "lane". Using the description of "lane", , Case 231 can be described as having first and second detection lanes parallel to each other.

A part of the detection target magnet 233 may be fitted into the guide 232, or the detection target magnet 233 may be covered with a resin or the like so that a part of the resin is fitted into the guide 232. Alternatively, the shaft 234 may be configured as a lever mechanism, and the detection target magnet 233 may be configured to move by a link mechanism connected to the lever mechanism.

The shaft 234 is connected to the detection target magnet 233, and the detection target magnet 233 moves along the guide 232 by being operated by the user.

The magnetic sensor 100 is attached to the case 231 and is arranged between the straight line L231 and the straight line L232, and detects the linear displacement of the detection target magnet 233 by the operation described with reference to FIGS. 20 and 21.

FIG. 23 is a view of a part of FIG. 22 viewed from above. In FIG. 23, a configuration unnecessary for explanation is omitted. Further, a straight line passing between the straight line L231 and the straight line L232 is described as the straight line L241. Here, the straight line L241 may be described as a straight line parallel to the straight line L231 and at an equal distance from the straight line L231 and the straight line L232.

In the detection device 230, the first magnetic resistance group 12i and the second magnetic resistance group 12j are provided at positions sandwiching the straight line L241. Alternatively, in another expression, the magnetoresistive element 12 is provided at a position where the straight line L241 passes. On the other hand, the first Hall element 40a and the second Hall element 40b are provided at positions where the straight line L241 does not pass. Alternatively, in another expression, the first Hall element 40a and the second Hall element 40b are provided at a certain distance from the straight line L241.

With this configuration, with respect to the magnetoresistive element, regardless of whether the magnet to be detected 233 is on the straight line L231 or the straight line L232, the distance between the substantially center of each magnetic resistance and each straight line is the same, so that each magnetic resistance The magnitude of the signal output from is almost constant. For example, the magnitude of the signal output from each reluctance is the same when the detection target magnet 233 in FIG. 23 is at point A and when it is at point C. That is, the position of the detection target magnet 233 can be detected with high accuracy regardless of the left or right direction of the detection target magnet 233.

On the other hand, with respect to each Hall element, the detection target magnet 233 is moving on the straight line L231 more than when the detection target magnet 233 is moving on the straight line L232. It passes through positions close to the first Hall element 40a and the second Hall element 40b. Here, the Hall element outputs a large signal having a large magnetic field strength given from the outside. Therefore, the signal output by each Hall element when the detection target magnet 233 is moving on the straight line L231 is more than the signal output by each Hall element when the detection target magnet 233 is moving on the straight line L232. Will also grow.

Therefore, for example, by performing a threshold value determination on the signal output by each Hall element, it is possible to determine in which direction the detection target magnet 233 is located on the left or right side of the magnetic sensor 100. In another expression, it is possible to determine whether the detection target magnet 233 is on the left or right side of the magnetic sensor 100.

The magnetic sensor 100 described with reference to FIG. 22 can be expressed as follows. The magnetic sensor 100 includes a detection circuit into which signals from the magnetoresistive element and the Hall element are input. Here, this detection circuit is an output terminal that performs at least one process selected from amplification, AD conversion, offset correction, and temperature special correction on the signal input from the magnetoresistive element and outputs it as an output signal to the outside. (VOUT in FIG. 32). Further, an interrupt output terminal (IN in FIG. 32) that outputs a first interrupt signal when the signal input from the Hall element is larger than a predetermined threshold value.
T). Here, the first interrupt signal is a signal indicating that the detection target magnet 233 is located away from the magnetic sensor 100 in the first direction.

Further, when the signal input from the Hall element is smaller than the predetermined threshold value, the second interrupt signal may be output. The second interrupt signal is a signal indicating that the detection target magnet 233 is located away from the magnetic sensor 100 in the second direction opposite to the first direction.

Further, as shown in FIG. 24, the first and second interrupt signals are generated by the interrupt generator 80e provided in the detection circuit 10. The interrupt generator 80e receives a signal from each Hall element from the arithmetic circuit 70, and performs a threshold value determination on this signal to generate first and second interrupt signals. The "interrupt generator 80e" may be described as an "interrupt generator".

