JP2018146483A - Magnetic sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic sensor capable of improving accuracy or reliability.SOLUTION: A magnetic sensor is configured so as to include: a die pad; a first circuit board provided on the die pad; a first magnetic resistance element which is provided on the first circuit board and electrically connected to the first circuit board; first resin between the die pad and the first circuit board; second resin between the first circuit board and the first magnetic resistance element; third resin covering the second resin; and sealing resin sealing the die pad, the first circuit board and the first magnetic resistance element.SELECTED DRAWING: Figure 35

Description

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

  Conventionally, a magnetic sensor that detects a steering angle even when an ignition switch is off is known. For example, Patent Documents 1 to 3 are known as prior art documents for making such a magnetic sensor.

  Or the magnetic sensor which detects rotation of the object containing a steering angle etc. using a magnetoresistive element is known. For example, Patent Documents 4 to 6 are known as prior art documents for making such a magnetic sensor.

  Alternatively, a magnetic sensor having a magnetic field generating means and diagnosing the sensor based on a magnetic field generated from the magnetic field generating means is known. For example, Patent Documents 7 and 8 are known as prior art documents for making such a magnetic sensor.

  Alternatively, a magnetic sensor combining a magnetoresistive element and a Hall element is known. For example, Patent Documents 9 and 10 are known as prior art documents for making such a magnetic sensor.

  Alternatively, there is known a magnetic sensor that provides two detection systems to improve sensor redundancy. For example, Patent Documents 11, 12, and 13 are known as prior art documents for making such a magnetic sensor.

  Alternatively, a magnetic sensor that detects an external magnetic field using a magnetoresistive film made of a NiFe alloy is known. For example, Patent Documents 14, 15, 16, and 17 are known as prior art documents for making such a magnetic sensor.

  Alternatively, a magnetic sensor is known in which two sensors are stacked in the vertical direction to form one package. For example, Patent Documents 18, 19, 20, 21, and 22 are known as prior art documents for making such a magnetic sensor.

  Alternatively, a position detection device that detects the position of a shift lever using a magnetic sensor is known. For example, Patent Documents 23, 24, and 25 are known as prior art documents for making such a position detection device.

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

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

JP-A-2015-116964 International Publication No. 2014/148087 JP 2002-213944 A JP 2014-209124 A Japanese Patent No. 5708986 JP 2007-155668 A Japanese Patent No. 5620891 JP-A-6-310776 Japanese Patent No. 4138952 Japanese Patent No. 5083281 Japanese Patent No. 3474496 Japanese Patent No. 48633953 Japanese Patent No. 5638900 Japanese Patent Publication No. 4-26227 JP 2004-172430 A Japanese Patent Laying-Open No. 2015-082633 JP2015-108527A Japanese Patent No. 5961777 US Patent Application Publication No. 2015/0198678 US Pat. No. 9,151,809 U.S. Pat. No. 8,841,776 US Pat. No. 7,906,961 JP 2006-234495 A JP 2007-333489 A JP 2005-521597 A Japanese Patent No. 5062450 Japanese Patent No. 5062449 Japanese Patent Laying-Open No. 2015-38507 JP2015-41701A JP 2014-86677 A

  However, the conventional magnetic sensor is not sufficient to meet the demand for high accuracy and high reliability that continues to increase.

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

  In order to solve the above-described object, the present invention provides a die pad, a first circuit board provided on the die pad, a first magnetoresistor provided on the first circuit board and electrically connected to the first circuit board. An element, a first resin between the die pad and the first circuit board, a second resin between the first circuit board and the first magnetoresistive element, a third resin covering the second resin, And a sealing resin for sealing the die pad, the first circuit board, and the first magnetoresistive element.

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

Block diagram of magnetic sensor of embodiment Schematic diagram of a rotation detection device using the magnetic sensor Schematic diagram of another rotation detector using the magnetic sensor Schematic diagram of another magnet provided in the rotation detection device The figure explaining operation of the detection circuit of the magnetic sensor The figure explaining another operation | movement of the detection circuit of the magnetic sensor The figure explaining another operation | movement of the detection circuit of the same magnetic sensor further The figure explaining the method of detecting rotation of the magnetic sensor The figure explaining further another operation | movement of the detection circuit of the magnetic sensor, (a) The flowchart explaining operation | movement of the automatic correction circuit 70e, (b) The conceptual diagram explaining operation | movement of correction | amendment. The block diagram which shows the modification of the magnetic sensor of this Embodiment Top view of magnetoresistive element and detection circuit Front view of magnetic sensor Front view of another magnetic sensor according to the present embodiment Top view of the magnetic sensor Front view of still another magnetic sensor according to the present embodiment Front view of still another magnetic sensor according to the present embodiment FIG. 13 is a perspective view of the magnetic sensor of FIG. 15 is another perspective view of the magnetic sensor of FIG. Front view of the magnetoresistive element of FIG. Sectional view taken along the line PP 'in FIG. Front view of still another magnetic sensor according to the present embodiment The figure explaining operation according to the magnetic sensor of this embodiment The figure explaining operation according to the magnetic sensor of this embodiment The perspective view of the detection apparatus of this Embodiment Top view of the detector Block diagram of the magnetic sensor provided in the detection device The figure explaining the manufacturing method of 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 The perspective view of another detection apparatus of this Embodiment Top view of part of the detector The perspective view of another detection apparatus of this Embodiment. Top view of part of the detector The perspective view of another detection apparatus of this Embodiment. Top view of part of the detector The perspective view of another detection apparatus of this Embodiment. Top view of part of the detector Front view of still another magnetic sensor according to the present embodiment Front view of still another magnetic sensor according to the present embodiment Front view of still another magnetic sensor according to the present embodiment Front view of still another magnetic sensor according to the present embodiment Front view of still another magnetic sensor according to the present embodiment Front view of still another magnetic sensor according to the present embodiment

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

  FIG. 1 is a block diagram of a magnetic sensor according to an 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 sine first magnetoresistive element 12a, a sine second magnetoresistive element 12b, a sine third magnetoresistive element 12c, and a sine fourth magnetoresistive element 12d. Further, the magnetoresistive element 12 includes a cosine first magnetoresistive element 12e, a cosine second magnetoresistive element 12f, a cosine third magnetoresistive element 12g, and a cosine fourth magnetoresistive element 12h. Each magnetoresistive element is a magnetoresistive element including an iron-nickel alloy provided on a substrate such as silicon, and its electric resistance changes in accordance with changes in the direction and magnitude of a magnetic field applied from the outside. .

  The sine first magnetoresistive element 12a to the sine fourth magnetoresistive element 12d constitute a first bridge circuit WB1. That is, the first bridge circuit WB1 includes a circuit in which a sine first magnetoresistive element 12a and a sine third magnetoresistive element 12c are connected in series, a sine second magnetoresistive element 12b, and a sine fourth magnetoresistive element 12d. Are connected in parallel to each other. One end of the first bridge circuit WB1 is connected to the potential VS, and the other end is grounded to the ground (GND in the drawing).

