JP4293922B2 - Magnetic orientation detector - Google Patents

Description

  The present invention relates to a geomagnetic detection technique, and more particularly to a magnetic orientation detection device using a Hall element.

  2. Description of the Related Art Conventionally, an azimuth detecting device that measures geomagnetism and detects an azimuth is frequently used as an azimuth information complementing unit in an in-vehicle navigation system or the like. Since these azimuth detection devices are excellent in sensitivity, it is common to use a fluxgate type magnetic sensor using a toroidal core, and a geomagnetic sensor as a relatively small azimuth detection device has been proposed ( For example, see Patent Document 1).

  In the geomagnetic sensor of Patent Document 1, a magnetism detection unit is formed by integrating a plurality of substrate layers, and an excitation coil that winds an X and Y detection coil and an amorphous toroidal core is formed according to the substrate pattern of the substrate layer. It is composed. The signal processing circuit includes a first analog switch, a second analog switch, a first integration circuit for integrating the output of the first analog switch, and a second integration for integrating the output of the second analog switch. It comprises an integration circuit, a differential amplifier for differentiating the outputs of the first integration circuit and the second integration circuit, an A / D converter for converting the output of the differential amplifier into a digital signal, and the like. According to this geomagnetic sensor, since it is formed by a substrate in which an exciting coil wound around a toroidal core and two detection coils X and Y are laminated, it is relatively easy to downsize, and it can be applied to a portable information device or the like. Application is also possible.

  As another proposal, a small electronic compass has been proposed as an azimuth detecting device using a magneto-impedance effect element (hereinafter abbreviated as MI element) (see, for example, Patent Document 2). The electronic compass of Patent Document 2 includes a first MI element that is a means for detecting the geomagnetic X-axis direction component, and a second MI element that is a means for detecting the geomagnetic Y-axis direction component, The first and second MI elements are arranged in the same plane so that the current paths of the alternating current applied thereto are orthogonal to each other. Since the MI element used in this electronic compass is highly sensitive to the lines of magnetic force, it is possible to develop an orientation detection device suitable for detecting weak geomagnetism.

JP 2002-243818 (Claims, Fig. 1) Japanese Patent Laid-Open No. 11-63997 (Claims, Fig. 1)

  However, since the geomagnetic sensor of Patent Document 1 employs a circular toroidal core, there is a limit to downsizing. In addition, although the toroidal core is made of an amorphous material, the amorphous material has a coercive force so that it is easily magnetized, and there is a drawback that an error is likely to occur in a measured value due to hysteresis. In addition, an analog switch and a differential amplifier are required for the detection circuit, and the circuit configuration is complicated, which increases the cost. Furthermore, in order to magnetically saturate the toroidal core, a drive current of several tens of mA is required, and there is a problem in incorporating it into a portable electronic device from the viewpoint of power consumption.

  Further, since the MI element employed in the electronic compass disclosed in Patent Document 2 has a coil shape in which a conductive wire is wound around an amorphous material, there is still a limit to downsizing. Further, a high frequency or pulse current is required as a drive signal for driving the MI element, and the drive circuit is complicated, resulting in an increase in cost. In order to detect geomagnetism with high accuracy, it is preferable to perform triaxial geomagnetism detection, but there is a problem that it is difficult to mount an MI element that detects geomagnetism in the Z-axis direction, which is the vertical direction.

  An object of the present invention is to solve the above-mentioned problems and provide a magnetic orientation detection device that is small in size, high in detection accuracy, excellent in reliability, and low in cost as a built-in portable information device.

  In order to solve the above-mentioned problems, the magnetic azimuth detecting device of the present invention employs the following configuration.

The magnetic orientation detection device of the present invention drives a plurality of magnetic sensor elements and the plurality of magnetic sensor elements on an insulating substrate having a plurality of terminal electrodes for electrical connection with the outside. The two magnetic sensor elements for detecting a geomagnetic component in a horizontal direction with respect to the insulating substrate are arranged with a semiconductor that inputs a detection signal from the sensor element and outputs magnetic information corresponding to the strength of the magnetism. The magnetic sensor module is mounted on a sensor board to form a magnetic sensor module, and the magnetic sensor module is side-mounted on the insulating board by solder mounting, and the other magnetism for detecting a geomagnetic component in a direction perpendicular to the insulating board. sensor element, wherein the bare mounted on the insulating substrate, to characterized in that integrated sealed and the and the magnetic sensor module and the other of the magnetic sensor element semiconductor with a sealing member .

