JP6400533B2 - Detection device and current sensor - Google Patents

Description

  The present invention relates to a detection device and a current sensor.

Conventionally, a magnetic sensor using a Hall element or the like has reduced a DC offset included in an output signal of the Hall element by, for example, a spinning current method (see, for example, Non-Patent Document 1). It has also been known to remove a transient spike signal generated by the spinning current method by using two Hall elements (see, for example, Patent Documents 1 to 3).
Patent Literature 1 JP 2013-178229 A Patent Literature 2 International Publication No. 2014/155908 Patent Literature 3 US Patent Application Publication No. 2003/155912 Non-Patent Literature 1 RS Popovic, “Hall Effect Devices”, Inst of Physics Pub Inc, May 1991

  Such a magnetic sensor can improve characteristics such as sensitivity by using a magnetic converging plate. Moreover, it can also function as a current sensor by installing a magnetic sensor in the vicinity of a current conductor or the like. However, since the input magnetic field is bent by using the magnetic converging plate, the direction of the magnetic field input to each Hall element may differ depending on the position of the Hall element. Similarly, the direction of the magnetic field input to the Hall element may vary depending on the relative arrangement of the Hall element and the current conductor. In such a case, it has been difficult to cancel the offset and reduce the transient spike signal.

  In the first aspect of the present invention, there is provided a detection device for detecting a magnetic field, wherein a first Hall element and a second Hall element to which a magnetic field to be detected is applied in a reverse direction, and a plurality of the first Hall elements have A drive terminal for injecting drive current, a positive measurement terminal, a first switch circuit for switching a negative measurement terminal, and a drive terminal for injecting drive current between a plurality of terminals of the second Hall element; And a second switch circuit that switches between a positive measurement terminal and a negative measurement terminal, wherein the second switch circuit is responsive to the first switch circuit switching the drive terminal of the first Hall element to the positive measurement terminal. Provided is a detection device for switching the drive terminal in the second Hall element to a negative measurement terminal.

  In a second aspect of the present invention, the detection apparatus according to the first aspect and a current conductor extending in a predetermined direction are provided, and the current conductor is between the first Hall element and the second Hall element. A current sensor is provided that extends parallel to a plane including a first Hall element and a second Hall element above or below the point.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

The structural example of the cross section of the 1st magnetic sensor 100 which concerns on this embodiment is shown. The structural example of the upper surface of the 1st magnetic sensor 100 which concerns on this embodiment is shown. The structural example of the cross section of the 2nd magnetic sensor 100 which concerns on this embodiment is shown. The structural example of the upper surface of the 2nd magnetic sensor 100 which concerns on this embodiment is shown. The structural example of the detection apparatus 200 which concerns on this embodiment is shown. The 1st example of the connection of the 1st Hall element 10 concerning this embodiment is shown. The 2nd example of the connection of the 1st Hall element 10 concerning this embodiment is shown. The 3rd example of the connection of the 1st Hall element 10 concerning this embodiment is shown. The 4th example of connection of the 1st hall element 10 concerning this embodiment is shown. The 1st example of the connection of the 2nd Hall element 20 concerning this embodiment is shown. The 2nd example of the connection of the 2nd Hall element 20 concerning this embodiment is shown. The 3rd example of the connection of the 2nd Hall element 20 concerning this embodiment is shown. The 4th example of connection of the 2nd hall element 20 concerning this embodiment is shown. An example of a signal waveform when the drive terminal of the Hall element according to the present embodiment is selected and switched clockwise is shown. An example of a signal waveform when the drive terminal of the Hall element according to the present embodiment is selected and switched to the figure 8 is shown. An example of a signal waveform when the drive terminal of the Hall element according to the present embodiment is switched between two predetermined connections is shown. The structural example of the upper surface of the magnetic sensor 100 at the time of using four Hall elements which concern on this embodiment is shown. The structural example of the detection apparatus 200 at the time of using four Hall elements which concern on this embodiment is shown.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 shows a configuration example of a cross section of the first magnetic sensor 100 according to the present embodiment. FIG. 1 shows an example of a cross-sectional view of the XZ plane of the magnetic sensor 100. The first magnetic sensor 100 outputs a detection signal according to the magnetic field input to the magnetic sensor 100. FIG. 1 shows an example in which a magnetic field in the + Y direction is input to the first magnetic sensor 100. The first magnetic sensor 100 includes a first Hall element 10, a second Hall element 20, a substrate 110, a magnetic convergence plate 120, and a magnetic convergence plate 122.

  The first Hall element 10 and the second Hall element 20 are formed substantially parallel to the XY plane and detect a magnetic field substantially parallel to the Z-axis direction. As an example, the first Hall element 10 and the second Hall element 20 are elements that generate an electromotive force (Hall effect) in the Y-axis direction corresponding to a magnetic field input in the Z-axis direction when a current flows in the X-axis direction. . The first Hall element 10 and the second Hall element 20 may be formed of a semiconductor or the like. FIG. 1 shows an example in which the first Hall element 10 and the second Hall element 20 are arranged substantially parallel to the Y axis.

  The substrate 110 is formed of a semiconductor such as silicon, and may include a semiconductor circuit and a semiconductor element. The substrate 110 may be an IC chip. In this case, the substrate 110 includes a terminal and is electrically connected to an external substrate, a circuit, a wiring, and the like. In FIG. 1, the front and back surfaces of the substrate 110 are arranged substantially parallel to the XY plane, and the axis perpendicular to the XY plane is taken as the Z axis. That is, the X, Y, and Z axes are coordinate systems orthogonal to each other. In the substrate 110, the first Hall element 10 and the second Hall element 20 may be formed inside or on the surface. In this case, the first Hall element 10 and the second Hall element 20 are formed in the manufacturing process of the substrate 110. Is desirable.

  The magnetic converging plate 120 and the magnetic converging plate 122 are converged by changing the direction of the magnetic field to be detected. The magnetic converging plate 120 and the magnetic converging plate 122 are provided substantially in parallel with the substrate 110 and bend the magnetic field input to the magnetic sensor 100. The magnetic flux concentrating plate 120 and the magnetic flux converging plate 122 may be provided on the front surface side or the back surface side of the substrate 110. In addition, the magnetic flux concentrating plate 120 and the magnetic flux converging plate 122 may be provided in contact with the substrate 110, or alternatively, may be provided from the substrate 110 via an insulating layer or the like. FIG. 1 shows an example in which a magnetic converging plate 120 and a magnetic converging plate 122 are provided in contact with the surface side of the substrate 110 and are respectively disposed above the first Hall element 10 and the second Hall element 20.

  The magnetic flux concentrator plate 120 and the magnetic flux concentrator plate 122 are formed of a magnetic material or the like, and for example, a magnetic field in the X-axis direction and / or the Y-axis direction is bent so that a component in the Z-axis direction is generated, and sensitivity in the Z-axis direction is obtained. Are input to the first Hall element 10 and the second Hall element 20, respectively. FIG. 1 shows that the magnetic converging plate 120 and the magnetic converging plate 122 bend the magnetic field input in the + Y direction, and generate a magnetic field in the + Z direction in the first Hall element 10 and a magnetic field in the −Z direction in the second Hall element 20, respectively. An example of making it input is shown.

  FIG. 2 shows a configuration example of the upper surface of the first magnetic sensor 100 according to the present embodiment. That is, FIG. 2 shows the XY plane in FIG. 1, and shows an example of a plan view of the first magnetic sensor 100 viewed from the + Z direction side. In FIG. 2, the magnetic field in the + Z direction that the magnetic converging plate 120 inputs to the first Hall element 10 by bending the magnetic field input in the + Y direction is indicated as + B, and the magnetic field that the magnetic converging plate 122 inputs in the + Y direction is bent. The magnetic field in the −Z direction that is input to the two-hole element 20 is indicated as −B.

  FIG. 3 shows a cross-sectional configuration example of the second magnetic sensor 100 according to the present embodiment. FIG. 3 shows an example of a cross-sectional view of the XZ plane of the magnetic sensor 100. The second magnetic sensor 100 outputs a detection signal according to the magnetic field input to the magnetic sensor 100. The second magnetic sensor 100 functions as a current sensor that detects a magnetic field generated by the flow of current and outputs a detection signal corresponding to the amount of flowing current. Alternatively, the second magnetic sensor 100 may be formed integrally with the current conductor and provided as a current sensor device.

  The current conductor 130 extends in a predetermined direction. Further, the current conductor 130 extends parallel to a plane including the first Hall element 10 and the second Hall element 20 above or below the point between the first Hall element 10 and the second Hall element 20. FIG. 1 shows an example in which the second magnetic sensor 100 detects a Z component of a magnetic field that flows in the + X direction through the current conductor 130 and that is generated counterclockwise around the current in the ZY plane. The second magnetic sensor 100 includes a first hall element 10, a second hall element 20, and a substrate 110.

  The first Hall element 10 and the second Hall element 20 are formed substantially parallel to the XY plane and detect a magnetic field substantially parallel to the Z-axis direction. As an example, the first Hall element 10 and the second Hall element 20 are elements that generate an electromotive force (Hall effect) in the Y-axis direction corresponding to a magnetic field input in the Z-axis direction when a current flows in the X-axis direction. . The first Hall element 10 and the second Hall element 20 may be formed of a semiconductor or the like. FIG. 3 shows an example in which the first Hall element 10 and the second Hall element 20 are arranged substantially parallel to the Y axis and the Z component of the magnetic field generated by the current conductor 130 arranged in the + Z direction is detected.