  The cosine first magnetoresistive element 12e to the cosine fourth magnetoresistive element 12h constitute a second bridge circuit WB2. That is, the second bridge circuit WB2 includes a circuit in which a cosine first magnetoresistance element 12e and a cosine third magnetoresistance element 12g are connected in series, a cosine second magnetoresistance element 12f, and a cosine fourth magnetoresistance element 12h. Are connected in parallel to each other. One end of the second bridge circuit WB2 is connected to the potential VC, and the other end is grounded to the ground (GND in the drawing).

  Here, the first bridge circuit WB1 is rotated by 45 ° with respect to the second bridge circuit WB2. In other words, the second bridge circuit WB2 is arranged rotated by 45 ° with respect to the first bridge circuit WB1.

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

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

  The detection circuit 10 receives a + sin signal, a −sin signal, a + cos signal, and a −cos signal, and performs various signal processing such as amplification and AD conversion on the + sin signal, the −sin signal, the + cos signal, and the −cos signal. The structure to perform is provided.

  A signal from each magnetoresistive element can be referred to as a “first rotation signal”.

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

  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 the midpoint potential difference between the + sin signal and the −sin signal, the + cos signal, Each adjustment is made so that the midpoint potential difference between the −cos signals becomes zero.

  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 a double amplitude.

  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 a double amplitude.

  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 set so that the amplitude of the sin signal and the cos signal after differential amplification becomes a predetermined amplitude. Adjust.

  With this configuration, there is no need 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 particularly contributes to circuit miniaturization.

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

  The magnetic sensor 100 correction method according to the present embodiment includes a first step for amplifying the outputs of the bridge circuits wb1 and wb2, a second step for correcting an offset of the outputs of the bridge circuits wb1 and wb2, and an output with the offset corrected. And a fourth step for correcting the gain of the output whose offset is corrected.

The first AD converter 18a performs A / D conversion on the signal from the first differential amplifier 16a at a predetermined sampling period 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 period and outputs it as a cos signal (digital signal).

  The first Hall element 40a is a Hall element having detection sensitivity with respect to a magnetic field perpendicular or parallel to the circuit board on which the detection circuit 10 is provided, and the direction and magnitude of the external magnetic field (rotating magnetic field) described above. Is detected and a detection signal is output.

  The second Hall element 40b is a Hall element having detection sensitivity with respect to a magnetic field in a direction perpendicular 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. A change is detected and a detection signal is output.

  A 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 that is a rectangular wave signal.

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

  Here, the first Hall element 40a is arranged 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). Arranged). Therefore, the first pulse signal (in other words, 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.

  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 an amplifier in the detection circuit 10 that processes signals from the Hall elements.

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

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

  The angle detection circuit 70a may be described 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. A method for measuring the rotational speed will be described later.

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

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

  The first oscillator 80 a 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 to detect the magnetoresistive element 12 and each Hall element.

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

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

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

FIG. 2A (a) is a schematic diagram of a rotation detection device 150 using the magnetic sensor 100.
The rotation detection device 150 includes the 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 diagram illustrating 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 in order to switch the direction of the automobile, 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 electrical 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. The magnetic sensor 100 is attached to the motor 158, and the motor is controlled by detecting the rotation angle of the motor.

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

  The rotation detection device 150 b 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” can be described as “the positive side of the rotation shaft 144 (Z axis in the drawing)”. “Lower side” may be expressed as “the negative side of the rotating shaft 144 (Z axis in the drawing)”.

  The width of the rotating shaft 144 (the width in the direction along the X axis in the drawing) is denoted as D1.

  The detection target magnet 142 has a first surface 142a that is supported by the rotation shaft 144 and is perpendicular to the rotation shaft 144 (Z-axis in the drawing), and a second surface 142b that faces the first surface 142a. The width of the detection target magnet 142 in the direction along the rotation axis 144 (Z axis in the drawing) is expressed 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 an N pole. In another expression, it may be described that “the magnet 142 to be detected 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 the positive side of the X axis and the negative side of the X axis.

  The upper magnetic sensor 100 is provided with a first distance (D1) from the first surface 142a. The upper magnetic sensor 100 is provided with a second space (D2) from the rotation 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 to be spaced apart from the second surface 142b by a first distance (D1). The lower magnetic sensor 100 is provided with a second space (D2) from the rotation 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. Furthermore, 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. The first interval (D1) is smaller than the second interval (D2). As an example, the first distance (D1) is 1 mm, and the second distance (D2) is 5 mm.

  Incidentally, in addition to the detection target magnet 142 generating (that is, the rotating magnetic field to be detected), a noise magnetic field may be applied. An example of the noise magnetic field is a leakage magnetic field from a motor. Thus, when a noise magnetic field is applied to the magnetic sensor, the magnetic sensor detects a combined magnetic field of the rotating magnetic field and the noise magnetic field. For this reason, when the direction of the magnetic field to be detected is different from the direction of the noise magnetic field, an error occurs in the detection angle of the magnetic sensor.

  Here, in the rotation detection device 150b, the noise components included in the output signals of the upper magnetic sensor 100 and the lower magnetic sensor 100 are opposite in sign to the upper magnetic sensor 100. The noise component caused by the noise magnetic field can be canceled by taking a differential output from the magnetic sensor 100 on the side.

The detection target magnet 142 may be divided into two as shown in FIG. 2C. That is, “the first surface 142 a side of the detection target magnet 142 is the S pole. The detection target magnet 14.
Although the second side 142b side of the second side is the N pole, ”the detection target magnet 142 in this sentence includes a configuration as shown in FIG. 2C.

  FIG. 3 is a diagram for explaining the operation of the magnetic sensor 100 provided in the magnetic sensor 100 of the present embodiment. FIG. 3 is a flowchart for explaining an operation in which the magnetic sensor 100 detects the movement of the steering during the ignition on (hereinafter may be referred to as “IGon”).

  First, after the magnetic sensor 100 is activated (S300), the magnetic sensor 100 starts detecting the rotation angle (S302 and S303). And each magnetoresistive element of the magnetic sensor 100 performs the calculation of rotation angle detection (S302). Then, the magnetic sensor 100 performs two detections of quadrant determination and rotation speed detection based on the output of each Hall element (S303). The rotation angle and the number of rotations obtained by the above calculation (calculations of S302 and S303) are transmitted from the magnetic sensor 100 to an external microcomputer or the like.

  FIG. 4 is a diagram for explaining another operation of the magnetic sensor 100 according to the present embodiment. FIG. 4 is a flowchart for explaining an operation in which the magnetic sensor 100 detects the movement of the steering during the ignition-off state (hereinafter, sometimes referred to as “IGoff”).