  According to the magnetic azimuth detecting device of the present invention, a plurality of magnetic sensor elements and a semiconductor that drives the magnetic sensor elements and obtains magnetic information can be integrated, so that an extremely small magnetic azimuth detecting device can be realized.

In addition, a plurality of magnetic sensor elements and a plurality of magnetic sensor elements are driven on an insulating substrate having a plurality of terminal electrodes for electrical connection with the outside, and detection signals from the plurality of magnetic sensor elements are output. A semiconductor that inputs and outputs magnetic information corresponding to the strength of the magnetism, and an arithmetic means that inputs the magnetic information from the semiconductor and calculates the orientation are arranged, and the geomagnetism in the horizontal direction with respect to the insulating substrate The two magnetic sensor elements for detecting components are mounted on a sensor substrate to form a magnetic sensor module, and the magnetic sensor module is mounted on the side surface of the insulating substrate by solder mounting and is perpendicular to the insulating substrate. another of the magnetic sensor element for detecting the direction of geomagnetism component, the are bare mounted on the insulating substrate, wherein the magnetic sensor module and the other of the magnetic sensor element and the semiconductor and the calculating means The is characterized in that integrally sealed by a sealing member.

  As a result, the calculation means for inputting the magnetic information and calculating the azimuth is integrated and integrated, so the digitized azimuth information can be obtained directly, and the processing load of the portable information device incorporating the magnetic azimuth detection device is reduced. It is possible to realize an information device that is reduced and has excellent processing capability.

One of the magnetic sensor modules detects a geomagnetic component in the X-axis direction of the plane of the insulating substrate, and the other magnetic sensor module has an angle of 90 degrees with respect to the X-axis direction. The geomagnetic component in the axial direction is detected, and the other magnetic sensor elements are arranged to detect the geomagnetic component in the Z-axis direction that is perpendicular to the plane in the X-axis direction and the Y-axis direction. It is characterized by.

  As a result, geomagnetism can be detected in the X-axis direction, Y-axis direction, and Z-axis direction, and in the three-axis direction. I can do it.

  In addition, the magnetic sensor module is mounted on the insulating substrate by lead-free solder.

  As a result, since the solder mounting is performed using lead-free solder, it is possible to provide a magnetic orientation detection device that is free from environmental pollution due to lead.

  Further, the plurality of magnetic sensor elements are hall elements.

  Thereby, it is possible to provide a magnetic azimuth detecting device that is small in size, simple in driving circuit and detecting circuit, and low in cost.

  As described above, according to the present invention, a plurality of magnetic sensor elements arranged in the X-axis direction, the Y-axis direction, and the Z-axis direction and a semiconductor that drives the plurality of magnetic sensor elements and obtains magnetic information are integrated. Therefore, a small and high-performance magnetic direction detection device can be realized.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a configuration diagram of a magnetic azimuth detecting device according to a first embodiment of the present invention. FIG. 1 (a) is a top view of the magnetic azimuth detecting device, and FIG. 1 (b) is a perspective view of the magnetic azimuth detecting device. FIG. 2 is a configuration diagram of a magnetic sensor module mounted on the magnetic orientation detection device of the present invention, FIG. 2 (a) is a front perspective view of the magnetic sensor module, and FIG. 2 (b) is a top view of the magnetic sensor module. It is. FIG. 3 is a side view of a magnetic sensor module mounted on the magnetic orientation detection device of the present invention. FIG. 4 is a circuit block diagram of the magnetic orientation detection apparatus according to the first embodiment of the present invention.

  FIG. 5 shows the geomagnetic detection characteristics in the X-axis direction and the Y-axis direction of the magnetic azimuth detecting device of the present invention, and FIG. 5 (a) is an explanatory diagram of the measurement of the geomagnetic detection characteristics of the magnetic azimuth detecting device. ) Is a geomagnetic detection characteristic graph in the X-axis direction and the Y-axis direction of the magnetic bearing detection device. FIG. 6 shows the geomagnetic detection characteristics in the X-axis direction and the Z-axis direction of the magnetic azimuth detecting device of the present invention, and FIG. 6 (a) is an explanatory diagram of the measurement of the geomagnetic detection characteristics of the magnetic azimuth detecting device. ) Is a geomagnetic detection characteristic graph in the X-axis direction and the Z-axis direction of the magnetic bearing detection device. FIG. 7 is a top view of the magnetic orientation detection apparatus according to the second embodiment of the present invention. FIG. 8 is a circuit block diagram of a magnetic bearing detection apparatus according to Embodiment 2 of the present invention.