By the way, in FIG. 13, the magnetic resistance element 122 is arranged on the magnetic resistance element 121 (the center of the magnetic resistance element 121 and the center of the magnetic resistance element 122 are arranged so as to substantially coincide with each other). Although 100b has been described, the configuration in which the center of the magnetoresistive element 121 and the center of the magnetoresistive element 122 can be substantially aligned is not limited to this.

26 to 32 show another magnetic sensor 100e that can be employed to substantially align the center of the magnetoresistive element 121 with the center of the magnetoresistive element 122. Here, in FIGS. 25 to 31, a method of manufacturing the magnetic sensor 100e will be described. FIG. 32 is a perspective view of the magnetic sensor 100e.

First, as shown in FIG. 25, the die pads 130a and the die pads 130b of the magnetic sensor 100e are connected by a connecting portion 251.

Next, as shown in FIG. 26, the detection circuit 10a is arranged on the die pad 130a. The detection circuit 10b is arranged on the die pad 130b.

Next, as shown in FIG. 27, the magnetoresistive element 121 is arranged on the detection circuit 10a. The magnetoresistive element 122 is arranged on the detection circuit 10b.

Next, as shown in FIG. 28, a wire is connected between the detection circuit 10a and the magnetoresistive element 121, the detection circuit 10a and the lead 132a, the detection circuit 10b and the magnetoresistive element 122, and the detection circuit 10b and the lead 132b, respectively. Connect electrically at 134.

Next, as shown in FIG. 29, the magnetoresistive elements 121, 122 and the like are resin-molded with the sealing resin 138.

Next, as shown in FIG. 30, a part of the tie bar 291 (Tie bar 291) is cut off, and then the leads 132a and 132b are bent.

Next, as shown in FIG. 31, the remaining tie bar 291 (Tie bar 291) is separated and the connecting portion 251 is bent to obtain the magnetic sensor 100e in FIG. 32.

With this structure, the center of the magnetoresistive element 121 and the center of the magnetoresistive element 122 can be brought close to each other with high accuracy, and the signals obtained from the magnetoresistive element 121 and the magnetoresistive element 122 can be made substantially the same, which is preferable.

Since the magnetic sensor 100b is formed through the manufacturing process described above, it has the following features.

The lead 132a electrically connected to the detection circuit 10a is drawn from the first surface 321 of the sealing resin 138, and the lead 132b electrically connected to the detection circuit 10b is the first surface 321 of the sealing resin 138. It is pulled out from the second surface 323 facing the above. Here, the lead 132a connected to the detection circuit 10a is pulled out from the bottom surface of the sealing resin 138 at a lower position than the lead 132b connected to the detection circuit 10b. In another expression, the lead 132a connected to the detection circuit 10a and the lead 132b connected to the detection circuit 10b are drawn out from the bottom surface (or top surface) of the sealing resin 138 at different heights. In addition, in FIG. 32, this difference in height is described as "W1".

The connecting portion 251 is drawn from a third surface 325 perpendicular to the first surface 321 and the second surface 323 and has an arch-shaped shape. The shape of the connecting portion 251 is not limited to the arch shape. For example, when a part of the connecting portion 251 is cut after being bent, the shape of the arch is interrupted in the middle (the shape in which the zenith portion of the arch is missing). ) Can be the case. That is, the connecting portion 251 can be expressed as including a portion drawn from at least two positions of the third surface 325. Further, under the arch formed by the connecting portion 251 (in another expression, between two points drawn from the third surface 325 of the connecting portion 251), as shown by the alternate long and short dash line L1 in FIG. 32, the sealing portion 251 is sealed. Boundaries may remain in the resin 138. The boundary is a trace of the sealing resin 138 that seals the magnetoresistive element 121 and the sealing resin 138 that seals the magnetoresistive element 122, which are described with reference to FIG. 31. Here, the "boundary" may mean a line remaining on the resin and / or a state in which a gap is formed in a part of the resin. Also, the position of the "boundary" can be described as being between the die pads 130a and the die pads 130b.

A support portion 281 that connects the die pads 130a and 130b to the tie bar 291 is pulled out from the fourth surface 327 facing the third surface 325 from which the connecting portion 251 is pulled out.