  First, 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 when the IG is turned off (S401). Then, when this control command signal is input, the magnetic sensor 100 shifts to the intermittent operation mode (in another expression, the low power consumption mode) (S402). 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.) is set to sleep (that is, energization is stopped) (S404). And the magnetic sensor 100 detects only the rotation speed of a to-be-detected member for every fixed time using the output signal of each Hall element (S405). Then, the magnetic sensor 100 holds the rotational 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 when IGon is performed (S408). The magnetic sensor 100 receives the control command signal and shifts to the normal mode (S409). Then, the angle of the member to be detected at that time is detected using the signals of each magnetoresistive element and each Hall element only once during the transition to the normal mode (S410, S411). Then, the detection result and the rotation speed at the start of the intermittent operation mode (that is, the final rotation speed before shifting to the intermittent operation mode) are simultaneously transmitted to an external microcomputer or the like. The term “simultaneously” as used herein is not limited to the meaning that two outputs are output at exactly the same time, but includes a case where the outputs are output at substantially the same time.

  In the intermittent operation mode, the second clock signal generated by the second oscillator 80 b is used for various operations (processing) of the detection circuit 10. This is because the frequency of the second oscillator is determined in accordance with the intermittent operation cycle, so that the efficiency of power consumption and the like is good, and the two oscillators can be used for mutual monitoring (diagnosis) of the oscillators. .

  FIG. 5 is a diagram for explaining still another operation of the detection circuit 10 provided 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 during ignition off.

First, in general, in a magnetoresistive element, a signal having waveforms of Sin2θ and Cos2θ is obtained with respect to the rotation angle θ of the member to be detected. For this reason, a magnetic sensor having only a magnetoresistive element is 180.
(In such a magnetic sensor, for example, 90 degrees and 270 degrees are the same signal and cannot be distinguished).

  On the other hand, generally, in the Hall element, as shown in FIG. 5, a signal having waveforms of Sinθ and Cosθ with respect to the rotation angle θ of the detected member is obtained. For this reason, a magnetic sensor having a Hall element can detect up to 360 degrees.

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

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

  First, a first pulse signal and a second pulse signal, which are signals obtained by pulsing signals from the Hall elements, 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, when the first pulse signal rises and falls, the state of the second pulse signal is confirmed and counted. Hereinafter, a calculation example of the rotation speed will be described.

  When the first pulse signal rises from the state where the second pulse signal rises from 0 when the first pulse signal rises, and when the second pulse signal falls from the high state when the first pulse signal falls When the second pulse signal transitions to a state of 0, “forward rotation + 1 rotation” is detected.

  The second pulse signal is High when the first pulse signal rises, the second pulse signal is 0 when the first pulse signal falls, the second pulse signal is High when the first pulse signal rises, When the state transitions, it is detected that “inversion + 1 rotation”.

  With this configuration, when the rotation angle of the motor that has moved during IGoff is detected, it can be detected with higher accuracy and lower power than in the past when IGon is detected again.

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

  By the way, the arithmetic circuit 70 of the magnetic sensor 100 performs “auto calibration mode (first correction mode or active correction mode)” and “to correct the sin signal and the cos signal output from the magnetoresistive element 12. "Temperature correction mode (second correction mode or passive correction mode)".

  First, the “temperature characteristic correction mode (second correction mode or passive correction mode)” will be described.

  The memory 80c stores a coefficient when the dependency 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 coefficient when the dependence of the gain (that is, amplitude) of the sin signal and the cos signal after A / D conversion on the temperature is approximated by a polynomial function is stored.

  The offset temperature characteristic correction circuit 70c performs arithmetic processing using the temperature information (digital signal) input from the temperature sensor 80d and a coefficient related to the temperature dependence of the offset stored in the memory 80c, thereby obtaining 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 a coefficient related to the temperature dependence of the gain stored in the memory 80c, thereby obtaining a sin signal / cos. Correct 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 correction values used for correcting the offset and gain of the sin signal and the cos signal from the magnetoresistive element 12 each time the member to be detected rotates once. 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 generating / updating a correction value based on a signal from the magnetoresistive element 12 obtained during one rotation of the member to be detected, and obtained during the next one rotation of the member to be detected. The operation of correcting the signal from 12 is an “auto calibration” operation.

  When auto calibration is ON, the maximum value Vmax / minimum value Vmin of the sine signal and cos signal from the magnetoresistive element 12 are always held (peak hold, S703), and the offset is obtained when the rotated member makes one rotation. Calculates (Vmax + Vmin) / 2, and (Vmax−Vmin) for the gain, generates correction values for correcting the offset / gain, and updates them (S705). At the same time, the Vmax · Vmin values are reset to 0 (S706).

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

  Again, the Vmax and Vmin values are kept until the next one rotation is completed, and the same operation is repeated thereafter.

The determination of whether or not the rotation has been made “one rotation” is performed when the angle output value after arctan jumps from 360 degrees to 0 degrees (forward rotation), or jumps from 0 degrees to 360 degrees (inversion). When the forward / reverse direction is different from the previous value, it is not regarded as “one rotation”, and in such a case, the correction value is not updated. More specifically, it is explained as follows:
In the case of the previous forward rotation (arrow 1 in FIG. 7B) and the current forward rotation (arrow 2 in FIG. 7B) as shown in FIG. 7B, the automatic correction circuit 70e is regarded as “one rotation”. Performs the operation of updating the correction value.

  In the case of the previous forward rotation (arrow 2 in FIG. 7B) and the current forward rotation (arrow 3 in FIG. 7B) as in FIG. 7B, it is regarded as “one rotation” and the automatic correction circuit 70e. Performs the operation of updating the correction value.

  Similarly, in the case of previous reversal and current reversal, it is regarded as “one 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 current reverse rotation (arrow 5 in FIG. 7B), such as C in FIG. 7B, the automatic correction circuit 70e is not regarded as “one rotation”. Does not update the correction value.

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

  In the case of previous reversal (arrow 6 in FIG. 7B), such as E in FIG. 7B, and forward rotation this time (arrow 7 in FIG. 7B), the automatic correction circuit 70e is not regarded as “one rotation”. The operation to update the correction value is not performed.

  With this configuration, even when the offset / gain (amplitude) of the sin signal and the cos signal of the magnetic sensor element change with time, the adjustment value is updated one by one, so that the offset / gain (amplitude) is always constant. be able to. At the same time, even when the detected member rotates both in the normal direction and in the reverse direction, the offset can be accurately updated.

  When the “auto calibration mode (first correction mode or active correction mode)” is ON, the “temperature characteristic correction mode (second correction mode or passive correction mode)” is OFF, and “auto calibration is performed. It is preferable to operate so that the “temperature characteristic correction mode (second correction mode or passive correction mode)” is ON when the “mode (first correction mode or active correction mode)” is OFF. In another expression, the magnetic sensor 100 switches between “auto calibration mode (first correction mode or active correction mode)” and “temperature characteristic correction mode (second correction mode or passive correction mode)”. To work. With this configuration, when the auto-calibration mode is on, correction is applied to all changes over time including the temperature characteristics, so that the temperature characteristics correction mode can be turned off. On the other hand, in the auto calibration mode, the correction value is not updated until the rotated member is rotated once, so that the auto calibration is performed in an application that does not rotate once or an application that has a large change in offset / gain value until it rotates once. It is preferable to use the passive correction mode rather than the calibration mode.