  The configuration of the magnetic azimuth detecting device of the present invention as Embodiment 1 will be described with reference to FIG. 1 (a) and 1 (b), reference numeral 1 denotes a magnetic azimuth detecting device of the present invention. Reference numeral 2 denotes a circuit board as a substantially rectangular insulating substrate, preferably made of a heat-resistant glass epoxy substrate, a ceramic substrate or the like and having a thickness of about 0.3 mm. Reference numerals 2a to 2h denote through-hole electrodes as terminal electrodes disposed around the circuit board 2. The through-hole electrodes 2a to 2h are formed up to a part of the back surface of the circuit board 2 (not shown), and are electrically connected to the outside. It functions as a terminal electrode connected to.

  That is, when the magnetic orientation detection device 1 is incorporated into a portable information device or the like, the through-hole electrodes 2a to 2h can be fixed to a substrate of the portable information device or the like by surface mounting with solder or the like. Although the number of the through-hole electrodes 2a to 2h is eight in this embodiment, the number is not limited to this number, and may be increased or decreased according to the specification. Moreover, the terminal electrode of the magnetic direction detection apparatus 1 is not limited to the form of the through-hole electrodes 2a to 2h, and may be any form of terminal electrode.

  Reference numerals 3 and 4 denote magnetic sensor modules incorporating Hall elements as magnetic sensor elements, which are mounted on the circuit board 2, respectively. Here, the magnetic sensor module 3 is side-mounted by solder (not shown) or the like so as to detect a geomagnetic component in the X-axis direction (arrow X) of the plane of the circuit board 2. Side mounting is performed by solder (not shown) or the like so as to detect the geomagnetic component in the Y-axis direction (arrow Y) having an angle of 90 degrees with respect to the mounting direction of the magnetic sensor module 3 in the plane of 2. The detailed configuration and mounting form of the magnetic sensor modules 3 and 4 will be described later.

  Reference numeral 5 denotes a Hall element as a magnetic sensor element that detects a geomagnetic component in the Z-axis direction (arrow Z) that is perpendicular to the plane of the circuit board 2 and is bare-mounted on the circuit board 2 by wire bonding. That is, the Hall element 5 is preferably fixed to the circuit board 2 with a non-conductive adhesive paste (not shown), and electrically connected to the plurality of connection electrodes 7a on the circuit board 2 by a plurality of wires 6a made of fine metal wires. Connected and implemented. The bare mounting of the Hall element 5 is not limited to wire bonding mounting, but may be flip chip mounting using, for example, solder balls.

  Reference numeral 8 denotes a drive detection IC as a semiconductor, which is fixed to the circuit board 2 with a conductive paste (not shown) or the like and electrically connected to the plurality of connection electrodes 7b on the circuit board 2 by a plurality of wires 6b made of fine metal wires. Connected to and implemented. The mounting of the drive detection IC 8 is not limited to wire bonding mounting, but may be flip chip mounting using solder balls or the like, for example. The details of the internal structure of the drive detection IC 8 will be described later. Reference numeral 9 denotes a sealing member made of an insulating resin or the like, which seals and magnetically protects the magnetic sensor modules 3 and 4, the Hall element 5, and the plurality of wires 6 a and 6 b.

  In the top view of FIG. 1A, a circuit pattern of a copper foil or the like is formed on the circuit board 2 but is omitted. Further, as described above, in FIG. 1A, the magnetic sensor modules 3, 4 and the Hall element 5, the drive detection IC 8 and the like are actually sealed by the sealing member 9, so that it can be seen. Although not possible, for convenience of explanation, the sealing member 9 is shown here. As described above, the magnetic sensor modules 3 and 4 that detect the geomagnetic components in the X-axis direction and the Y-axis direction, the Hall element 5 that detects the geomagnetic component in the Z-axis direction, and the drive detection IC 8 are mounted on the circuit board 2. They are mounted together and sealed and integrated by a sealing member 9. The sealing member 9 is preferably made of an insulating resin, but is not limited thereto, and may be covered with a non-magnetic case or the like.