In the detailed description of the examples related to FIGS. 25 to 30, the magnetoresistive elements (121, 122) are arranged on the detection circuits (10a, 10b) arranged on the die pad 130, but the die pad 130 The detection circuit (10a, 10b) may be arranged on the magnetoresistive element (121, 122) arranged above. In this configuration, when the magnetoresistive element 121 and the magnetoresistive element 122 are close to each other, the detection magnetic field input to the magnetoresistive element is approximated, which has the effect of further enhancing the consistency of the output signals.

By the way, although the detection device 230 using the magnetic sensor 100 of the present embodiment has been described with reference to FIG. 22, the configuration of the detection device is not limited to this.

FIG. 33 is a perspective view of another (position) detection device 260 of the present embodiment. FIG. 34A is a top view of a part of the detection device 260. In FIG. 34A, configurations unnecessary for the description are omitted as appropriate.

The detection device 260 includes a case 261, a guide 262, a link mechanism 263, a shaft 264 (the shaft 264 may also be described as a shift lever), and a magnetic sensor 100.

The case 261 has a slit 266 having a predetermined shape.

The slit 266 has a portion along a straight line L261 (the straight line L261 can be described as the first straight line) and a straight line L262 (the straight line L262 can be described as the second straight line). The straight line L261 and the straight line L262 are parallel to each other. In FIG. 33, the slit 266 is H-shaped. A guide 262 is provided on the inner wall of the slit 266. The "guide" can be described as a "dent".

The shaft 264 is connected to the link mechanism 263. When the user operates the shaft 234, the link mechanism 263 (more accurately, a part of the members constituting the link mechanism 263) moves along the guide 262.

The link mechanism 263 is connected to a support portion 263a connected to the shaft 264, a first movable body 263b connected to the support portion 263a, a belt 263c connected to the first movable body 263b, and a belt 263c. The two movable body 263d and the detection target magnet 268 connected to the second movable body 263d are provided.

The support portion 263a is arranged so that the slit 266 can be moved along the guide 262. In other words, the support portion 263a is movable along the straight line L262 and the straight line L261. Further, the straight line L262 and the straight line L261 can also be described as the moving locus of the support portion 263a. Further, such a moving locus of the straight line L262, the straight line L261, or the support portion 263a can be described as a "detection lane" (or simply a "lane". Using the description of the "lane", a case 261 can be described as having first and second detection lanes parallel to each other.

The first movable body 263b is configured to convert the vertical movement of the support portion 263a into a rotational movement. Further, it has a trapezoidal shape in which the rotation amount of the first movable body 263b changes by moving left and right, and the inner peripheral side of the cross section on the support portion 263a side is wide and the outer peripheral side is narrow.

The belt 263c is composed of a belt that connects the first movable body 263b and the second movable body 263d and transmits the rotational movement of the first movable body 263b to the second movable body 263d.

The second movable body 263d has a cylindrical shape and is configured to rotate by receiving the power transmission of the belt 263c. Further, by connecting the detection target magnet 268, the magnetic sensor 100 is given a change in the magnetic field of the detection target magnet 268. In this way, the link mechanism 263 is coupled to the shaft 264 (shift lever) so that the amount of rotation of the second movable body changes as the shaft 264 moves left and right. As a result, there is a difference in the rotation angle of the magnet between the B position and the D position. As a result, the position determination from the A position to the D position can be performed by one magnetic sensor 100.

In addition, such a link mechanism 263 may be described as a "speed change pulley".

When such a link mechanism 263 is used, the Hall element of the magnetic sensor 100 (and the configuration of the circuit used for detecting the output from the Hall element) is not indispensable.

FIG. 34B is a perspective view of another (position) detection device 290 of the present embodiment. FIG. 34C is a top view of a part of the detection device 290. In FIG. 34C, configurations unnecessary for the description are omitted as appropriate.

The detection device 290 includes a case 261, a guide 262, a link mechanism 263, a shaft 264 (the shaft 264 may also be described as a shift lever), and a magnetic sensor 100.

The case 261 has a slit 266 having a predetermined shape.

The slit 266 has a portion along a straight line L261 (the straight line L261 can be described as the first straight line) and a straight line L262 (the straight line L262 can be described as the second straight line). The straight line L261 and the straight line L262 are parallel to each other. In FIG. 33, the slit 266 is H-shaped. A guide 262 is provided on the inner wall of the slit 266. The "guide" can be described as a "dent".