  The substrate 110 is formed of a semiconductor such as silicon, and may include a semiconductor circuit and a semiconductor element. The substrate 110 may be an IC chip. In this case, the substrate 110 includes a terminal and is electrically connected to an external substrate, a circuit, a wiring, and the like. In FIG. 3, the front and back surfaces of the substrate 110 are arranged substantially parallel to the XY plane, and the axis perpendicular to the XY plane is taken as the Z axis. In the substrate 110, the first Hall element 10 and the second Hall element 20 may be formed inside or on the surface. In this case, the first Hall element 10 and the second Hall element 20 are formed in the manufacturing process of the substrate 110. Is desirable.

  FIG. 4 shows a configuration example of the upper surface of the second magnetic sensor 100 according to the present embodiment. That is, FIG. 2 shows the XY plane in FIG. 3, and shows an example of a plan view of the second magnetic sensor 100 viewed from the + Z direction side. In FIG. 4, among the magnetic fields generated by the current i in the + X direction flowing through the current conductor 130, the + Z direction magnetic field input to the first Hall element 10 is indicated as + B, and the −Z direction magnetic field input to the second Hall element 20 is The magnetic field was indicated as -B.

  The Hall elements included in the first magnetic sensor 100 and the second magnetic sensor 100 according to this embodiment described above output an output signal including an element-specific offset signal. In order to reduce such an offset signal, the spinning current method described in Non-Patent Document 1 is used. The spinning current method switches the direction of the current flowing through the Hall element based on the spinning current clock that repeats the first phase and the second phase, and inverts the polarity of the signal component according to the magnetic field input and the signal component due to the offset.

For example, in the first phase, + the Z direction of the magnetic field input B, + first Hall element is energized in the X direction from the + Y direction side of the terminal generating holes electromotive force signal + V _S (in the -Y direction side A Hall electromotive force signal −V _S is generated from the terminal) and an offset voltage + V _O in the + Y direction is output. In this case, when the first Hall element is energized in the −Y direction in the second phase with respect to the same magnetic field input in the + Z direction, the Hall electromotive force signal + V _S is generated from the terminal on the + X direction side (−X A Hall electromotive force signal −V _S is generated from the terminal on the direction side) and an offset voltage + V _O in the + X direction is output. Therefore, to get the output voltage V _h11 from the Y-axis direction of the terminal of the Hall element in a first phase, by acquiring the output voltage V _h12 from the X-axis direction of the terminal of the Hall element in a second phase, the magnetic field of the Hall element The detection signal of B is expressed as follows:
(Equation 1)
V _h11 = + 2V _S + V _O
V _h12 = -2V _S + V _O

In this way, by switching the energization direction, the sign of the signal component of the Hall electromotive force signal V _S in the detection signal of the Hall element is inverted between the first phase and the second phase as shown in Equation (1). Can be made. That is, in the spinning current method, the Hall electromotive force signal V _S is modulated by a spinning current clock to form a modulation signal, and the offset voltage V _O is used as a DC signal output, so that two signals can be separated in the frequency domain. Ideally, the offset signal can be removed using a filter or the like.

  Such spinning current method reduces the offset signal while transiently generating a spike signal. For example, a Hall element energized to a terminal in the X-axis direction in the first phase is charged when a charge is charged to a capacitive component such as a stray capacitance and an output voltage is output from the terminal in the X-axis direction in the second phase. Discharge the charge.

In this case, as an example, the terminal on the current supply side (on the −X direction side) in the X-axis direction to which the bias + V _B is applied in the first phase is charged with a positive charge in the capacitive component, and the potential of the capacitive component is + V _B. Then, in the second phase, the potential of the terminal is the steady state (that is, the Hall electromotive force signal −) when the charged + charge is discharged and the discharge is finished from the time when the first phase is switched to the second phase. In the period up to the transition to (V _S ), an attenuation curve is drawn from + V _B to −V _S + V _O. Further, a terminal on the current output side (+ X direction side) in the X axis direction to which the bias −V _B is applied in the first phase is charged with −charge, and the potential of the capacitance component becomes −V _B. In the second phase, the potential of the terminal is charged from −V _B during the period from when the charged −charge is discharged until the discharge is completed after the first phase is switched to the second phase. Draw an increasing curve in which the absolute value increases to V _S.

Therefore, in the steady state, the voltage between the terminals in the X-axis direction in the second phase is −2V _S + V _O as in Equation (1), but when the first phase is switched to the second phase. During the period from discharge to completion of discharge, a positive spike signal V _SP (t) is formed as the difference between the attenuation and increase curves at both terminals.

Similarly, at the terminal on the current supply side (+ Y direction side) in the Y-axis direction to which the bias + V _B is applied in the second phase, + charge is charged to the capacitive component, and the potential of the capacitive component becomes + V _B. . Then, in the first phase, the potential of the terminal is the steady state (that is, the Hall electromotive force signal + V) when the charged + charge is discharged and the discharge is finished from the time when the second phase is switched to the first phase. _In the period up to the transition to _S ), an attenuation curve is drawn from + V _B to + V _S + V _O. Further, the terminal on the current output side (on the −Y direction side) to which the bias −V _B is applied in the second phase is charged with −charge, and the potential of the capacitance component becomes −V _B. Then, in the first phase, the potential of the terminal is charged from −V _B during the period from when the charged −charge is discharged until the discharge is completed after switching from the second phase to the first phase. draw a growth curve in which the absolute value is increased to -V _S.

Accordingly, the voltage between the terminals in the X-axis direction in the first phase is + 2V _S + V _O in the steady state as in the formula (1), but from the time when the second phase is switched to the first phase. During the period until the discharge ends, a spike signal V _SP (t) on the + side is formed as the difference between the attenuation / increase curves at both terminals.

That is, the first Hall element outputs a detection signal including a transient spike signal V _SP (t) as shown in the following equation. Note that the spike signal V _SP (t) is a signal that fluctuates with time, and therefore spreads in a wide band in frequency, and cannot be separated in frequency from the Hall electromotive force signal V _S like an offset signal.
(Equation 2)
V _h11 = + 2 V _S + V _O + V _SP (t)
V _h12 = -2V _S + V _O + V _SP (t)

In order to reduce such spike signals, it is known to provide a pair of Hall elements in which energization direction switching directions are opposite to each other, as described in Patent Document 1 and the like. For example, in the first Hall element to which the magnetic field B is applied in the + Z direction, the current flowing direction from the + X direction, the -Y direction, the -X direction, and the + Y direction from the first phase to the fourth phase is clockwise in the XY plane. The detection signal is sequentially changed by approximately 90 degrees, and the detection signal is repeatedly acquired in order using the + Y direction side, the −X direction side, the + Y direction side, and the −X direction side as the positive electrode. Accordingly, signals V _{h11 to} V _h14 acquired from the first phase to the fourth phase of the first Hall element are _expressed by the following equations.
(Equation 3)
V _h11 = + 2 V _S + V _O −V _SP (t)
V _h12 = -2V _S + V _O + V _SP (t)
V _h13 = -2V _S + V _O + V _SP (t)
V _h14 = + 2V _S + V _O −V _SP (t)

The second Hall element to which the magnetic field B in the same direction as the first Hall element is applied is the + X direction, the + Y direction, the -X direction, the -Y direction, and the current flow direction in the first to fourth phases. Are sequentially changed counterclockwise by 90 degrees on the XY plane, and the detection signals are sequentially acquired in the order of the + Y direction side, the + X direction side, the + Y direction side, and the + X direction side as positive terminals. Thereby, signals V _{h21 to} V _h24 acquired from the first phase to the fourth phase of the second Hall element are _expressed by the following equations.
(Equation 4)
V _h21 = + 2 V _S + V _O + V _SP (t)
V _h22 = −2 V _S + V _O −V _SP (t)
V _h23 = −2 V _S + V _O −V _SP (t)
V _h24 = + 2 V _S + V _O + V _SP (t)

By obtaining the sum of signals detected at substantially the same time with respect to the detection signals acquired as shown in (Equation 3) and (Equation 4), the signal shown in the following equation can be acquired. it can.
(Equation 5)
V _h11 + V _h21 = + 4 V _S +2 V _O
V _h12 + V _h22 = -4V _S + 2V _O
V _h13 + V _h23 = -4V _S + 2V _O
V _h14 + V _h24 = + 4 V _S +2 V _O

Thus, by calculating the sum of the detection signals of the first Hall element and the second Hall element, the spike signal can be ideally canceled. Similarly to the equation (1), the signal shown in the equation (5) is caused by the spinning current clock (more precisely, a half of the clock signal) of the hall element detection signals. The power signal V _S is modulated into a DC signal, and the offset voltage V _O is used as a modulation signal output. Therefore, the Hall electromotive force signal V _S and the offset voltage V _O can be separated in the frequency domain, and ideally, the offset signal can be removed using a filter or the like. That is, by using the spinning current method and controlling the energization direction and the signal acquisition direction of the Hall element pair, the spike signal and the offset can be reduced.

  However, the above example is limited to the case where the magnetic field B in the same direction is applied to the first Hall element and the second Hall element. That is, as described with reference to FIGS. 1 to 4, when a magnetic field is applied in the opposite direction to the first Hall element and the second Hall element, the spike signal is emphasized when the above control is executed, In some cases, the detection characteristics of the magnetic field deteriorate. In particular, in continuous-time signal processing in which the detection signal of the magnetic sensor is processed in continuous time, the spike-like signal becomes an error signal as it is, causing performance degradation.

  Therefore, the detection device according to the present embodiment acquires a detection signal when a magnetic field is applied in the opposite direction to the first Hall element and the second Hall element, and reduces the spike signal and the offset. Such a detection apparatus will be described with reference to FIG.

  FIG. 5 shows a configuration example of the detection apparatus 200 according to the present embodiment. The detection device 200 detects a magnetic field input from the outside. The detection device 200 includes a first Hall element 10, a second Hall element 20, a first switch circuit 210, a second switch circuit 212, a first amplification unit 220, a second amplification unit 222, and a first addition. Unit 230, second addition unit 232, amplification unit 240, first switching unit 250, and clock generation unit 260.