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

  In the description of the auto-calibration mode and the temperature characteristic correction mode, the case of correcting the sin signal and cos signal of the magnetoresistive element from the magnetoresistive element has been described, but the present invention is not limited thereto. Any element that reacts to magnetism and outputs a sin signal and a cos signal according to the rotation of the member to be detected may not be a magnetic resistance. That is, the auto calibration mode and the temperature characteristic correction mode can be used for correcting 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 by another expression. Specifically, it can be described as follows. The automatic correction circuit 70e has a normal rotation when the angle signal output from the angle detection circuit 70a changes from 360 degrees to 0 degrees, and an inversion when the angle signal changes from 0 degrees to 360 degrees. Or, when a change from inversion to inversion occurs, generation and / or updating of a correction value is executed.

  It should be noted that the operation of the automatic correction circuit 70e in the auto calibration mode can be expressed by 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 “inverted from normal rotation” or “inverted from normal rotation”. Rotation detection including a second step for detecting, and a third step for stopping the first step when it is detected in this second step that the rotation has been performed in the order of “inversion from normal rotation” or “inversion from inversion”. This is a correction method for the apparatus.

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

  One end of the sine first magnetoresistive element 12a and one end of the sine second magnetoresistive element 12b are connected to the potential Vs.

  One end of the sine third magnetoresistive element 12c and one end of the sine fourth magnetoresistive element 12d are connected to the ground (GND in the drawing).

  The other end of the sine first magnetoresistive element 12a is connected to the detection circuit 10 via a wiring 100a1.

  The other end of the sine second magnetoresistive element 12b is connected to the detection circuit 10 via the wiring 100a2.

  The other end of the sine third magnetoresistive element 12c is connected to the detection circuit 10 via the wiring 100a3.

  The other end of the sine fourth magnetoresistive element 12d is connected to the detection circuit 10 via the wiring 100a4.

  In another expression, the other end of each of the sine first to fourth magnetoresistive elements is connected to the detection circuit 10 via wirings 100a1 to 100a4.

  Inside the detection circuit 10, a connection point A between the other end of the sine first magnetoresistive element 12a and the other end of the sine third magnetoresistive element 12c (in other words, a midpoint constituting the first bridge circuit wb1) A) is formed.

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

  Inside the detection circuit 10, a connection point B between the other end of the sine second magnetoresistive element 12b and the other end of the sine fourth magnetoresistive element 12d (in other words, a midpoint constituting the first bridge circuit wb1) B) is formed.

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

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

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

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

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

  In another expression, the other end of each of the cosine first to fourth magnetoresistive elements 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, a connection point C between the other end of the cosine first magnetoresistive element 12e and the other end of the cosine third magnetoresistive element 12g (in other words, a midpoint constituting the second bridge circuit wb2) C) is formed.

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

  Inside the detection circuit 10, a connection point D between the other end of the cosine second magnetoresistive element 12f and the other end of the cosine fourth magnetoresistive element 12h (in other words, a midpoint constituting the second bridge circuit wb2) D) is formed.

  The signal at the connection point D (middle point 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 detection of disconnection 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 input signals from the magnetoresistive element 12, are in the vicinity of the midpoint potential. As a result, the first amplifier 14a to the fourth amplifier 14d, the first differential amplifier 16a and the first AD converter 18a are output near the middle point. On the other hand, when any one of the wirings 100a1 to a4 and 100b1 to b4 is cut, the ground 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 an abnormality determination, and outputs an abnormal signal. With this configuration, it is possible to detect disconnection of the connecting portion of the magnetoresistive element 12 and the detection circuit 10.

  In addition, it is detected that the output of the first AD converter 18a or the second AD converter 18b is out of the normal operation range (in other expressions, a predetermined range, a predetermined voltage range, etc. can be described), and an abnormality determination is diagnosed. However, the present invention is not limited to this. For example, it is possible to detect that the output of the first differential amplifier 16a or the second differential amplifier is out of the normal operation range, diagnose an abnormality determination, and output an abnormal signal.

In addition, when the structure of FIG. 8 is expressed by another description, it can be described as follows. A first substrate including a bridge circuit (wb1 or wb2) composed of first to fourth magnetoresistive elements (sine first to fourth magnetoresistive elements or cosine first to fourth magnetoresistive elements), and the first to fourth magnetisms A first substrate having a detection circuit 10 connected to the resistance element, and first, first, second, third, and fourth wirings that connect between one end of each of the first, second, third, and fourth magnetoresistance elements and the detection circuit 10 ( 100a1-100a4 or 100b1-100b4). Here, the midpoint of the bridge circuit is provided on the second substrate.

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

  The magnetoresistive element 12 is connected to the third regulator 60a in the detection circuit 10 by the changeover switches 110a and 110b via the current detection resistors 112a and 112b or by direct connection (no resistance). In normal times, the change-over switches 110a and 110b are selected to have a current path directly connected to the third regulator 60a, and the change-over switches 110a and 110b are connected via the resistors 112a and 112b only during the resistance value diagnosis of the magnetoresistive element 12. This 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 the resistance value is abnormal, or if the wires of VS and VC are broken, the amount of current flowing through the resistors 112a and 112b is normally Out of range. The diagnostic circuit B91 determines that an abnormality has occurred due to out of this range, and outputs an abnormality signal. With this configuration, it is possible to detect an abnormal resistance value of the magnetoresistive element 12 and to detect a wire breakage with the VS and VC. A failure can be detected even when the sheet resistance of the magnetoresistive element 12 changes (that is, the resistance of the four magnetoresistive elements constituting the bridge circuit changes simultaneously).

  In addition, after the period during which the current path connected to the third regulator 60a through the resistor 112a is selected (that is, the period during which the diagnosis of the first bridge circuit wb1 is performed), the first path through the resistor 112b. It is preferable to provide a period during which the current path connected to the three regulator 60a is selected (that is, a period during which the diagnosis of the second bridge circuit wb is performed). As a result, since 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, the first circuit without increasing the circuit scale of the diagnostic circuit B91. The first bridge circuit wb1 and the second bridge circuit wb2 can be diagnosed.

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

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

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

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

  In the third step, a potential is supplied via the third current path from the third regulator 60a to the second bridge circuit wb2.

  In the fourth step, a potential is supplied from the third regulator 60a to the second bridge circuit wb2 via the fourth current path (having 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.

  The second and fifth steps and the fourth and sixth steps are preferably performed before and after each other, not simultaneously. As a result, since 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, the first circuit without increasing the circuit scale of the diagnostic circuit B91. The first bridge circuit wb1 and the second bridge circuit wb2 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, a part of the configuration is 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 a circuit board on which the detection circuit 10 is provided. In the following description, the sine first magnetoresistive elements 12a to 12d are collectively referred to as “first magnetoresistive element group 12i”, and the cosine first magnetoresistive elements 12e to 12h are collectively referred to as “second magnetoresistive element group”. 12j "in some cases.