The shaft 264 is connected to the link mechanism 263. When the user operates the shaft 264, the link mechanism 263 (more accurately, a part of the members constituting the link mechanism 263) moves along the guide 262.

The link mechanism 263 includes a support portion 263a, a shaft 272 interlocking with the support portion 263a, a gear 270 interlocking with the shaft 272, and a detection target magnet 268 supported by the gear 270.

The support portion 263a is arranged so that the slit 266 can be moved along the shaft 272. In other words, the support portion 263a is movable along the straight line L262 and the straight line L261. Further, the straight line L262 and the straight line L261 can also be described as the moving locus of the support portion 263a. Further, such a moving locus of the straight line L262, the straight line L261, or the support portion 263a can be described as a "detection lane" (or simply a "lane". Using the description of the "lane", a case 261 can be described as having first and second detection lanes parallel to each other.

The gear 270 moves in the direction indicated by the arrow A1 in the drawing in conjunction with the movement of the support portion 263a from the neutral side C to the home side A. Due to this movement, the distance between the gear 270 (detection target magnet 268) of the magnetic sensor 100 on the home side or the distance between the gear 270 (detection target magnet 268) of the magnetic sensor 100 on the neutral side changes. Further, the gear 270 rotates in conjunction with the shaft 272. Specifically, the shaft 272 moves along the direction of the arrow A2 in the drawing due to the movement of the support portion 263a between AB or the movement of the support portion 263a between EDs. The gear 270 rotates in conjunction with the movement of the shaft 272.

The mechanism for detecting the rotation of the gear 270 (detection target magnet 268) with the magnetic sensor 100 is the same as that of the rotation detection device 150b of FIG. 2B. Therefore, it can be stated that the detection device 290 includes the rotation detection device 150b of FIG. 2B.

Table 1 shows the output of the magnetic sensor 100 included in the detection device 290 for each position of the support portion 263a.

Using the output of the Hall element of the magnetic sensor 100, it is possible to determine whether the support portion 263a (or the shaft 264) is on the home side or the support portion 263a (or the shaft 264) is on the neutral side. Specifically, when the support portion 263a is on the home side, the distance between the magnetic sensor 100 on the home side and the gear 270 (magnet to be detected 268) is small, so that the output of the Hall element included in the magnetic sensor 100 on the home side is small. Becomes High. Therefore, when the output of the Hall element is High, the position of the support portion 263a (shaft 264) can be specified to be any of AB. At this time, further, by using the output of the magnetic sensor 100 on the home side, it is possible to specify which of the AB the support portion 263a (shaft 264) is located on.

On the other hand, when the support portion 263a is on the neutral side, the distance between the magnetic sensor 100 on the home side and the gear 270 (magnet to be detected 268) becomes large, so that the output of the Hall element included in the magnetic sensor 100 on the home side is Low. become. Therefore, when the output of the Hall element included in the magnetic sensor 100 on the home side is LoW, the position of the support portion 263a (shaft 264) can be specified as one of the CDEs. At this time, further, by using the output of the magnetic sensor 100 on the neutral side, it is possible to specify which of the CDEs the support portion 263a (shaft 264) is located on.

Further, in the detection device 290, since there is always a 180 degree difference between the output of the magnetic sensor 100 on the home side and the output of the magnetic sensor 100 on the neutral side, whether or not the difference between the two outputs is 180 or not. By monitoring, it is possible to monitor whether or not there is an abnormality in the detection device 290. As a result, the detection device 290 has high reliability.

FIG. 34D is a perspective view of another (position) detection device 292 of the present embodiment. FIG. 34E is a top view of a part of the detection device 292. In FIG. 34D, configurations unnecessary for the description are omitted as appropriate.

The detection device 292 includes a case 261, a guide 262, a link mechanism 263, a shaft 264 (the shaft 264 may also be described as a shift lever), and a magnetic sensor 100.

The case 261 has a slit 266 having a predetermined shape.

The slit 266 has a portion along a straight line L261 (the straight line L261 can be described as the first straight line) and a straight line L262 (the straight line L262 can be described as the second straight line). The straight line L261 and the straight line L262 are parallel to each other. In FIG. 33, the slit 266 is H-shaped. A guide 262 is provided on the inner wall of the slit 266. The "guide" can be described as a "dent".