  Next, the detailed structure and mounting form of the magnetic sensor module 3 will be described with reference to FIG. Since the magnetic sensor module 4 is the same as the magnetic sensor module 3, the description thereof is omitted. In FIG. 2A, reference numeral 10 denotes a Hall element as a substantially cubic magnetic sensor element, which is directly fixed to the surface substrate of the sensor substrate 3a of the magnetic sensor module 3 by an adhesive paste 3b. The electrodes 3c to 3f are a plurality of electrodes formed on the surface of the sensor substrate 3a, and the tips of the electrodes 3c to 3f are close to the Hall element 10 as shown in the figure.

  3g is a plurality of wires made of fine metal wires, and electrically connects the tips of the electrodes 3c to 3f and the four terminal electrodes (not shown) of the Hall element 10. In practice, the Hall element 10, the wire 3g, and the like are sealed and mechanically protected by a sealing member, but here, for the sake of convenience of explanation, they are shown as a transparent view through the sealing member. As an example, the external size of the magnetic sensor module 3 is about 2.8 mm in length and about 0.6 mm in height.

  Next, a mounting form of the magnetic sensor module 3 will be described with reference to FIG. In FIG. 2 (b), the circuit board 2 is represented by a simple rectangle and small for convenience of explanation, but actually has a structure and size as shown in FIG. Yes. 11 a to 11 d are conductive patterns formed on the circuit board 2, and function as mounting electrodes for mounting the magnetic sensor module 3. 12a to 12d are solders for fixing the magnetic sensor module 3 to the circuit board 2 and are preferably lead-free solders. Moreover, it is preferable that the solders 12a to 12d are low-residue solders with little impurity residue.

  The conductive patterns 11 a to 11 d are preferably substantially circular with no corners so that the flux of the solders 12 a to 12 d does not adhere to the magnetic sensor module 3. Reference numerals 13a to 13c denote resist patterns, which are formed as a guide for mounting positions of the magnetic sensor module 3, but in order to release the flux of the solders 12a to 12d, the conductive patterns 11a to 11d are not completely covered. preferable. Reference numeral 3h denotes a sealing member for sealing the Hall element 10 and the wire 3g of the magnetic sensor module 3, but the sealing member 3h is shown here transparently for convenience of explanation.

  Next, FIG. 3 is a mounting side view of the magnetic sensor module 3 as seen from the arrow A in FIG. As shown in the figure, the magnetic sensor module 3 is mounted on the side surface of the circuit board 2, so that the Hall element 10 mounted on the sensor board 3a is arranged perpendicular to the circuit board 2 as shown in the figure. It has maximum sensitivity with respect to the direction of the magnetic field indicated by B. That is, the magnetic sensing direction of the magnetic sensor module 3 is a horizontal direction with respect to the circuit board 2. The sealing member 3h that covers and seals the Hall element 10 and the like is shown in a transparent manner for convenience of explanation. Therefore, the component height of the magnetic sensor module 3 is about 0.6 mm from the conductive patterns 11a to 11d of the circuit board 3 as described above.

  As described above, the magnetic sensor modules 3 and 4 for detecting the geomagnetic components in the X-axis direction and the Y-axis direction are mounted on the side surface of the circuit board 2 with solder. On the other hand, the geomagnetic component in the horizontal direction can be detected efficiently. Further, since the magnetic sensor modules 3 and 4 are extremely low profile with a component height of about 0.6 mm, the height of the magnetic direction detecting device 1 on which the magnetic sensor modules 3 and 4 are mounted is also kept extremely low. Is possible. In addition, since the Hall element 5 is bare-mounted on the circuit board 2, it can detect a geomagnetic component in the Z-axis direction that is perpendicular to the plane of the circuit board 2, and because it is bare-mounted by wire bonding It is possible to provide a small and low-profile magnetic orientation detection device with a small mounting area.