  A magnetic field to be detected is applied to the first Hall element 10 and the second Hall element 20 in the opposite directions. That is, the first Hall element 10 and the second Hall element 20 may be substantially the same elements as the first Hall element 10 and the second Hall element 20 included in the magnetic sensor 100 described with reference to FIGS. Each of the first Hall element 10 and the second Hall element 20 has a plurality of terminals. The plurality of terminals included in the first Hall element 10 and the second Hall element 20 may function as any of a drive terminal, a current output terminal, a positive measurement terminal, and a negative measurement terminal, respectively.

  The plurality of terminals of the first Hall element 10 extend from the first Hall element 10 in a plurality of different directions on the first plane. For example, the plurality of terminals included in the first Hall element 10 extend in different directions on the XY plane of the magnetic sensor 100 described with reference to FIGS. In this case, the plurality of terminals included in the first Hall element 10 may be provided in line-symmetric shapes with respect to the X axis and the Y axis.

  The plurality of terminals included in the second Hall element extend in the same direction as the plurality of terminals included in the first Hall element 10 on the first plane. The plurality of terminals of the second Hall element 20 may extend in different directions on the XY plane of the magnetic sensor 100 described with reference to FIGS. 1 to 4, respectively, with respect to the X axis and the Y axis, respectively. It may be provided in a line symmetrical shape. The first Hall element 10 and the second Hall element may be provided in substantially similar shapes, and are preferably formed in substantially the same shape.

  FIG. 5 shows an example in which the first Hall element 10 and the second Hall element 20 have four terminals. That is, the first Hall element 10 has a terminal 12, a terminal 14, a terminal 16, and a terminal 18, and the second Hall element 20 has a terminal 22, a terminal 24, a terminal 26, and a terminal 28. Here, of the four terminals, two terminals may be aligned in the first direction, and the remaining two terminals may be aligned in a second direction different from the first direction. In this case, the first direction and the second direction may be orthogonal to each other on the XY plane. For example, the first Hall element 10 and the second Hall element 20 may be formed in a cross shape on the XY plane. FIG. 5 shows an example in which the first Hall element 10 and the second Hall element 20 each have four terminals formed in a cross shape.

  The first Hall element 10 and the second Hall element 20 may be formed on the substrate 110 so that the first direction has a predetermined angle with the X axis in the XY plane. For example, the first direction may be substantially parallel to the X axis (in this case, the second direction may be substantially parallel to the Y axis). Alternatively, the angle formed between the first direction and the X axis and the Y axis may be substantially parallel to the direction of approximately 45 degrees (in this case, the angle formed between the second direction and the X axis is approximately 45 degrees). And the angle formed with the Y axis may be substantially parallel to the direction of approximately 135 degrees).

  The first Hall element 10 and the second Hall element 20 may pass a driving current in the first direction and output a measurement voltage from the second direction. Instead, the driving current flows in the second direction. The measurement voltage may be output from the first direction. For example, the first Hall element 10 may pass a driving current between the terminal 12 and the terminal 14 and output a measurement voltage to the outside between the terminal 16 and the terminal 18. Instead, the terminal 16 and the terminal 18 may be used. A measurement current may be output between the terminals 12 and 14 by passing a drive current between the terminals 12 and 14.

  When the drive current flows in the first direction, the first Hall element 10 and the second Hall element 20 function as a drive terminal for injecting the drive current and a current output terminal for outputting the current in the first direction. Two terminals are lined up. Then, two terminals functioning as a positive measurement terminal and a negative measurement terminal are arranged in the second direction, respectively. Further, when a driving current flows in the second direction, the first Hall element 10 and the second Hall element 20 serve as a driving terminal for injecting the driving current and a current output terminal for outputting the current in the second direction. Two functioning terminals are lined up. Then, two terminals functioning as a positive measurement terminal and a negative measurement terminal are arranged in the first direction, respectively.

  The first switch circuit 210 switches between a drive terminal for injecting a drive current, a positive measurement terminal, and a negative measurement terminal between a plurality of terminals of the first Hall element 10. The first switch circuit 210 has a constant current source for supplying a constant current and an external connection terminal for outputting a measurement voltage to the outside. The first switch circuit 210 is connected to a plurality of terminals included in the first Hall element 10 and switches the connection among the plurality of terminals, the constant current source, and the external connection terminal.

  In the example of FIG. 5, the first switch circuit 210 is configured so that each of the terminal 12, the terminal 14, the terminal 16, and the terminal 18 is any one of a drive terminal, a current output terminal, a positive measurement terminal, and a negative measurement terminal. Switch to function as one. For example, when a driving current flows in the first direction, the first switch circuit 210 connects the terminal 12 and the terminal 14 to a constant current source to function as a driving terminal and a current output terminal, respectively. Are respectively connected to the external connection terminals to function as a positive measurement terminal and a negative measurement terminal.

  For example, the first switch circuit 210 may switch between the first combination and the second combination of the connections of the terminals. The first switch circuit 210 includes a plurality of terminals included in the first Hall element 10, a drive terminal for supplying a drive current in the first direction of the first Hall element 10 and a current output terminal, and a second direction different from the first direction. A first combination of a positive measurement terminal and a negative measurement terminal for outputting a measurement voltage of the first Hall element 10 from a drive terminal and a current output terminal for passing a drive current in the second direction of the first Hall element 10; You may switch to either the 2nd combination of the positive measurement terminal and the negative measurement terminal which output the measurement voltage of the 1st Hall element 10 from a 1st direction.

  The second switch circuit 212 switches between a drive terminal for injecting a drive current, a positive measurement terminal, and a negative measurement terminal among a plurality of terminals of the second Hall element 20. The second switch circuit 212 has a constant current source for supplying a constant current and an external connection terminal for outputting a measurement voltage to the outside. The second switch circuit 212 is connected to a plurality of terminals included in the second Hall element 20 and switches the connection among the plurality of terminals, the constant current source, and the external connection terminal.

  In the example of FIG. 5, the second switch circuit 212 is configured so that each of the terminal 22, the terminal 24, the terminal 26, and the terminal 28 is any one of a drive terminal, a current output terminal, a positive measurement terminal, and a negative measurement terminal. Switch to function as one. For example, when the drive current flows in the first direction, the second switch circuit 212 connects the terminal 22 and the terminal 24 to the constant current source to function as the drive terminal and the current output terminal, respectively, and the terminal 26 and the terminal 28. Are respectively connected to the external connection terminals to function as a positive measurement terminal and a negative measurement terminal.

  The second switch circuit 212 switches the drive terminal in the second Hall element 20 to the negative measurement terminal in response to the first switch circuit 210 switching the drive terminal of the first Hall element 10 to the positive measurement terminal. The second switch circuit 212 switches the drive terminal of the second Hall element 20 to the positive measurement terminal in response to the first switch circuit 210 switching the drive terminal of the first Hall element 10 to the negative measurement terminal. May be. The second switch circuit 212 may execute the switching operation of the second Hall element 20 in synchronization with the switching operation of the first switch circuit 210. Further, the first switch circuit 210 and the second switch circuit 212 may perform a switching operation at a predetermined cycle.

  For example, when the first switch circuit 210 switches from a state in which a drive current flows from the terminal 12 to the terminal 14 to a state in which the terminal 12 and the terminal 14 are connected to the external connection terminals, the second switch circuit 212 You may switch from the state in which the drive current is flowing from the terminal 22 to the terminal 24 to the state in which the terminal 22 and the terminal 24 are respectively connected to the external connection terminals. In this case, the second switch circuit 212 uses the terminal 22 and the terminal 24 as external connection terminals so that the first switch circuit 210 has a polarity opposite to that of the terminal 12 and the terminal 14 connected to the external connection terminal. Connecting.

  The first switch circuit 210 selects and switches the drive terminals in a predetermined order from among the plurality of terminals included in the first Hall element 10, and the second switch circuit 212 is driven by the first switch circuit 210. The drive terminals are selected and switched among the plurality of terminals of the second Hall element 20 in the same order as the terminals are selected. For example, when the first switch circuit 210 switches the drive terminals in the order of the terminal 12, the terminal 18, the terminal 14, the terminal 16, the terminal 12,... (That is, counterclockwise in the XY plane), the second switch The circuit 212 may switch the drive terminals in the order of the terminal 22, the terminal 26, the terminal 24, the terminal 28, the terminal 22, and so on (that is, counterclockwise).

  In this case, the second switch circuit 212 may have the same selection order but may have different terminal positions as drive terminals. For example, when the first switch circuit 210 switches the drive terminals in the order of terminal 12, terminal 18, terminal 14, terminal 16, terminal 12,... (Counterclockwise), the second switch circuit 212 drives The terminals may be switched in the order of terminal 26, terminal 24, terminal 28, terminal 22, terminal 26,... (Counterclockwise). Such switching of the first switch circuit 210 and the second switch circuit 212 will be described later.

The first amplification unit 220 amplifies the output signal of the first Hall element 10. The first amplifier 220 may be a differential amplifier circuit. The first amplifying unit 220 may be a transistor differential pair that converts a voltage into a current. The first amplifying unit 220 is connected to, for example, an external connection terminal of the first switch circuit 210 and receives and amplifies an output signal (for example, V _{hall1 +} , V _hall1− ) of the first Hall element 10. The first amplification unit 220 supplies the amplified signal to the first addition unit 230 and the second addition unit 232.