  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.

  The magnetoresistive element 12 and the 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 and makes electrical connection with the outside.

  A straight line L1 in FIG. 9 passes through substantially the center of the sine first magnetoresistive element 12a to sine fourth magnetoresistive element 12d and the cosine first magnetoresistive element 12e to cosine fourth magnetoresistive element 12h. Here, the first Hall element 40a and the second Hall element 40b are provided symmetrically with respect to the straight line L1. More specifically, the first Hall element 40a and the second Hall element 40b are provided with an inclination of 45 ° with respect to the straight line L1. In another expression, the straight line L4 passing through the approximate center of the straight line L3 passing through the approximate center of the first Hall element 40a is a magnetoresistive pattern included in any of the sine first magnetoresistive element 12a to the sine fourth magnetoresistive element 12d. Parallel. A straight line L5 passing through the approximate center of the second hall element 40b is parallel to the magnetoresistive pattern of any one of the sine first magnetoresistive element 12a to the sine fourth magnetoresistive element 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 that easily obtains a magnetic field in a direction parallel to the circuit board. It is preferable to provide near the center of the substrate.

  FIG. 11 is a front view of another magnetic sensor 100a of the present embodiment. FIG. 12 is a top view of the magnetic sensor 100a. In FIG. 12, a part of the configuration is omitted. In the following description, the sine first magnetoresistive element 12 a to the sine fourth magnetoresistive element 12 d included in the magnetoresistive element 121 are collectively referred to as “first magnetoresistive element group 121 a”, and the cosine number included in the magnetoresistive element 121. The first magnetoresistive element 12e to the cosine fourth magnetoresistive element 12h may be collectively referred to as “second magnetoresistive element group 121b”. Similarly, the sine first magnetoresistive element 12a to sine fourth magnetoresistive element 12d included in the magnetoresistive element 122 are collectively referred to as “first magnetoresistive element group 122a”, and the cosine first magnetoresistive element included in the magnetoresistive element 122. 12e to cosine fourth magnetoresistive element 12h may be collectively referred to as “second magnetoresistive element 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 121, 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.

  The magnetoresistive elements 121 and 122 and the 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 and are electrically connected 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 objects with respect to the straight line L1 in FIG. Alternatively, the approximate center of the first magnetoresistive element group 121a, the approximate center of the second magnetoresistive element group 121b, the approximate center of the first magnetoresistive element group 122a, and the approximate center of the second magnetoresistive element group 122b pass through the straight line L2. . By providing the magnetoresistive element 121 and the magnetoresistive element 122 in this manner, the redundancy of the sensor can be improved, and 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, when viewed from above, the end surface of the magnetoresistive element 121 and the end surface (of the first circuit board) of the detection circuit 10a pass through a 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 to coincide with each other. In another expression, when viewed from above, the end face of the magnetoresistive element 122 and the end face (of the second circuit board) of the detection circuit 10b pass through a straight line L4.

Each of the detection circuit 10a and the detection circuit 10b includes an electrode group that is electrically connected to the magnetoresistive element and the lead. Here, the electrode group includes the first electrode group 126a and the second electrode group 12.
6b. The first electrode group 126a and the second electrode group 126b are parallel to the straight line L5 and the straight line L6. In this way, the electrode group (and the wires connected thereto) are kept away from the straight line L5 (that is, the center of each magnetoresistive element). Thereby, it becomes difficult to receive interference from an electrode group (and the wire connected to it), and the precision of a magnetic sensor improves.

  FIG. 13 is a front view of still another magnetic sensor 100b of 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 100 b, the magnetoresistive element 122 is disposed 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. In other words, the center of the magnetoresistive element 121 and the center of the magnetoresistive element 122 pass through the straight line C1. By doing in this way, since the center of the magnetoresistive element 121 and the center of the magnetoresistive element 122 are close, the signal obtained from the magnetoresistive element 121 and the magnetoresistive element 122 can be made substantially the same, which is preferable.

  The magnetic sensor 100b has a portion 136 that does not overlap the magnetoresistive element 122 in a top view, and in another expression, a portion 136 that protrudes from the magnetoresistive element 121. The portion 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 larger than the width of the substrate constituting the second magnetoresistive element 122. A long portion is a protruding portion 136. The portion 136 is a portion for obtaining a region for providing the wire 134b. By providing the portion 136, the centers of the magnetoresistive element 121 and the magnetoresistive element 122 can be made substantially coincident with each other. And the signal obtained from the magnetoresistive element 122 can be made substantially the same, which is preferable. Note that the die pad 130 may be divided as shown in FIG. 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, a part of the configuration is 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 127 a is provided on a portion 136 that protrudes from the first magnetoresistive element 121. The third electrode group 127a is arranged along the straight line L7.

  The fourth electrode group 127 b is provided in 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 the magnetic sensor 100 has been described as being attached to a motor for assisting the steering wheel 152 and 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.

  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 is a top view of the magnetic sensor 100d, FIG. 19B is a front view of the magnetic sensor 100d, and FIG. 19C is a side view of the magnetic sensor 100d.
In FIG. 19, a part of the configuration is omitted or simplified.

  The magnetic sensor 100d includes a first magnetoresistive element group 121a, a second magnetoresistive element group 122b, detection circuits 10a to 10b, a die pad 130, a wire 134, a sealing resin 138, a lead 132, a first substrate 201a, a second substrate 201b, A third substrate 201c and a fourth substrate 201d are provided. As already described, the sine first magnetoresistive element 12a to the sine fourth magnetoresistive element 12d are collectively referred to as “first magnetoresistive element group 121a (or first magnetoresistive element group 122a)”, cosine first The magnetoresistive element 12e to the cosine fourth magnetoresistive element 12h are collectively referred to as “second magnetoresistive element group 121b (or second magnetoresistive element group 122b)”.

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

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

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

  A second magnetoresistive element group 122b is provided on the fourth substrate 201d. The fourth substrate 201d includes a first portion 201d1 that is thicker than the fourth substrate 201d, and a second portion 201d2 that extends from the thick portion and overlaps the third substrate 201c. The second magnetoresistive element 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. Thereby, 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. In other words, 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 on which the detection circuits 10a and 10b are provided. 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 of the fourth substrate 201d are made of an alkaline wet anisotropic etchant (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 (tetramethyl ammonium hydroxide aqueous solution) or the like.

  The centers of the first magnetoresistive element group 121a and the second magnetoresistive element group 122b substantially coincide with each other when viewed from above. In other words, at least a part of the first magnetoresistive element group 121a and the second magnetoresistive element group 122b overlap in a top view (at least a part overlaps in a top view). With this configuration, since the center positions of the first magnetoresistive element group 121a and the second magnetoresistive element group 121b substantially coincide, the Sin signal output from the first magnetoresistive element group 121a and the second magnetoresistive element group 121b output The phase shift can be suppressed between the COS signal and the COS signal. For this reason, the 100d angular error of the magnetic sensor is reduced. Further, the phase shift between the angle signals output from the first magnetoresistive element group 121a and the second magnetoresistive element group 121b and the angle signals output from the first magnetoresistive element group 122a and the second magnetoresistive element group 122b is also generated. Can be suppressed. For this reason, the redundancy of the magnetic sensor 100d is improved.