The shaft 264 is connected to the link mechanism 263. When the user operates the shaft 264, the link mechanism 263 (more accurately, a part of the members constituting the link mechanism 263) moves along the guide 262.

The link mechanism 263 includes a support portion 263a, a shaft 272 interlocking with the support portion 263a, and a detection target magnet 268 supported by the shaft 272.

The support portion 263a is arranged so that the slit 266 can be moved along the shaft 272. In other words, the support portion 263a is movable along the straight line L262 and the straight line L261. Further, the straight line L262 and the straight line L261 can also be described as the moving locus of the support portion 263a. Further, such a moving locus of the straight line L262, the straight line L261, or the support portion 263a can be described as a "detection lane" (or simply a "lane". Using the description of the "lane", a case 261 can be described as having first and second detection lanes parallel to each other.

The shaft 272 moves in the direction indicated by the arrow A1 in the drawing in conjunction with the movement of the support portion 263a from the neutral side to the home side. Due to this movement, the distance between the detection target magnets 268 of the home side magnetic sensor 100 or the detection target magnet 268 of the neutral side magnetic sensor 100 changes.

Further, the detection target magnet 268 rotates in conjunction with the shaft 272. Specifically, since the shaft 272 has a crank shape, the shaft 272 moves along the direction of the arrow A2 in the drawing due to the movement of the support portion 263a between AB or the movement of the support portion 263a between EDs. .. The detection target magnet 268 rotates in conjunction with the movement of the shaft 272.

In the mechanism for detecting the rotation of the detection target magnet 268 with the magnetic sensor 100, the detection target magnets are separated into two, but the basic configuration is the same as that of the rotation detection device 150b of FIG. 2B. By configuring the detection target magnets to be separated from each other, each of the neutral side magnetic sensor 100 and the home side magnetic sensor 100 can be arranged at the center of the detection target magnet 268. As a result, the detection device 292 has high detection accuracy.

Since the output of the magnetic sensor 100 included in the detection device 292 is the same as that shown in Table 1, the position of the support portion 263a (shaft 264) can be specified from the output of the magnetic sensor 100 in the same manner as in the detection device 290.

FIG. 34F is a perspective view of another (position) detection device 296 of the present embodiment. FIG. 34G is a top view of a part of the detection device 296. In FIG. 34F, configurations unnecessary for explanation are omitted as appropriate.

The detection device 296 includes a case 261, a guide 262, a link mechanism 263, a shaft 264 (the shaft 264 may also be described as a shift lever), and a magnetic sensor 100.

The case 261 has a slit 266 having a predetermined shape.

The slit 266 has a portion along a straight line L261 (the straight line L261 can be described as the first straight line) and a straight line L262 (the straight line L262 can be described as the second straight line). The straight line L261 and the straight line L262 are parallel to each other. In FIG. 33, the slit 266 is H-shaped. A guide 262 is provided on the inner wall of the slit 266. The "guide" can be described as a "dent".

The shaft 264 is connected to the link mechanism 263. When the user operates the shaft 234, the link mechanism 263 (more accurately, a part of the members constituting the link mechanism 263) moves along the guide 262.

The link mechanism 263 includes a support portion 263a, a shaft 272 interlocking with the support portion 263a, and a detection target magnet 268 supported by the shaft 272.

The support portion 263a is arranged so that the slit 266 can be moved along the shaft 272. In other words, the support portion 263a is movable along the straight line L262 and the straight line L261. Further, the straight line L262 and the straight line L261 can also be described as the moving locus of the support portion 263a. Further, such a moving locus of the straight line L262, the straight line L261, or the support portion 263a can be described as a "detection lane" (or simply a "lane". Using the description of the "lane", a case 261 can be described as having first and second detection lanes parallel to each other.

The shaft 272 moves in the direction indicated by the arrow A1 in the drawing in conjunction with the movement of the support portion 263a from the neutral side to the home side. Due to this movement, the distance between the detection target magnets 268 of the home side magnetic sensor 100 or the detection target magnet 268 of the neutral side magnetic sensor 100 changes.