The second amplifying unit 222 amplifies the output signal of the second Hall element 20. The second amplifying unit 222 may be a differential amplifier circuit. The second amplifying unit 222 may be a transistor differential pair that converts a voltage into a current. Second amplifying unit 222 is, for example, is connected to an external connection terminal of the second switch circuit 212, the output signal of the second Hall element 20 _{(e.g., V hall2 +,} V _hall2-) amplifies received a. The second amplification unit 222 supplies the amplified signal to the first addition unit 230 and the second addition unit 232.

The first adder 230 adds the input signals and outputs the result. The first addition unit 230 is connected to, for example, the first amplification unit 220 and the second amplification unit 222, and one of the output signals of the first Hall element 10 (for example, V _{hall1 +} ) and the second Hall element 20 One of the output signals (for example, V _{hall2 +} ) is received, added, and output. The first adding unit 230 may simultaneously add and output the continuous time. That is, the first adder 230 adds the output signals respectively output from the positive measurement terminal of the first Hall element 10 and the positive measurement terminal of the second Hall element 20. The addition may be current addition. The first addition unit 230 supplies the added signal to the amplification unit 240.

The second adder 232 adds the input signals and outputs them. The second adder 232 is connected to the first amplifier 220 and the second amplifier 222, for example, and the other of the output signals of the first Hall element 10 (for example, V _hall− ) and the second Hall element 20. The other output signal (for example, V _hall2- ) is received, added, and output. The second addition unit 232 may simultaneously add and output the continuous time. That is, the second adder 232 adds the output signals respectively output from the negative measurement terminal of the first Hall element 10 and the negative measurement terminal of the second Hall element 20. The addition may be current addition. The second addition unit 232 supplies the added signal to the amplification unit 240.

  The amplification unit 240 receives and amplifies the signal output from the first addition unit 230 and the signal output from the second addition unit 232. The amplifying unit 240 may be a differential amplifier circuit. The amplifier 240 may be a current / voltage conversion circuit. The amplifying unit 240 supplies the amplified signal to the first switching unit 250.

  The first switching unit 250 inverts the sign of the input signal at a predetermined timing. The first switching unit 250 may invert the sign of the signal at a timing synchronized with the switching timing of the first switch circuit 210 and the second switch circuit 212.

  For example, the first switching unit 250 receives an input signal as a differential signal using two signal lines from the amplification unit 240 and outputs the received signal as a differential signal using two signal lines. In this case, the first switching unit 250 connects one of the input signal lines to one of the output signal lines and connects the other of the input signal lines to the other of the output signal lines, or outputs one of the input signal lines. It may be switched between connecting to the other of the signal lines and connecting the other of the input signal lines to one of the output signal lines.

  The first switching unit 250 outputs an output signal to the outside as an output signal of the detection device 200. The first switching unit 250 may output an output signal to the outside via a buffer amplifier or the like. The first switching unit 250 may output the output signal to the outside via an AD conversion unit that converts an analog signal into a digital signal.

  The clock generator 260 generates a clock signal and supplies it to the first switch circuit 210, the second switch circuit 212, and the first switching unit 250. The clock generator 260 supplies the clock signal as a spinning current clock signal. For example, the clock generator 260 may generate a clock signal having a frequency of several kHz to several hundred kHz.

  Note that the detection apparatus 200 may include a feedback loop in order to stabilize the amplification operation. The feedback loop includes a voltage dividing unit 270, a second switching unit 280, and an amplifying unit 290.

The voltage dividing unit 270 divides the output of the first switching unit 250. The voltage dividing unit 270 includes a plurality of resistors and outputs a divided signal corresponding to the resistance value of the resistors. The voltage dividing unit 270 is connected to each of the two signal lines when the output of the first switching unit 250 is a differential output by two signal lines (one is a positive signal and the other is a negative signal). Each partial pressure signal may be generated and output. For example, the voltage dividing unit 270 outputs a negative signal by dividing an output signal by a voltage dividing ratio R ₁ / (R ₁ + R ₂ ) using two resistors having resistance values R ₁ and R ₂ . The positive signal is output by dividing the output signal by the voltage dividing ratio R ₃ / (R ₃ + R ₄ ) by two resistors having resistance values R ₃ and R ₄ . The voltage dividing unit 270 supplies the divided voltage signal to the second switching unit 280.

  The second switching unit 280 selects and switches the supply destination of the divided voltage signal. Second switching unit 280 selects and switches the supply destination of the divided signal in accordance with the clock signal of clock generation unit 260. That is, the output signals of the first Hall element 10 and the second Hall element 20 are modulated by the first switch circuit 210 and the second switch circuit 212 at the timing of the clock signal of the clock generation unit 260, and thus synchronized with the modulation. To switch the feedback signal supply destination.

  For example, the second switching unit 280 transmits the divided signal of the positive (plus side) signal output of the first switching unit 250 during the period in which the modulation signal is the plus side signal. Switch to supply to one signal line. In this case, the second switching unit 280 uses the other signal line different from the signal line that supplies the negative (minus side) signal output voltage of the first switching unit 250 to the positive signal output voltage dividing signal. May be switched to supply. Further, the second switching unit 280 transmits the divided signal of the positive signal output of the first switching unit 250 to the other signal line that transmits the negative signal during a period in which the modulation signal is a negative signal. May be switched to supply. In this case, the second switching unit 280 may perform switching so as to supply the negative signal output divided voltage signal of the first switching unit 250 to one of the signal lines.

  The second switching unit 280 supplies the divided signal as a feedback signal to the first addition unit 230 and the second addition unit 232 via the amplification unit 290, respectively. In this case, the first addition unit 230 and the second addition unit 232 supply the first amplification unit 220, the second amplification unit 222, and a signal obtained by adding the feedback signals to the amplification unit 240, respectively.

  The amplification unit 290 is provided between the second switching unit 280, the first addition unit 230, and the second addition unit 232, and amplifies the feedback signal. The amplifying unit 290 may function as a buffer amplifier. Further, when the feedback signal can be sufficiently supplied, the amplifying unit 290 may be omitted.

If the amplification factors of the first amplification unit 220, the second amplification unit 222, and the amplification unit 290 are G ₁ , G ₂ , and G ₃ , respectively, and the output signals of the first switching unit 250 are V _OUT1 and V _OUT2 , The following equation holds.
(Equation 6)
V _OUT1 = (1 + R ₂ / R ₁ ) {(G ₁ / G ₃ ) V _{hall1 +} + (G ₂ / G ₃ ) V _{hall2 +} }
V _OUT2 = (1 + R ₄ / R ₃ ) {(G ₁ / G ₃ ) V _hall1- + (G ₂ / G ₃ ) V _hall2- }

  The detection apparatus 200 according to the present embodiment described above switches the first switch circuit 210 and the second switch circuit 212 when a magnetic field is applied to the first Hall element 10 and the second Hall element 20 in opposite directions. Control is performed in a predetermined order. A connection state of the first Hall element 10 switched by the first switch circuit 210 will be described with reference to FIGS. Further, the connection state of the second hall element 20 switched by the second switch circuit 212 will be described with reference to FIGS.

FIG. 6 shows a first example of connection of the first Hall element 10 according to the present embodiment. In FIG. 6, the first switch circuit 210 selects the terminal 12 of the first Hall element 10 to which the magnetic field B is applied in the + Z direction as the drive terminal and the terminal 14 as the current output terminal, and connects to the constant current source. An example in which current i flows from terminal 12 to terminal 14 is shown. The constant current source may have a positive common bias V _{C +} for supplying current and a negative common bias V _C− for receiving current. In this case, the first switch circuit 210 adds the terminal 12 to the positive side. The terminal 14 is connected to the common bias V _{C +} on the negative side and the terminal 14 is connected to the common bias V _C− on the negative side. Note that Vc ₊ and Vc ₋ represent the potential as a differential voltage viewed from the common voltage of the Hall element, and in the following description, it is assumed that Vc ₋ = −Vc ₊ .

In addition, the first switch circuit 210 selects the terminal 16 of the first Hall element 10 as a positive measurement terminal and the terminal 18 as a negative measurement terminal, and connects the external connection terminal to the connection. The output signal to be output is supplied to the first amplifying unit 220. In the example of FIG. 6, the first Hall element 10 outputs a positive-side Hall electromotive force signal + V _sig as an output signal V _{hall1 +} from the terminal 16 according to the direction of the magnetic field B and the direction of the current i. Accordingly, the first switch circuit 210 supplies the positive-side Hall electromotive force signal + V _sig to the positive-side input of the differential input of the first amplification unit 220. The first Hall element 10 outputs the negative Hall electromotive force signal −V _sig from the terminal 18 as the output signal V _{hall1 −} . Accordingly, the first switch circuit 210 supplies the negative Hall electromotive force signal −V _sig to the negative input of the differential input of the first amplifier 220.

  FIG. 7 shows a second example of connection of the first Hall element 10 according to the present embodiment. In FIG. 7, the first switch circuit 210 selects the terminal 16 of the first Hall element 10 to which the magnetic field B is applied in the + Z direction as the drive terminal and the terminal 18 as the current output terminal, and connects to the constant current source. An example in which current i flows from terminal 16 to terminal 18 is shown. In addition, the first switch circuit 210 selects the terminal 12 of the first Hall element 10 as a positive measurement terminal and the terminal 14 as a negative measurement terminal, and connects the external connection terminal to the connection. The output signal to be output is supplied to the first amplifying unit 220.

In the example of FIG. 7, the first Hall element 10 outputs a positive Hall electromotive force signal + V _sig as an output signal V _hall1- to the terminal 14 side according to the direction of the magnetic field B and the direction of the current i. Therefore, the first switch circuit 210 supplies the positive Hall electromotive force signal + V _sig to the negative input of the differential input of the first amplifier 220.