  Heretofore, it has been described 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 the 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 the object is detected using the magnetic sensor of the present embodiment. FIG. 20 shows the case where there is a magnet whose linear displacement is detected on the left side of the magnetic sensor 100, and FIG. 21 shows the case where there is a magnet whose linear displacement is detected on the right side of the magnetic sensor 100.

The operation in FIG. 20 will be described.
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, 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 by such movement in the axial direction is the relationship between the displacement position of the magnet and the magnetic vector as shown in FIG. The output of the magnetic sensor 100 accompanying the movement of the magnet is calculated (ARCTAN) by calculating the outputs of the first circuit block and the second circuit block, so that the vector angle is relative to the displacement position of the magnet as shown in FIG. A substantially linear output.

  In the operation in FIG. 21, 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, and conversely, when the magnet moves -A mm in the displacement axis direction, the magnetic vector of -90 deg. A corner is entered. The magnetic vector angle input to the magnetic sensor 100 by such an axial movement is the relationship between the displacement position of the magnet and the magnetic vector as shown in FIG. The output of the magnetic sensor 100 accompanying the movement of the magnet is calculated (ARCTAN) by calculating the outputs of the first circuit block and the second circuit block, so that the vector angle is relative to the displacement position of the magnet as shown in FIG. A substantially linear output. Therefore, in the arrangement shown in FIG. 20 and the arrangement shown in FIG.

  FIG. 22 is a schematic diagram of a detection device 230 using the magnetic sensor 100 of the present embodiment. A detection device 230, a case 231, a guide 232, a detection target magnet 233 shaft 234 (the shaft 234 can also be described as a shift lever), and the magnetic sensor 100 are provided.

  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. “Guide” may be written as “dent”.

  The detection target magnet 233 is arranged so as to be able to move the slit 236 along the guide 232. In another expression, the detection target magnet 233 is movable along the straight line L232 and the straight line L231. Moreover, the straight line L232 and the straight line L231 can also be described as a trajectory along which the detection target magnet 233 moves. Further, such a trajectory of movement of the straight line L232, the straight line L231, or the detection target magnet 233 can also be described as “detection lane” (or simply “lane”. When the description of “lane” is used. The 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, and a part of the resin may be fitted into the guide 232. Alternatively, the shaft 234 may be configured as a lever mechanism, and the detection target magnet 233 may be moved 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 when operated by the user.

  The magnetic sensor 100 is attached to the case 231 and is disposed 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.

  FIG. 23 is a view of a part of FIG. 22 as viewed from above. In FIG. 23, configurations unnecessary for description are omitted. A straight line passing through the middle of the straight line L231 and the straight line L232 is represented as a straight line L241. Here, the straight line L241 may be described as a straight line that is parallel to the straight line L231 and is at an equal distance from the straight line L231 and the straight line L232.

  In the detection device 230, the first magnetoresistive element group 12i and the second magnetoresistive element group 12j are provided at a position 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, the distance from the approximate center of each magnetoresistor to each straight line is the same regardless of whether the detection target magnet 233 is on the straight line L231 or the straight line L232. The magnitude of the signal output from is constant. For example, the magnitude of the signal output from each magnetic resistance 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 even when the detection target magnet 233 is separated in either the left or right direction of the magnetic sensor 100.

  On the other hand, for each Hall element, the detection target magnet 233 is more moved when the detection target magnet 233 is moving on the straight line L231 than when the detection target magnet 233 is moving on the straight line L232. It passes through a position 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 applied from the outside. For this reason, the signal output by each Hall element when the detection target magnet 233 is moving on the straight line L231 is based on the signal output by each Hall element when the detection target magnet 233 is moving on the straight line L232. Also grows.

Therefore, for example, by performing threshold determination on the signal output from each Hall element,
It can be determined whether the detection target magnet 233 is away from the left or right direction of the magnetic sensor 100. In another expression, it can be determined whether the detection target magnet 233 is on the left or right of the magnetic sensor 100.

  The magnetic sensor 100 described in FIG. 22 can be expressed as follows. The magnetic sensor 100 includes a detection circuit to which signals from the magnetoresistive element and the Hall element are input. Here, the detection circuit performs at least one process selected from amplification, AD conversion, offset correction, and temperature characteristic correction on the signal input from the magnetoresistive element and outputs the output signal to the outside as an output signal (VOUT in FIG. 32). Further, an interrupt output terminal (INT in FIG. 32) that outputs a first interrupt signal when a signal input from the Hall element is larger than a predetermined threshold value. 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, the second interrupt signal may be output when the signal input from the Hall element is smaller than the predetermined threshold value. 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.

  The first and second interrupt signals are generated by an interrupt generator 80e provided in the detection circuit 10, as shown in FIG. The interrupt generator 80e receives the signal from each Hall element from the arithmetic circuit 70, and determines the threshold value for this signal (?), Thereby generating the first and second interrupt signals. Note that “interrupt generator 80e” may be described as an “interrupt generator”.

  By the way, in FIG. 13, the magnetoresistive element 122 is disposed on the magnetoresistive element 121 (disposed so that the center of the magnetoresistive element 121 and the center of the magnetoresistive element 122 substantially coincide). 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 matched is not limited thereto.

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

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

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

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

  Next, as shown in FIG. 28, 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 are respectively wired. Electrical connection is made at 134.

  Next, as shown in FIG. 29, the magnetoresistive elements 121 and 122 are resin-molded with a 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 cut off and the connecting portion 251 is bent, so that the magnetic sensor 100e of FIG. 32 is obtained.

  This structure is preferable because 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 signals obtained from the magnetoresistive element 121 and the magnetoresistive element 122 can be made substantially the same.

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

  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. Here, the lead 132a connected to the detection circuit 10a is drawn from the bottom surface of the sealing resin 138 at a lower position than the lead 132b connected to the detection circuit 10b. In other words, the lead 132a connected to the detection circuit 10a and the lead 132b connected to the detection circuit 10b are drawn from the bottom surface (or top surface) of the sealing resin 138 at different heights. In FIG. 32, this height difference is indicated as “W1”.

  The connecting portion 251 is drawn from the third surface 325 perpendicular to the first surface 321 and the second surface 323 and has an arch shape. The shape of the connecting portion 251 is not limited to an arch shape. For example, when a part of the connecting portion 251 is bent and then cut, the shape of the arch is interrupted in the middle (the shape in which the zenith portion of the arch is missing). ) Can also occur. That is, the connecting portion 251 can be expressed as including a portion drawn from at least two places of the third surface 325. Further, under the arch formed by the connecting portion 251 (in another expression, between the two places drawn from the third surface 325 of the connecting portion 251), as shown by a one-dot chain line L1 in FIG. A boundary may remain on the resin 138. The boundary is the trace of the sealing resin 138 that seals the magnetoresistive element 121 and the sealing resin 138 that seals the magnetoresistive element 122 described with reference to FIG. 31 remaining. Here, the “boundary” may mean a state where a line is left in the resin and / or a gap is generated in a part of the resin. Further, the position of the “boundary” may be described as being between the die pad 130a and the die pad 130b.