Further, the detection target magnet 268 rotates in conjunction with the shaft 272. Specifically, since the shaft 272 has a crank shape, the shaft 272 rotates along the direction of the arrow A2 in the drawing due to the movement of the support portion 263a between AB or the movement of the support portion 263a between EDs. .. The detection target magnet 268 rotates in conjunction with the movement of the shaft 272.

Since the output of the magnetic sensor 100 included in the detection device 292 is the same as that shown in Table 1, the position of the support portion 263a (shaft 264) can be specified from the output of the magnetic sensor 100 in the same manner as in the detection device 290. Further, since the detection device 296 is provided with the magnetic sensor 100 on the home side and the magnetic sensor 100 on the neutral side oppositely via the substrate 274, two magnetic sensors can be detected with only one magnet to be detected 268. Therefore, a small detection device can be provided. In addition, since there is always a 180 degree difference from the magnetic sensor output, it is necessary to monitor whether or not there is an abnormality in the detection device 290 by monitoring whether or not the difference between the two outputs is 180. Can be done. As a result, the detection device 290 has high reliability.

By the way, although the front view of the magnetic sensor has been described with reference to FIGS. 10 and 11, the connection structure of the die pad 130, the detection circuits 10a and 10b, and the magnetoresistive elements 121 and 122 will be described in detail with reference to FIGS. 35 to 40. ..

In the figure, the thickness T1 is the thickness of the first resin 351. The thickness T2 is the thickness of the detection circuits 10a and 10b. The thickness T3 is the thickness of the second resin 352 between the die pad 130 and the detection circuits 10a and 10b. The thickness T4 is the thickness of the magnetoresistive elements 121 and 122. The thickness T5 is the thickness of the second resin 352 between the magnetoresistive element and the third resin 353. The thickness T6 is the thickness of the third resin 353 between the third resin 353 and the sealing resin 138.

FIG. 35 is a front view of another magnetic sensor 100 g of the present embodiment.

The magnetic sensor 100g includes a die pad 130, detection circuits 10a and 10b, magnetoresistive elements 121 and 122, leads 132a and 132b, wires 134 and 134b, a sealing resin 138, a first resin 351 and a second. A resin 352 and a third resin 353 are provided.

The first resin 351 is a material that connects the die pad 130 and the detection circuits 10a and 10b. Specifically, the first resin 351 is a die-bonding material made of an epoxy material. Here, the elastic modulus of the first resin 351 is set to 8 GPa.

The second resin 352 is a material that connects the detection circuits 10a and 10b and the magnetoresistive elements 121 and 122. Specifically, the second resin 352 is a die-bonding material made of a silicon-based material. Here, the elastic modulus of the second resin 352 is set to 5 MPa.

The third resin 353 is a material that connects the magnetoresistive elements 121 and 122 and the sealing resin 138. Specifically, the third resin 353 is a chip coating material. Here, the third resin 353
The elastic modulus of is 20 MPa.

The elastic modulus of the second resin 352 is smaller than the elastic modulus of the first resin 351. The elastic modulus of the third resin 353 is larger than the elastic modulus of the second resin 352.

The thickness T3 is larger than the thickness T1. The thickness T3 is larger than the thickness T5. The thickness T6 is larger than the thickness T5.

The second resin 352 covers the magnetoresistive elements 121 and 122. The end portion E1 of the second resin 352 is in contact with the upper surface of the detection circuit 10b outside the magnetoresistive element 122.

The third resin 353 covers the second resin 352. The end portion E2 of the third resin 353 is in contact with the side surface of the detection circuit 10b.

FIG. 36 is a front view of another magnetic sensor 100h according to the present embodiment. Hereinafter, the difference from the magnetic sensor 100 g of FIG. 35 will be mainly described.

The magnetic sensor 100h includes a die pad 130, detection circuits 10a and 10b, magnetoresistive elements 121 and 122, leads 132a and 132b, wires 134 and 134b, a sealing resin 138, a first resin 351 and a second. A resin 352 and a third resin 353 are provided. The difference from the magnetic sensor 100 g of FIG. 35 will be mainly described.

The second resin 352 covers the lower surfaces and a part of the magnetoresistive elements 121 and 122. The end portion E3 and the end portion E4 of the second resin 352 are in contact with the side surface of the magnetoresistive element 122.