FIG. 8 shows a third example of connection of the first Hall element 10 according to the present embodiment. In FIG. 8, the first switch circuit 210 selects the terminal 14 of the first Hall element 10 to which the magnetic field B is applied in the + Z direction as the drive terminal, the terminal 12 as the current output terminal, and the current i from the terminal 14 to the terminal 12. An example is shown. The first switch circuit 210 selects the terminal 16 of the first Hall element 10 as a positive measurement terminal and the terminal 18 as a negative measurement terminal, and outputs an output signal output from the terminal 16 and the terminal 18 to the first amplification unit. 220. In the example of FIG. 8, the first Hall element 10 outputs a positive Hall electromotive force signal + V _sig to the terminal 18 side as an output signal V _hall1- . Therefore, the first switch circuit 210 supplies the positive Hall electromotive force signal + V _sig to the negative input of the differential input of the first amplifier 220.

FIG. 9 shows a fourth example of connection of the first Hall element 10 according to the present embodiment. In FIG. 9, the first switch circuit 210 selects the terminal 18 of the first Hall element 10 to which the magnetic field B is applied in the + Z direction as the drive terminal and the terminal 16 as the current output terminal, and the current i from the terminal 18 to the terminal 16 is selected. An example is shown. The first switch circuit 210 selects the terminal 12 of the first Hall element 10 as a positive measurement terminal and the terminal 14 as a negative measurement terminal, and outputs an output signal output from the terminal 12 and the terminal 14 to the first amplification unit. 220. In the example of FIG. 9, the first Hall element 10 outputs a positive Hall electromotive force signal + V _sig to the terminal 12 side as an output signal V _{hall1 +} . Accordingly, the first switch circuit 210 supplies the positive-side Hall electromotive force signal + V _sig to the positive-side input of the differential input of the first amplification unit 220.

FIG. 10 shows a first example of connection of the second Hall element 20 according to the present embodiment. In FIG. 10, the second switch circuit 212 selects the terminal 22 of the second Hall element 20 to which the magnetic field B is applied in the −Z direction as the drive terminal and the terminal 24 as the current output terminal, and connects to the constant current source. An example in which current i flows from terminal 22 to terminal 24 is shown. In addition, the second switch circuit 212 selects the terminal 26 of the second Hall element 20 as a positive measurement terminal and the terminal 28 as a negative measurement terminal and connects them to the external connection terminals. The output signal to be output is supplied to the second amplifying unit 222. In the example of FIG. 10, the second Hall element 20 outputs the positive-side Hall electromotive force signal + V _sig as the output signal V _{hall 2+} to the terminal 26 according to the direction of the magnetic field B and the direction of the current i. Therefore, the second switch circuit 212 supplies the positive-side Hall electromotive force signal + V _sig to the positive-side input of the differential input of the second amplification unit 222.

FIG. 11 shows a second example of connection of the second Hall element 20 according to the present embodiment. In FIG. 11, the second switch circuit 212 selects the terminal 28 of the second Hall element 20 to which the magnetic field B is applied in the −Z direction as the drive terminal and the terminal 26 as the current output terminal. An example of flowing i is shown. The second switch circuit 212 selects the terminal 24 of the second Hall element 20 as a positive measurement terminal and the terminal 22 as a negative measurement terminal, and outputs an output signal output from the terminal 24 and the terminal 22 to the second amplification unit. 222 is supplied. In the example of FIG. 11, the second Hall element 20 outputs the positive Hall electromotive force signal + V _sig as the output signal V _{hall2 −} to the terminal 22 side. Accordingly, the second switch circuit 212 supplies the positive Hall electromotive force signal + V _sig to the negative input of the differential input of the second amplification unit 222.

FIG. 12 shows a third example of connection of the second Hall element 20 according to the present embodiment. In FIG. 12, the second switch circuit 212 selects the terminal 24 of the second Hall element 20 to which the magnetic field B is applied in the −Z direction as the drive terminal, the terminal 22 as the current output terminal, and the current from the terminal 24 to the terminal 22. An example of flowing i is shown. The second switch circuit 212 selects the terminal 26 of the second Hall element 20 as a positive measurement terminal and the terminal 28 as a negative measurement terminal, and outputs an output signal output from the terminal 26 and the terminal 28 to the second amplification unit. 222 is supplied. In the example of FIG. 12, the second Hall element 20 outputs a positive Hall electromotive force signal + V _sig as an output signal V _hall2− to the terminal 28 side. Accordingly, the second switch circuit 212 supplies the positive Hall electromotive force signal + V _sig to the negative input of the differential input of the second amplification unit 222.

FIG. 13 shows a fourth example of connection of the second Hall element 20 according to the present embodiment. In FIG. 13, the second switch circuit 212 selects the terminal 26 of the second Hall element 20 to which the magnetic field B is applied in the −Z direction as the drive terminal, the terminal 28 as the current output terminal, and the current from the terminal 26 to the terminal 28. An example of flowing i is shown. The second switch circuit 212 selects the terminal 24 of the second Hall element 20 as a positive measurement terminal and the terminal 22 as a negative measurement terminal, and outputs an output signal output from the terminal 24 and the terminal 22 to the second amplification unit. 222 is supplied. In the example of FIG. 13, the second Hall element 20 outputs a positive Hall electromotive force signal + V _sig to the terminal 24 side as an output signal V _{hall 2+} . Therefore, the second switch circuit 212 supplies the positive-side Hall electromotive force signal + V _sig to the positive-side input of the differential input of the second amplification unit 222.

  The detection apparatus 200 according to the present embodiment removes the offset signal and the transient spike signal by combining the connection of the first Hall element 10 and the connection of the second Hall element 20 described above. For example, the first switch circuit 210 selects and switches the drive terminal in a predetermined rotation direction around the first Hall element 10 in the first plane among the plurality of terminals of the first Hall element 10. . That is, the first switch circuit 210 connects the first hall element 10 in accordance with the clock of the clock generator 260 in the order of the connections shown in FIGS. 6, 7, 8, 9, 6,. May be switched. In this case, the first switch circuit 210 selects and switches the drive terminal clockwise with the first hall element 10 as the center, such as the terminal 12, the terminal 16, the terminal 14, the terminal 18, the terminal 12,. Become.

  The second switch circuit 212 selects and switches the drive terminals of the second Hall element 20 in the same order as the order in which the first switch circuit 210 selects the drive terminals. That is, the second switch circuit 212 connects the second Hall element 20 in accordance with the clock of the clock generation unit 260 in the order of connection shown in FIGS. 10, 11, 12, 13, 10,. May be switched. In this case, the second switch circuit 212 selects and switches the drive terminals clockwise around the second hall element 20 with the terminals 22, 28, 24, 26, 22,... Become.

  Signal waveforms when the detection device 200 switches the connection between the first Hall element 10 and the second Hall element 20 in this way will be described with reference to FIG. FIG. 14 shows an example of a signal waveform when the drive terminal of the Hall element according to the present embodiment is selected and switched clockwise. The horizontal axis in FIG. 14 indicates time, and the vertical axis indicates signal intensity.

  Clock generator 260 generates a clock signal for temporally switching clock phases φ1, φ2, φ3, and φ4. The clock signal generated by the clock generator 260 functions as a chopper clock of the spinning current method.

In the waveform of the first Hall element shown in FIG. 14, the first switch circuit 210 switches the connection of the first Hall element 10 from the connection shown in FIG. 6 to the connection shown in FIG. 7 when the clock phase is switched from φ1 to φ2. An example of the signal waveform in the case of In this case, since the terminal 12 is switched from the connection of the positive common bias V _{C +} to the negative Hall electromotive force signal −V _sig , the attenuation curve transiently decreases from V _{C +} to −V _sig . Draw. Further, since the terminal 14 is switched from the connection of the negative common bias V _C− to the positive Hall electromotive force signal + V _sig , a transient curve is drawn which increases from V _C− to + V _sig . . Therefore, the differential signal of the terminal 12 and the terminal 14 with the terminal 12 as the positive side shows an attenuation curve that decreases transiently from 2V _{C +} to −2V _sig , and thereafter maintains a constant value of −2V _sig .

Further, in the waveform of the first Hall element in FIG. 14, the portion where the clock phase is switched from φ2 to φ3 is the signal waveform when the first switch circuit 210 switches from the connection in FIG. 7 to the connection in FIG. An example is shown. In this case, the terminal 16 is _switched from the connection of the positive common bias V _{C +} to the negative Hall electromotive force signal −V _sig , and the terminal 18 is connected to the positive hole from the connection of the negative common bias V _{C−. Switch} to electromotive force signal + V _sig . Therefore, similarly to the case where the clock phase is switched from φ1 to φ2, the differential signal of the terminal 16 and the terminal 18 with the terminal 16 as the positive side has an attenuation curve that transiently decreases from 2V _{C +} to −2V _sig . And then keep a constant value of -2V _sig .

Further, in the waveform of the first Hall element in FIG. 14, the portion where the clock phase is switched from φ3 to φ4 is the signal waveform when the first switch circuit 210 switches from the connection in FIG. 8 to the connection in FIG. An example is shown. In this case, since the terminal 12 switches from the connection of the negative common bias V _C− to the positive Hall electromotive force signal + V _sig , a transition curve that increases transiently from V _C− to + V _sig is obtained. Draw. Further, since the terminal 14 is switched from the connection of the plus-side common bias V _{C +} to the minus-side Hall electromotive force signal −V _sig , a transition curve that decreases from V _{C +} to −V _sig is transiently drawn. . Therefore, the differential signal of the terminal 12 and the terminal 14 with the terminal 12 as the positive side shows an increasing curve that transiently increases from 2V _C− to + 2V _sig , and thereafter maintains a constant value of + 2V _sig .