  A support portion 281 for connecting the die pads 130a and 130b to the tie bar 291 is drawn from the fourth surface 327 opposite to the third surface 325 from which the connection portion 251 is drawn.

  25 to 30, the magnetoresistive elements (121, 122) are arranged on the detection circuits (10a, 10b) arranged on the die pad 130. However, the die pad 130 is used. It is good also as a structure which arrange | positions a detection circuit (10a, 10b) on the magnetoresistive element (121,122) arrange | positioned on the top. In this configuration, when the distance between the magnetoresistive element 121 and the magnetoresistive element 122 is close, the detection magnetic field input to the magnetoresistive element is approximated, and the consistency of the output signals is further enhanced.

  By the way, although the detection apparatus 230 using the magnetic sensor 100 of this Embodiment was demonstrated in FIG. 22, the structure of a detection apparatus is not restricted 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. 34, components unnecessary for 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 can also be described as a shift lever), and the 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 a first straight line) and a straight line L262 (the straight line L262 can be described as a 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. “Guide” may be written as “dent”.

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

  The link mechanism 263 includes 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 first portion connected to the belt 263c. A second movable body 263d and a detection target magnet 268 connected to the second movable body 263d.

  The support portion 263 a is disposed so as to be movable along the slit 266 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 a trajectory of movement of the support portion 263a. Further, such a trajectory of movement of the straight line L262, the straight line L261, or the support portion 263a can also be described as “detection lane” (or simply “lane”. When the description of “lane” is used, 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, the first movable body 263b has a trapezoidal shape in which the amount of rotation of the first movable body 263b is changed by moving left and right, and the inner peripheral side on the support portion 263a side of the cross section is wide and the outer peripheral side is narrow.

  The belt 263c is a belt that connects the first movable body 263b and the second movable body 263d and transmits the rotational motion 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 power transmission from the belt 263c. Further, since the detection target magnet 268 is connected, the magnetic field of the detection target magnet 268 is given to the magnetic sensor 100. In this way, the link mechanism 263 is coupled to the shaft 264 (shift lever), and the rotation amount of the second movable body is changed by the left-right movement of the shaft 264. Thereby, a difference is generated in the rotation angle of the magnet between the B position and the D position. As a result, position determination from the A position to the D position can be performed by one magnetic sensor 100.

  Such a link mechanism 263 can be expressed as a “transmission 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 essential.

  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, components unnecessary for 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 can also be described as a shift lever), and the 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 a first straight line) and a straight line L262 (the straight line L262 can be described as a 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. “Guide” may be written as “dent”.

  The shaft 264 is connected to the link mechanism 263. When the user operates the shaft 264, the link mechanism 263 (more precisely, 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 263 a is disposed so as to be movable along the slit 266 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 a trajectory of movement of the support portion 263a. Further, such a trajectory of movement of the straight line L262, the straight line L261, or the support portion 263a can also be described as “detection lane” (or simply “lane”. When the description of “lane” is used, 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. By this movement, the distance between the gear 270 (detection target magnet 268) of the home-side magnetic sensor 100 or the distance between the gear 270 (detection target magnet 268) of the neutral-side magnetic sensor 100 changes. 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 by movement of the support portion 263a between AB or 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) by the magnetic sensor 100 is the same as that of the rotation detection device 150b in FIG. 2B. Therefore, it can be described 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.

  The output of the Hall element of the magnetic sensor 100 can be used 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 home-side magnetic sensor 100 and the gear 270 (detection target magnet 268) is small, so the output of the Hall element included in the home-side magnetic sensor 100 Becomes High. Therefore, when the output of the Hall element is High, the position of the support portion 263a (shaft 264) can be specified as any one of AB. Further, at this time, by using the output of the home-side magnetic sensor 100, it is possible to specify which of the AB the support portion 263a (the shaft 264) is in.

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

  Further, since the detection device 290 always has a difference of 180 degrees between the output of the home-side magnetic sensor 100 and the output of the neutral-side magnetic sensor 100, it is determined whether or not the difference between the two outputs is 180. By monitoring, it is possible to monitor whether or not the detection device 290 is abnormal. Thereby, the detection apparatus 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 part of the detection device 292. In FIG. 34D, components unnecessary for 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 can also be described as a shift lever), and the 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 a first straight line) and a straight line L262 (the straight line L262 can be described as a 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. “Guide” may be written as “dent”.

  The shaft 264 is connected to the link mechanism 263. When the user operates the shaft 264, the link mechanism 263 (more precisely, 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 that works in conjunction with the support portion 263a, and a detection target magnet 268 that is supported by the shaft 272.

  The support portion 263 a is disposed so as to be movable along the slit 266 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 a trajectory of movement of the support portion 263a. Further, such a trajectory of movement of the straight line L262, the straight line L261, or the support portion 263a can also be described as “detection lane” (or simply “lane”. When the description of “lane” is used, 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. By this movement, the distance between the detection target magnets 268 of the home-side magnetic sensor 100 or the distance between the detection target magnets 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 by movement of the support portion 263a between AB or movement of the support portion 263a between EDs. . The detection target magnet 268 rotates in conjunction with the movement of the shaft 272.

  The mechanism for detecting the rotation of the detection target magnet 268 by the magnetic sensor 100 has two detection target magnets, but the basic configuration is the same as the rotation detection device 150b of FIG. 2B. By adopting a configuration in which the detection target magnets are separated from each other, each of the neutral-side magnetic sensor 100 and the home-side magnetic sensor 100 can be disposed at the center of the detection target magnet 268. Thereby, the detection device 292 has high detection accuracy.

  Since the output of the magnetic sensor 100 provided 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 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 part of the detection device 296. In FIG. 34F, components unnecessary for description 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 can also be described as a shift lever), and the 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 a first straight line) and a straight line L262 (the straight line L262 can be described as a 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. “Guide” may be written as “dent”.

  The shaft 264 is connected to the link mechanism 263. When the user operates the shaft 234, the link mechanism 263 (more precisely, 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 that works in conjunction with the support portion 263a, and a detection target magnet 268 that is supported by the shaft 272.

  The support portion 263 a is disposed so as to be movable along the slit 266 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 a trajectory of movement of the support portion 263a. Further, such a trajectory of movement of the straight line L262, the straight line L261, or the support portion 263a can also be described as “detection lane” (or simply “lane”. When the description of “lane” is used, 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. By this movement, the distance between the detection target magnets 268 of the home-side magnetic sensor 100 or the distance between the detection target magnets 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 by movement of the support portion 263a between AB or 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 provided 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 the detection device 290. Furthermore, since the home side magnetic sensor 100 and the neutral side magnetic sensor 100 are provided oppositely via the substrate 274, the detection device 296 can detect two magnetic sensors with only one detection target magnet 268. Therefore, a small detection device can be provided. In addition, since there is always a difference of 180 degrees from the output of the magnetic sensor, it is monitored whether there is an abnormality in the detection device 290 by monitoring whether the difference between the two outputs is 180 or not. Can do. Thereby, the detection apparatus 290 has high reliability.