FIG. 37 is a front view of another magnetic sensor 100i according to the present embodiment. Hereinafter, the difference from the magnetic sensor 100 g of FIG. 35 will be mainly described.

The magnetic sensor 100i includes a die pad 130, detection circuits 10a and 10b, magnetoresistive elements 121 and 122, leads 132a and 132b, wires 134 and 134b, a sealing resin 138, a first resin 351 and a second. A resin 352 and a third resin 353 are provided.

The second resin 352 covers the lower surfaces of the magnetoresistive elements 121 and 122. The end portion E3 and the end portion E4 of the second resin 352 are in contact with the side surface of the magnetoresistive element 122.

FIG. 38 is a front view of another magnetic sensor 100j according to the present embodiment. It differs from the magnetic sensor 100g in FIG. 35 in that the insides of the magnetoresistive elements 121 and 122 coincide with the centers of the detection circuits 10a and 10b.

FIG. 39 is a front view of another magnetic sensor 100k according to the present embodiment. It differs from the magnetic sensor 100g in FIG. 35 in that the insides of the magnetoresistive elements 121 and 122 coincide with the centers of the detection circuits 10a and 10b.

FIG. 40 is a front view of another magnetic sensor 100l according to the present embodiment. It differs from the magnetic sensor 100g in FIG. 35 in that the insides of the magnetoresistive elements 121 and 122 coincide with the centers of the detection circuits 10a and 10b.

The configuration shown in FIGS. 35 to 40 has the effect of relaxing the stress applied to the magnetoresistive element during assembly of the magnetic sensor, and when the magnetic sensor is mounted by solder mounting or when an external stress is applied after mounting. It is also possible to relax the stress transmitted to the magnetoresistive element. Also,
Moisture can be prevented from entering the magnetoresistive element from the outside, which also has the effect of increasing the durability of the magnetic sensor. Further, a vibration isolating effect on the magnetoresistive element can be obtained against external vibration.

Although the stress relaxation configuration of the magnetoresistive element is used in the above embodiment, the stress relaxation configuration of the detection circuit may be obtained by exchanging the detection circuit and the magnetoresistive element. Further, in this embodiment, the stress relaxation configuration is shown by the elastic modulus of each resin material, but it is also possible to appropriately configure the thermal conductivity of each resin material and transmit the internal heat generation of the magnetic sensor to the outside. is there.

Since the position detection device of the present invention has high accuracy or high reliability, it is useful as a magnetic sensor used for, for example, detecting the steering angle of a vehicle.

10, 10a, 10b Detection circuit 12 Magnetic resistance element 12a Sine 1st magnetic resistance 12b Sine 2nd magnetic resistance 12c Sine 3rd magnetic resistance 12d Sine 4th magnetic resistance 12e Cosine 1st magnetic resistance 12f Cosine 2nd magnetic resistance 12g Cosine 1st 3 Magnetic resistance 12h Cosine 4th magnetic resistance 12i 1st magnetic resistance group 12j 2nd magnetic resistance group 14a 1st amplifier 14b 2nd amplifier 14c 3rd amplifier 14d 4th amplifier 15 Offset adjustment circuit 16a 1st differential amplifier 16b 2nd Differential amplifier 17 Gain adjustment circuit 18a 1st AD converter 18b 2nd AD converter 40a 1st Hall element 40b 2nd Hall element 42a 1st amplifier 42b 2nd amplifier 44a 1st comparator 44b 2nd comparator 60a 3rd regulator 60b 1st regulator 60c 2nd regulator 70 Calculation circuit 70a Angle detection circuit 70b Rotation speed detection circuit 70c Offset temperature characteristic correction circuit 70d Gain temperature characteristic correction circuit 70e Automatic correction circuit 80a 1st oscillator 80b 2nd oscillator 80c Memory 80d Temperature sensor 80e Interrupt Generator 90 Diagnostic circuit A
91 Diagnostic circuit B
100, 100a, 100b, 100d, 100e, 100g, 100h, 100i, 100j, 100k, 100l, 100m Magnetic sensor 100a1 wiring 100a2 wiring 100a3 wiring 100a4 wiring 100b1 wiring 100b2 wiring 100b3 wiring 100b4 wiring 121, 122, 123, 124 Elements 121a, 122a 1st magnetic resistance group 121b, 122b 2nd magnetic resistance group 126a 1st electrode group 126b 2nd electrode group 127a 3rd electrode group 127b 4th electrode group 130, 130a, 130b Die pad 132, 132a, 132b Lead 134 , 134b Wire 136 Part 138 Encapsulating resin 142 Detection target magnet 142a 1st surface 142b 2nd surface 144 Rotation shaft 146 Bearing 150, 150b Rotation detection device 152 Steering wheel 154 Steering torque 156 Torque sensor 158 Motor 160 ECU
181 Silicon board 183 1st protective layer 184 2nd protective layer 185 MR layer 187 Ti layer 189 Wiring layer 201a 1st board 201b 2nd board 201b1 1st part 201b2 2nd part 201c 3rd board 201c1 1st part 201c2 2nd part 201d 4th board 201d1 1st part 201d2 2nd part 203 Electrode 230, 260, 290, 292, 296 Detection device 231 Case 232 Guide 233 Detection target magnet 234 Shaft 236 Slit 251 Connection part 261 Case 262 Guide 263 Link mechanism 263a Support part 263b 1st movable body 263c Belt 263d 2nd movable body 264 Shaft 266 Slit 268 Detection target magnet 270 Gear 272 Shaft 274 Board 281 Support part 291 Tieber 321 1st surface 323 2nd surface 325 3rd surface 327 4th surface 351 1st Resin 352 2nd resin 353 3rd resin