Further, in the waveform of the first Hall element in FIG. 14, the portion where the clock phase is switched from φ4 to φ1 is the signal waveform when the first switch circuit 210 switches from the connection in FIG. 9 to the connection in FIG. An example is shown. In this case, the terminal 16 is _{switched from} the connection of the negative common bias V _C− to the positive Hall electromotive force signal + V _sig , and the terminal 14 is _switched from the connection of the positive common bias V _{C +} to the negative Hall occurrence. _Switch to power signal -V _sig . Therefore, similarly to the case where the clock phase is switched from φ3 to φ4, the differential signal of the terminal 16 and the terminal 18 with the terminal 16 as the positive side has an increasing curve that transiently increases from 2V _C− to + 2V _sig . And then keep a constant value of + 2V _sig .

Therefore, the waveform of the output signal of the first Hall element 10 includes a modulation signal that switches + 2V _sig and -2V _sig with switching of the clock signal, a spike signal generated on the plus side and the minus side, and an offset signal. Signal. The offset signal is generated as a positive DC component, but is not shown in FIG.

In the waveform of the second Hall element in FIG. 14, the second switch circuit 212 switches the connection of the second Hall element 20 from the connection in FIG. 10 to the connection in FIG. 11 when the clock phase is switched from φ1 to φ2. An example of the signal waveform in the case of In this case, since the terminal 24 is switched from the connection of the negative common bias V _C− to the negative Hall electromotive force signal −V _sig , the increase is transiently increased from V _C− to −V _sig . Draw a curve. Further, since the terminal 22 is switched from the connection of the plus-side common bias V _{C +} to the plus-side Hall electromotive force signal + V _sig , a transition curve that decreases transiently from V _{C +} to + V _sig is drawn. Therefore, the differential signal of the terminal 24 and the terminal 22 with the terminal 24 as the positive side shows an increasing curve that transiently increases from 2V _C− to −2V _sig , and then maintains a constant value of −2V _sig .

Further, in the waveform of the second Hall element in FIG. 14, the second switch circuit 212 connects the connection of the second Hall element 20 from the connection in FIG. 11 to the connection in FIG. An example of the signal waveform when switching is performed. In this case, the terminal 26 is _{switched from} the connection of the negative common bias V _C− to the negative Hall electromotive force signal −V _sig , and the terminal 28 is connected to the positive hole from the connection of the positive common bias V _{C +. Switch} to electromotive force signal + V _sig . Therefore, the differential signal of the terminal 26 and the terminal 28 with the terminal 26 as the positive side shows an increasing curve that transiently increases from 2V _C− to −2V _sig , and then maintains a constant value of −2V _sig .

Further, in the waveform of the second Hall element in FIG. 14, the second switch circuit 212 connects the second Hall element 20 from the connection in FIG. 12 to the connection in FIG. An example of the signal waveform when switching is performed. In this case, the terminal 24 switches from the connection of the positive common bias V _{C +} to the positive Hall electromotive force signal + V _sig, and thus transiently draws an attenuation curve that decreases from V _{C +} to + V _sig . Further, since the terminal 22 switches from the connection of the negative common bias V _C− to the negative Hall electromotive force signal −V _sig , the curve increases transiently from V _C− to −V _sig . Draw. Therefore, the differential signal of the terminal 24 and the terminal 22 with the terminal 24 as the positive side shows an attenuation curve that decreases transiently from 2V _{C +} to + 2V _sig , and then maintains a constant value of + 2V _sig .

Also, in the waveform of the second Hall element in FIG. 14, the second switch circuit 212 connects the second Hall element 20 from the connection in FIG. 13 to the connection in FIG. An example of a signal waveform in the case of switching the above is shown. In this case, the terminal 26 is switched from the connection of the positive common bias V _{C +} to the positive Hall electromotive force signal + V _sig , and the terminal 28 is switched from the connection of the negative common bias V _C− to the negative Hall occurrence. _Switch to power signal -V _sig . Therefore, the differential signals of the terminal 26 and the terminal 28 with the terminal 26 as the positive side show an attenuation curve that decreases transiently from 2V _{C +} to + 2V _sig , and then keeps a constant value of + 2V _sig .

Therefore, the waveform of the output signal of the second Hall element 20 includes a modulation signal in which + 2V _sig and -2V _sig are switched in accordance with switching of the clock signal, a spike signal generated on the plus side and the minus side, and an offset signal. Signal. The offset signal is generated as a positive DC component, but is not shown in FIG.

  Thus, the second switch circuit switches the drive terminal of the second Hall element in the same order as the order of selecting the drive terminal of the first switch circuit, and the first switch circuit switches the drive terminal to the measurement terminal. In response to this, the drive terminal in the second Hall element is switched to the measurement terminal of reverse polarity. As a result, the waveform of the output signal of the second Hall element 20 is compared with the waveform of the output signal of the first Hall element 10 to match the modulation direction of the modulation signal, and the positive and negative directions of the spike signal are reversed. Can be made.

  The first adder 230 and the second adder 232 add the output signals of the first Hall element 10 and the second Hall element 20. As shown in FIG. 14, the signal after the addition is added with the modulation signals having the same modulation direction, so that the amplitude value of the modulation signal is doubled and the inverted spike signal is canceled by the addition. The offset signal exists as a DC component, but is not shown in FIG. Thereby, the detection apparatus 200 can acquire a signal having the Hall electromotive force signal modulated at a frequency half that of the clock signal and the DC component of the offset as an addition signal.

  The first switching unit 250 demodulates the addition signal based on the clock signal from the clock generation unit 260. That is, the first switching unit 250 inverts the polarity of the addition signal with a clock (demodulation clock) having a frequency of the clock signal 1/2 of the clock generation unit 260. Thereby, the 1st switching part 250 can output a Hall electromotive force signal as a DC signal. Note that the offset signal becomes a modulated signal by demodulation and can be removed by a filter or the like. Alternatively, the offset signal may be removed by a filter or the like at the DC component stage before being input to the first switching unit 250.

  As described above, the detection device 200 according to the present embodiment cancels the offset of the Hall element and makes a transient spike signal even when the directions of the magnetic fields input to the two Hall elements are different from each other. Can be reduced. Moreover, the detection apparatus 200 can acquire the Hall electromotive force signal by simple control in which the order of selecting the drive terminals of the Hall elements is the same. Thereby, the detection apparatus 200 can provide a highly accurate magnetic sensor, current sensor, and the like.

  As described above, the detection apparatus 200 according to the present embodiment has been described with respect to the example in which the order of selecting the drive terminals of the two Hall elements is selected clockwise. Alternatively, the detection apparatus 200 may select the order in which the drive terminals of the two Hall elements are selected counterclockwise. That is, the first switch circuit 210 switches the connection of the first Hall element 10 in the order of connections shown in FIGS. 6, 9, 8, 7, 6,..., And the second switch circuit 212 The connection of the second Hall element 20 may be switched in the order of the connections shown in FIGS. 10, 13, 12, 11, 10,.

  As described above, when the detection device 200 switches the order of selecting the drive terminals of the two Hall elements to the same rotation direction, the second switch circuit 212 is different from the selection of the drive terminal of the first switch circuit 210 in phase. The drive terminal of the second Hall element 20 may be selected and switched by shifting. For example, the second switch circuit 212 may select and switch the drive terminal of the second Hall element 20 by shifting the phase by 90 degrees compared to the selection of the drive terminal of the first switch circuit 210.

  More specifically, the first switch circuit 210 switches the connection of the first Hall element 10 in the order of the connections shown in FIGS. 6, 7, 8, 9, 6,. The circuit 212 may switch the connection of the second Hall element 20 in the order of the connections shown in FIGS. 11, 12, 13, 10, 11,. In this case, the second switch circuit 212 connects the positive measurement terminal to the terminal 22 and the negative measurement terminal to the terminal 24 in the connections of FIGS. 11 and 13.

  Further, the second switch circuit 212 may select and switch the drive terminal of the second Hall element 20 by shifting the phase by 180 degrees compared with the selection of the drive terminal of the first switch circuit 210. More specifically, the first switch circuit 210 switches the connection of the first Hall element 10 in the order of the connections shown in FIGS. 6, 7, 8, 9, 6,. The circuit 212 may switch the connection of the second Hall element 20 in the order of the connections shown in FIGS. 12, 13, 10, 11, 12,. In this case, the second switch circuit 212 inverts the connection between the positive measurement terminal and the negative measurement terminal in all the connections shown in FIGS.

  Further, the second switch circuit 212 may select and switch the drive terminal of the second Hall element 20 by shifting the phase by 270 degrees compared to the selection of the drive terminal of the first switch circuit 210. More specifically, the first switch circuit 210 switches the connection of the first Hall element 10 in the order of the connections shown in FIGS. 6, 7, 8, 9, 6,. The circuit 212 may switch the connection of the second Hall element 20 in the order of the connections shown in FIGS. 13, 10, 11, 12, 13,. In this case, the second switch circuit 212 connects the positive measurement terminal to the terminal 28 and the negative measurement terminal to the terminal 26 in the connections of FIGS. 10 and 12.

  Instead of this, the first switch circuit 210 selects and switches the drive terminal to the figure of 8 around the first Hall element 10 in the first plane among the plurality of terminals of the first Hall element 10. Also good. In this case, the second switch circuit 212 switches the drive terminal of the second Hall element 20 in the same order as the order of selection of the drive terminal of the first switch circuit 210 (that is, to the figure 8).

  More specifically, the first switch circuit 210 switches the connection of the first Hall element 10 in the order of connections shown in FIGS. 6, 7, 9, 8, 8,. The circuit 212 may switch the connection of the second Hall element 20 in the order of connections shown in FIGS. 10, 11, 13, 12, 10,. In this case, the first switch circuit 210 reverses the connection between the positive measurement terminal and the negative measurement terminal in the connection shown in FIGS. 8 and 9, and the second switch circuit 212 reverses the connection between the positive measurement terminal and the negative measurement terminal. To.