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

  In the drawing, the thickness T <b> 1 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 100g 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 resin. 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 bond material made of an epoxy material. Here, the elastic modulus of the first resin 351 is 8 GPa.

  The second resin 352 is a material that connects between the detection circuits 10 a and 10 b and the magnetoresistive elements 121 and 122. Specifically, the second resin 352 is a die bond material made of a silicon-based material. Here, the elastic modulus of the second resin 352 is 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 coat material. Here, the elastic modulus of the third resin 353 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. Thickness T3 is larger than thickness T5. Thickness T6 is larger than thickness T5.

  The second resin 352 covers the magnetoresistive elements 121 and 122. The end E1 of the second resin 352 contacts the upper surface of the detection circuit 10b outside the magnetoresistive element 122.

  The third resin 353 covers the second resin 352. The end 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 100g 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 resin. A resin 352 and a third resin 353 are provided. The difference from the magnetic sensor 100g in FIG. 35 will be mainly described.

  The second resin 352 covers the lower surface and part of the magnetoresistive elements 121 and 122. The end E3 and the end 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 of the present embodiment. Hereinafter, the difference from the magnetic sensor 100g 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 resin. 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 E3 and the end 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 of the present embodiment. 35 is different from the magnetic sensor 100g of FIG. 35 in that the inside of the magnetoresistive elements 121 and 122 and the centers of the detection circuits 10a and 10b coincide.

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

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

The structure as shown in FIGS. 35 to 40 reduces the stress applied to the magnetoresistive element when the magnetic sensor is assembled, and when the magnetic sensor is mounted by solder mounting or when external stress after mounting is applied. It is possible to relieve the stress transmitted to the magnetoresistive element. Further, it is possible to prevent moisture from entering the magnetoresistive element from the outside, and there is an effect of improving the durability of the magnetic sensor. Furthermore, a vibration-proofing effect on the magnetoresistive element against external vibration can be obtained.
In the above embodiment, the stress relieving structure of the magnetoresistive element is used. However, the detecting circuit and the magnetoresistive element may be replaced to have a stress relieving structure of the detecting circuit.
Further, in this embodiment, the stress relaxation configuration is shown by the elastic modulus for each resin material, but it is also possible to appropriately configure the thermal conductivity for 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, for example, as a magnetic sensor used for detecting the steering angle of a vehicle.

10, 10a, 10b Detection circuit 12 Magnetoresistive element 12a Sine first magnetoresistive element 12b Sine second magnetoresistive element 12c Sine third magnetoresistive element 12d Sine fourth magnetoresistive element 12e Cosine first magnetoresistive element 12f Cosine second Magnetoresistive element 12g cosine third magnetoresistive element 12h cosine fourth magnetoresistive element 12i first magnetoresistive element group 12j second magnetoresistive element group 14a first amplifier 14b second amplifier 14c third amplifier 14d fourth amplifier 15 offset adjustment Circuit 16a First differential amplifier 16b Second differential amplifier 17 Gain adjustment circuit 18a First AD converter 18b Second AD converter 40a First Hall element 40b Second Hall element 42a First amplifier 42b Second amplifier 44a First comparator 44b Second comparator 60a Third regulator 6 0b first regulator 60c second regulator 70 arithmetic 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 first oscillator 80b second 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 Magnetic sensor 100a1 wiring 100a2 wiring 100a3 wiring 100a4 wiring 100b1 wiring 100b2 wiring 100b3 wiring 100b4 wiring 121, 122 Magnetoresistive element 121a, 122a Magnetoresistive element group 121b, 122b Second magnetoresistive element group 126a First electrode group 126b Second electrode group 127a Third electrode group 127b Fourth electrode group 130, 130a, 130b Die pads 132, 132a, 132b Lead 134, 134b Wire 136 Portion 138 Sealing resin 142 Magnet to be detected 142a First surface 142b Second surface 144 Rotating shaft 146 Bearing 150, 150b Rotation detecting device 152 Steering wheel Eel 154 Steering torque 156 Torque sensor 158 Motor 160 ECU
201a First substrate 201b Second substrate 201b1 First portion 201b2 Second portion 201c Third substrate 201c1 First portion 201c2 Second portion 201d Fourth substrate 201d1 First portion 201d2 Second portion 203 Electrodes 230, 260, 290, 292, 296 Detection device 231 Case 232 Guide 233 Magnet to be detected 234 Shaft 236 Slit 251 Connection portion 261 Case 262 Guide 263 Link mechanism 263a Support portion 263b First movable body 263c Belt 263d Second movable body 264 Shaft 266 Slit 268 Detection target magnet 270 Gear 272 Shaft 274 Substrate 281 Support part 291 Tie bar 321 First surface 323 Second surface 325 Third surface 327 Fourth surface 351 First resin 352 Second resin 353 Third resin

Claims (7)

Die pad,
A first circuit board provided on the die pad;
A first magnetoresistive element provided on the first circuit board and electrically connected to the first circuit board;
A first resin between the die pad and the first circuit board;
A second resin between the first circuit board and the first magnetoresistive element;
A third resin covering the second resin;
A sealing resin that seals the die pad, the first circuit board, the first magnetoresistive element, and the third resin;
A magnetic sensor wherein at least a part of a side surface of the first magnetoresistive element is covered with the second resin in a cross section. 2. The magnetic sensor according to claim 1, wherein a thickness of a portion of the second resin disposed on an upper surface of the magnetoresistive element is smaller than a thickness of a portion of the second resin disposed on a bottom surface of the magnetoresistive element. 2. The magnetic sensor according to claim 1, wherein a thickness of a portion of the third resin disposed on an upper surface of the second resin is greater than a thickness of a portion of the second resin disposed on an upper surface of the magnetoresistive element. . The thickness of the portion of the second resin disposed on the bottom surface of the magnetoresistive element is greater than the thickness of the portion of the first resin disposed on the bottom surface of the first circuit board,
2. The magnetic sensor according to claim 1, wherein a thickness of a portion of the third resin disposed on an upper surface of the second resin is greater than a thickness of a portion of the second resin disposed on a bottom surface of the magnetoresistive element. The magnetic sensor according to claim 1, wherein an upper surface of the magnetoresistive element is covered with the second resin. 2. The magnetic sensor according to claim 1, wherein an elastic modulus of the second resin is smaller than an elastic modulus of the first resin, and an elastic modulus of the third resin is larger than an elastic modulus of the second resin. The magnetic sensor according to claim 1, wherein an end portion of the third resin is in contact with a side surface of the first circuit board in a cross section.