Claims (12)

The 1st to 16th magnetoresistive elements provided on the substrate and
A detection circuit in which a signal is input from the first to sixteenth magnetoresistive elements is provided.
The first to sixteenth magnetoresistive elements divide the second circle into eight equal parts between the first circle and the second circle whose center coincides with the first circle and is larger than the first circle. Magnetic sensors placed on top of each other in the area. The magnetic sensor according to claim 1, wherein the first to sixteenth magnetoresistive elements have a folded structure, and the unevenness of one magnetoresistive element is inserted into the concave portion of the other magnetoresistive element. The 1st to 16th magnetoresistive elements are
The magnetic sensor according to claim 1, which outputs two sine wave signals and two cosine wave signals. It has a first detection circuit and a second detection circuit in which signals are input from the first to 16th magnetoresistive elements.
The first detection circuit outputs a first angle signal from one of the two sine wave signals and one of the two cosine wave signals.
The magnetic sensor according to claim 3, wherein the second detection circuit outputs a second angle signal from the other of the two sine wave signals and the other of the two cosine wave signals. The magnetic sensor according to claim 1, wherein the substrate is arranged on the first detection circuit and the second detection circuit. The magnetic sensor according to claim 1, wherein the first to sixteen magnetoresistive elements contain nickel and iron. A substrate whose main surface is an XY plane composed of X-axis and Y-axis that are orthogonal to each other,
The 1st to 16th magnetoresistive elements provided on the substrate and
A detection circuit in which a signal is input from the first to sixteenth magnetoresistive elements is provided.
The 1st to 16th magnetoresistive elements are
Between the first circle and the second circle whose center coincides with the first circle and is larger than the first circle, the inclination is 45 n ° with respect to the X axis through the center (where n is 0, 1). Or a magnetic sensor having a set arranged line-symmetrically with respect to the straight line of 2). The magnetic sensor according to claim 7, wherein the first to sixteenth magnetoresistive elements have a folded structure, and the unevenness of one magnetoresistive element is inserted into the concave portion of the other magnetoresistive element. The 1st to 16th magnetoresistive elements are
The magnetic sensor according to claim 7, which outputs two sine wave signals and two cosine wave signals. It has a first detection circuit and a second detection circuit in which signals are input from the first to 16th magnetoresistive elements.
The first detection circuit outputs a first angle signal from one of the two sine wave signals and one of the two cosine wave signals.
The magnetic sensor according to claim 9, wherein the second detection circuit outputs a second angle signal from the other of the two sine wave signals and the other of the two cosine wave signals. The magnetic sensor according to claim 7, wherein the substrate is arranged on the first detection circuit and the second detection circuit. The magnetic sensor according to claim 7, wherein the first to sixteen magnetoresistive elements contain nickel and iron.

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