  FIG. 15 shows an example of a signal waveform when the detection device 200 switches the connection between the first Hall element 10 and the second Hall element 20 in this way. FIG. 15 shows an example of a signal waveform when the drive terminal of the Hall element according to the present embodiment is selected and switched to the figure 8. The horizontal axis in FIG. 15 indicates time, and the vertical axis indicates signal intensity. In FIG. 15, the change of the signal waveform when the clock phase is switched from φ1 to φ2 and when the clock phase is switched from φ3 to φ4 can be explained in the same way as the change explained in FIG. . However, the polarity of the spike signal when switching from φ3 to φ4 is opposite to that in FIG.

In the waveform of the first Hall element in FIG. 15, the clock phase is switched from φ2 to φ3, and the first switch circuit 210 switches the connection of the first Hall element 10 from the connection in FIG. 7 to the connection in FIG. An example is shown. The first switch circuit 210 reversely connects the positive measurement terminal and the negative measurement terminal in FIG. In this case, since the terminal 14 is switched from the connection of the positive Hall electromotive force signal + V _sig to the negative Hall electromotive force signal −V _sig , the attenuation decreases transiently from + V _sig to −V _sig . Draw a curve.

Further, since the terminal 12 switches from the connection of the negative-side Hall electromotive force signal −V _sig to the positive-side Hall electromotive force signal + V _sig , an increasing curve that transiently increases from −V _sig to + V _sig Draw. Therefore, the differential signal of the terminal 14 and the terminal 12 with the terminal 14 as the positive side shows an attenuation curve that decreases transiently from 2V _sig to -2V _sig , and then maintains a constant value of -2V _sig . Since such an attenuation curve is not a variation from the common bias, for example, it does not vary more than the attenuation curve when the clock phase is switched from φ1 to φ2. Therefore, when the clock phase is switched from φ2 to φ3, a spike signal is generated, but the spike signal has a peak value much smaller than the spike signal when the clock phase is switched from φ1 to φ2. Further, this spike signal does not occur when no magnetic field is input, and therefore does not contribute to offset.

  The generation of such a spike signal can be described in the same way for the signal waveform of the first Hall element 10 when the clock phase is switched from φ4 to φ1, and the description thereof is omitted here. Further, since the signal waveform of the second Hall element 20 when the clock phase is switched from φ2 to φ3 and when the clock phase is switched from φ4 to φ1 can be described in the same manner, the description is omitted here.

  Thus, even when the first switch circuit 210 and the second switch circuit 212 switch the selection of the drive terminal to the figure 8, the waveform of the output signal of the second Hall element 20 is the output signal of the first Hall element 10. Compared with the waveform, the modulation direction of the modulation signal can be made to coincide, and the positive and negative directions of the spike signal can be reversed. Therefore, the amplitude value of the modulation signal is doubled by the addition by the first addition unit 230 and the second addition unit 232, and the inverted spike signal can be canceled.

  Further, since the Hall electromotive force signal is modulated and the offset signal becomes a DC component, it can be separated in the frequency domain. Note that the demodulation operation by the first switching unit 250 is substantially the same as the operation described in FIG. As described above, even when the drive terminal selection is switched to the figure 8, the offset of the Hall element can be reduced and the transient spike signal can be reduced. Note that stray capacitances of the first Hall element 10 and the second Hall element 20 are shifted due to manufacturing variations in the process, the intensity of the spike signal of either the first Hall element 10 or the second Hall element 20 is larger, and the spike signal is Cancellation may not be possible. Even in such a case, the polarity of the remaining spike signal after demodulation is reversed with reference to the Hall electromotive force signal every time the phase of the demodulation clock is switched by switching the drive terminal selection to the figure of 8. Therefore, the error can be extremely reduced on average.

  Instead of this, the first switch circuit 210 has a plurality of terminals of the first Hall element 10 having two predetermined combinations of a drive terminal, a current output terminal, a positive measurement terminal, and a negative measurement terminal. You may switch to either. In this case, the second switch circuit 212 drives the second Hall element 20 in the same order as the selection order of the drive terminals of the first switch circuit 210 (that is, in one of two predetermined combinations). Switch the terminal.

  More specifically, the first switch circuit 210 switches the connection of the first Hall element 10 in the order of connections shown in FIGS. 6, 7, 6, 7, 6,... The circuit 212 may switch the connection of the second Hall element 20 in the order of the connections shown in FIGS. 12, 13, 12, 13, 12,. That is, the first switch circuit 210 and the second switch circuit 212 switch the connection between the first Hall element 10 and the second Hall element 20 so that the clock phases are switched to φ1, φ2, φ1, φ2,. It's okay. In this case, the second switch circuit 212 reverses the connection between the positive measurement terminal and the negative measurement terminal in the connection shown in FIGS.

  FIG. 16 shows an example of a signal waveform when the detection apparatus 200 switches the connection between the first Hall element 10 and the second Hall element 20 in this way. FIG. 16 shows an example of a signal waveform when the drive terminal of the Hall element according to the present embodiment is switched between two predetermined connections. The horizontal axis in FIG. 16 indicates time, and the vertical axis indicates signal intensity. In FIG. 16, the change in the signal waveform when the clock phase is switched can be described in the same manner as the change described in FIG.

  From FIG. 16, even when the first switch circuit 210 and the second switch circuit 212 switch the drive terminal selection between two predetermined connections, the waveform of the output signal of the second Hall element 20 is the first Compared to the waveform of the output signal of the Hall element 10, the modulation direction of the modulation signal can be matched, and the positive and negative directions generated by the spike signal can be reversed. Therefore, the amplitude value of the modulation signal is doubled by the addition by the first addition unit 230 and the second addition unit 232, and the inverted spike signal can be canceled. Further, since the Hall electromotive force signal is modulated and the offset signal becomes a DC component, it can be separated in the frequency domain. Note that stray capacitances of the first Hall element 10 and the second Hall element 20 are shifted due to manufacturing variations in the process, the intensity of the spike signal of either the first Hall element 10 or the second Hall element 20 is larger, and the spike signal is Cancellation may not be possible. Even in such a case, by switching the drive terminal between two predetermined connections, the spike signal remaining after demodulation is converted to the Hall electromotive force signal every time the phase of the demodulation clock is switched. Since the polarity is generated while reversing the polarity as a reference, the error can be extremely reduced on average.

  The detection apparatus 200 according to the present embodiment has been described with respect to the example in which the offset of the Hall element is canceled and the transient spike signal is reduced by using two Hall elements. Instead of this, the detection device 200 may use three or more Hall elements.

  For example, when a Hall element is formed by a process such as doping an impurity into the substrate 110, the impurity concentration may not be constant inside the Hall element, and a concentration gradient in which the concentration of the impurity concentration is inclined in a certain direction may occur. In such a case, even if the same magnetic field is input, the signal strength of the offset may vary depending on the position of the drive terminal of the Hall element.

  Therefore, the detection apparatus 200 uses three or more Hall elements to vary the position of the drive terminal of each Hall element, average the fluctuation of the offset due to the concentration gradient, and reduce the signal component of the offset. it can. An example of such a detection apparatus 200 will be described with reference to FIGS. 17 and 18.

  FIG. 17 shows a configuration example of the upper surface of the magnetic sensor 100 when four Hall elements according to this embodiment are used. FIG. 17 is a modified example of the first magnetic sensor 100 shown in FIG. 2, and the same reference numerals are given to substantially the same operations as those of the magnetic sensor 100 according to the present embodiment shown in FIG. Is omitted. The magnetic sensor 100 of this modification further includes a third Hall element 30 and a fourth Hall element 40. FIG. 17 illustrates an example in which a concentration gradient is generated in the direction of the arrow 112.

  The third Hall element 30 has a plurality of terminals to which a magnetic field to be detected is applied in the same direction as the first Hall element 10 and extends in the same direction as the plurality of terminals of the first Hall element 10. The third Hall element 30 includes a terminal 32, a terminal 34, a terminal 36, and a terminal 38, and is formed in substantially the same shape as the first Hall element 10. As an example, the third Hall element 30 is formed side by side in the direction parallel to the first Hall element 10 and the X axis in the XY plane. The third Hall element 30 receives a magnetic field substantially the same as that of the first Hall element 10 by the magnetic converging plate 120. For example, when a magnetic field in the + Y direction is input to the magnetic sensor 100, the magnetic field in the + Z direction is input to the third Hall element 30.

  The fourth Hall element 40 has a plurality of terminals to which a magnetic field to be detected is applied in the same direction as the second Hall element 20 and extends in the same direction as the plurality of terminals of the second Hall element 20. The fourth Hall element 40 includes a terminal 42, a terminal 44, a terminal 46, and a terminal 48, and is formed in substantially the same shape as the second Hall element 20. As an example, the fourth Hall element 40 is formed side by side in the direction parallel to the second Hall element 20 and the X axis in the XY plane. The fourth Hall element 40 receives a magnetic field substantially the same as that of the second Hall element 20 through the magnetic flux concentrating plate 122. For example, when a magnetic field in the + Y direction is input to the magnetic sensor 100, the fourth Hall element 40 receives a magnetic field in the -Z direction.

  The first Hall element 10, the second Hall element 20, the third Hall element 30, and the fourth Hall element 40 may have a cross shape having four terminals extending in four different directions from the center. Further, the extending directions of the four terminals may be four directions in which angles formed with the X axis and the Y axis are approximately 45 degrees and approximately 135 degrees, respectively.

  In the detection apparatus 200 according to the present embodiment, the first Hall element 10, the second Hall element 20, the third Hall element 30, and the fourth Hall element are terminals that face different directions with respect to the magnetic sensor 100. Switch to 40 drive terminals. For example, the detection apparatus 200 includes the terminal 12 of the first Hall element 10, the terminal 24 of the second Hall element 20, the terminal 32 of the third Hall element 30, and the terminal of the fourth Hall element 40 in the clock phase φ1 of the clock signal. 44 may be a drive terminal. And the detection apparatus 200 may switch the drive terminal of each Hall element clockwise or counterclockwise according to the clock signal. Instead of this, the detection device 200 may switch the drive terminal of each Hall element to the figure 8 in accordance with the clock signal.

  FIG. 18 shows a configuration example of the detection apparatus 200 when four Hall elements according to this embodiment are used. FIG. 18 is a modification of the detection apparatus 200 shown in FIG. 5, and the same reference numerals are given to the substantially same operations as those of the detection apparatus 200 according to the present embodiment shown in FIG. . The detection apparatus 200 according to the present modification further includes a third switch circuit 214, a fourth switch circuit 216, a third amplifying unit 224, and a fourth amplifying unit 226.

The third switch circuit 214 switches between a drive terminal for injecting a drive current, a positive measurement terminal, and a negative measurement terminal between a plurality of terminals of the third Hall element 30. The third amplifying unit 224 amplifies the output signal of the third hall element 30. The third amplifying unit 224 may be a differential amplifier circuit. The third amplifying unit 224 may be a transistor differential pair that converts a voltage into a current. The third amplifying unit 224 is connected to, for example, an external connection terminal of the third switch circuit 214, receives and amplifies the signal output from the third Hall element 30 (for example, V _{hall3 +} , V _hall3− ), and amplifies the amplified signal. This is supplied to the first addition unit 230 and the second addition unit 232.

The fourth switch circuit 216 switches between a drive terminal for injecting a drive current, a positive measurement terminal, and a negative measurement terminal between a plurality of terminals of the fourth Hall element 40. The fourth amplification unit 226 amplifies the output signal of the fourth Hall element 40. The fourth amplifier 226 may be a differential amplifier circuit. The fourth amplifying unit 226 may be a transistor differential pair that converts a voltage into a current. For example, the fourth amplifying unit 226 is connected to the external connection terminal of the fourth switch circuit 216, receives and amplifies the output signal (for example, V _{hall4 +} , V _hall4− ) of the fourth Hall element 40, and amplifies the amplified signal. This is supplied to the first addition unit 230 and the second addition unit 232.

  First addition unit 230 and second addition unit 232 add the signals received from first amplification unit 220, second amplification unit 222, third amplification unit 224, fourth amplification unit 226, and amplification unit 290, respectively. Each is supplied to the amplifying unit 240. The addition may be current addition.

  In the detection device 200 described above, as described with reference to FIG. 17, the first switch circuit 210, the second switch circuit 212, the third switch circuit 214, and the fourth switch circuit 216 have terminals that face different directions from each other. Switching is performed so that the drive terminals of the Hall element 10, the second Hall element 20, the third Hall element 30, and the fourth Hall element 40 are used. Thereby, the detection apparatus 200 can average the fluctuation of the offset due to the concentration gradient and reduce the signal component of the offset. Further, the detection device 200 can reduce the transient spike signal while reducing the offset of the Hall element.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

10 First Hall element, 12, 14, 16, 18 terminals, 20 Second Hall element, 22, 24, 26, 28 terminals, 30 Third Hall element, 32, 34, 36, 38 terminals, 40 Fourth Hall element 42, 44, 46, 48 terminals, 100 magnetic sensor, 110 substrate, 112 arrow, 120 magnetic convergence plate, 122 magnetic convergence plate, 130 current conductor, 200 detection device, 210 first switch circuit, 212 second switch circuit, 214 3rd switch circuit, 216 4th switch circuit, 220 1st amplification part, 222 2nd amplification part, 224 3rd amplification part, 226 4th amplification part, 230 1st addition part, 232 2nd addition part, 240 amplification Section, 250 first switching section, 260 clock generation section, 270 voltage dividing section, 280 second switching section, 290 amplification section

Claims (14)

A detection device for detecting a magnetic field,
A first Hall element and a second Hall element magnetic field to be detected is applied in the opposite direction to each other,
A first switch circuit for switching a drive terminal for injecting a drive current, a positive measurement terminal, and a negative measurement terminal between a plurality of terminals of the first Hall element;
A second switch circuit for switching a drive terminal for injecting a drive current, a positive measurement terminal, and a negative measurement terminal between a plurality of terminals of the second Hall element;
Output signals respectively output from the positive measurement terminal of the first Hall element and the positive measurement terminal of the second Hall element are added, and the negative measurement terminal and the second Hall of the first Hall element are added. An adder for adding output signals respectively output from the negative measurement terminals of the element;
A clock generator for generating a clock signal;
With
The first switch circuit and the second switch circuit modulate a signal from the first Hall element and the second Hall element based on the clock signal by a spinning current method,
The second switch circuit includes:
In response to the first switch circuit injecting the drive current into the positive measurement terminal of the first Hall element and switching the positive measurement terminal to the drive terminal at the timing when the phase of the clock signal is switched , Injecting the drive current into the negative measurement terminal in the second Hall element to switch the negative measurement terminal to the drive terminal; and
In response to the first switch circuit injecting the drive current into the negative measurement terminal of the first Hall element and switching the negative measurement terminal to the drive terminal at the timing when the phase of the clock signal is switched, Injecting the drive current into the positive measurement terminal of the second Hall element to switch the positive measurement terminal to the drive terminal;
Do one of the
The adding unit is configured so that the polarity of the positive measurement terminal of the second Hall element and the polarity of the negative measurement terminal are negative with respect to the polarity connected to the positive measurement terminal and the negative measurement terminal of the first Hall element. Detection device connected to the measurement terminal . The second switch circuit includes:
The negative measurement in the second Hall element in response to the first switch circuit switching between the positive measurement terminal and the drive terminal in the first Hall element at the timing when the phase of the clock signal switches. Switching between the terminal and the drive terminal; and
The positive measurement in the second Hall element in response to the first switch circuit switching between the negative measurement terminal and the drive terminal in the first Hall element at the timing when the phase of the clock signal is switched. Switching between the terminal and the drive terminal;
The detection device according to claim 1 which performs one of the following. The first switch circuit selects and switches drive terminals in a predetermined order among the plurality of terminals of the first Hall element,
The second switch circuit is in the same order in which the first switch circuit selects a drive terminal, to claim 1 or 2 switches select the driving terminals of the plurality of terminals, wherein the second Hall element has The detection device described. The detection device according to claim 3 , wherein the second switch circuit selects and switches the drive terminal of the second Hall element with a phase shifted from the selection of the drive terminal of the first switch circuit. The plurality of terminals included in the first Hall element extend in different directions from the first Hall element on the first plane,
5. The detection according to claim 1, wherein the plurality of terminals included in the second Hall element extend in the same direction as the plurality of terminals included in the first Hall element on the first plane. apparatus. The first switch circuit includes the plurality of terminals included in the first Hall element.
The drive terminal and the current output terminal for passing a drive current in the first direction of the first Hall element, and the positive measurement terminal for outputting the measurement voltage of the first Hall element from a second direction different from the first direction And a combination of the negative measurement terminals,
The drive terminal and the current output terminal for passing a drive current in the second direction of the first Hall element, the positive measurement terminal and the negative measurement for outputting the measurement voltage of the first Hall element from the first direction In combination with terminals,
The detection device according to claim 5, wherein the detection device is switched to any one of the above.   The first switch circuit selects the drive terminal in a predetermined rotation direction centered on the first Hall element in the first plane among the plurality of terminals of the first Hall element. The detection device according to claim 5 or 6 to be switched.   7. The first switch circuit selects and switches the drive terminal to a figure of 8 around the first Hall element in the first plane among the plurality of terminals of the first Hall element. The detection device according to 1.   The first switch circuit includes a plurality of terminals included in the first Hall element, the combination of two predetermined combinations of the drive terminal, the current output terminal, the positive measurement terminal, and the negative measurement terminal. The detection device according to claim 6, wherein the detection device is switched to any one. A third Hall element having a plurality of terminals each having a magnetic field to be detected applied in the same direction as the first Hall element and extending in the same direction as the plurality of terminals of the first Hall element;
A fourth Hall element having a plurality of terminals each having a magnetic field to be detected applied in the same direction as the second Hall element and extending in the same direction as the plurality of terminals of the second Hall element;
A third switch circuit for switching a drive terminal for injecting a drive current, a positive measurement terminal, and a negative measurement terminal between the plurality of terminals of the third Hall element;
A fourth switch circuit for switching a drive terminal for injecting a drive current, a positive measurement terminal, and a negative measurement terminal between the plurality of terminals of the fourth Hall element;
With
In the first switch circuit, the second switch circuit, the third switch circuit, and the fourth switch circuit, terminals that face different directions are connected to the first Hall element, the second Hall element, and the third Hall element, respectively. And the detection device according to claim 1, wherein the detection device is switched so as to be a drive terminal of the fourth Hall element.   The detection apparatus according to any one of claims 1 to 10, further comprising a magnetic converging plate that converges by changing a direction of a magnetic field to be detected.   The detection device according to any one of claims 1 to 11, further comprising an amplifying unit that amplifies output signals from the first Hall element and the second Hall element, respectively. The detection device according to any one of claims 1 to 12, wherein the detection device is disposed on a current conductor,
The detection device in which the current conductor extends parallel to a plane including the first Hall element and the second Hall element above or below a point between the first Hall element and the second Hall element. The detection device according to any one of claims 1 to 12,
A current conductor extending in a predetermined direction;
With
The current conductor extends in parallel with a plane including the first Hall element and the second Hall element above or below a point between the first Hall element and the second Hall element.

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