  Next, an outline of a circuit configuration of the magnetic orientation detection apparatus according to the first embodiment of the present invention will be described with reference to FIG. In FIG. 4, a block surrounded by a large broken line is the magnetic azimuth detecting device 1, and a block surrounded by the broken line is a drive detection IC 8. The drive detection IC 8 has three differential amplifiers 8a to 8c therein. In the differential amplifiers 8a to 8c, feedback resistors 8d to 8f are connected between the negative input terminal and the output terminal, respectively. The negative input terminals and the positive input terminals of the differential amplifiers 8a to 8c are connected to the outside of the drive detection IC 8. Reference numeral 8g denotes a DC power source for driving the Hall element, the plus terminal of which is output to the outside of the drive detection IC 8 as the drive voltage P1, and the minus terminal is connected to the minus power source Vss.

  The electrode 3c of the magnetic sensor module 3 that detects geomagnetism in the X-axis direction receives the drive voltage P1 from the drive detection IC 8, and the electrode 3f is connected to the negative power source Vss. The electrodes 3d and 3e of the magnetic sensor module 3 output detection signals P3a and P3b that change according to the detected magnetic field, and input to the negative input terminal and the positive input terminal of the differential amplifier 8a of the drive detection IC 8, respectively. Is done. The electrode 4c of the magnetic sensor module 4 that detects the geomagnetism in the Y-axis direction receives the drive voltage P1 from the drive detection IC 8, and the electrode 4f is connected to the negative power source Vss. The electrodes 4d and 4e of the magnetic sensor module 4 output detection signals P4a and P4b that change according to the detected magnetic field, and input to the negative input terminal and the positive input terminal of the differential amplifier 8b of the drive detection IC 8, respectively. Is done.

  The electrode 5a of the Hall element 5 as a magnetic sensor element for detecting the geomagnetism in the Z-axis direction receives the drive voltage P1 from the drive detection IC 8, and the electrode 5d is connected to the negative power source Vss. The electrodes 5b and 5c of the Hall element 5 output detection signals P5a and P5b that change according to the detection magnetic field, and are input to the negative input terminal and the positive input terminal of the differential amplifier 8c of the drive detection IC 8, respectively. . The differential amplifier 8a outputs a magnetic signal Px as magnetic information that changes according to the geomagnetism intensity in the X-axis direction, and the differential amplifier 8b changes according to the geomagnetism intensity in the Y-axis direction. A magnetic signal Py is output as magnetic information, and the differential amplifier 8c outputs a magnetic signal Pz as magnetic information that changes in accordance with the strength of geomagnetism in the Z-axis direction. These magnetic signals Px, Py, and Pz are connected to any of the through-hole electrodes 2a to 2h that function as terminal electrodes, and are output to the outside. Further, the positive power source Vdd and the negative power source Vss are similarly input to the magnetic orientation detection device 1 via any one of the through-hole electrodes 2a to 2h and serve as a power source for the drive detection IC 8.

  Next, the operation of the magnetic orientation detection device 1 will be described. In FIG. 4, when power is supplied to the magnetic azimuth detecting device 1 by the plus power source Vdd and the minus power source Vss, the drive detection IC 8 starts to operate, and the DC power source 8g outputs the drive voltage P1. The drive voltage P1 is applied to the Hall element 10 incorporated in the magnetic sensor modules 3 and 4 and the bare Hall element 5 that detects a magnetic field in the Z-axis direction, and a drive current flows. As a result, each Hall element outputs a detection signal that changes according to the strength of geomagnetism due to the Hall effect. That is, the Hall element 10 of the magnetic sensor module 3 that detects the geomagnetism in the X-axis direction outputs detection signals P3a and P3b, and the Hall element 10 of the magnetic sensor module 4 that detects the geomagnetism in the Y-axis direction detects the detection signals P4a and P4b. The Hall element 5 that detects geomagnetism in the Z-axis direction outputs detection signals P5a and P5b.

  The drive detection IC 8 inputs the detection signals P3a and P3b from the magnetic sensor module 3, the detection signals P4a and P4b from the magnetic sensor module 4, and the detection signals P5a and P5b from the Hall element 5, respectively. Amplified by the dynamic amplifiers 8a, 8b, and bc, and outputs magnetic signals Px, Py, and Pz as analog quantities.

  Next, the detection characteristic with respect to the geomagnetism of the magnetic bearing detection device 1 will be described with reference to FIG. In FIG. 5 (a), the X-axis direction (arrow X) of the magnetic azimuth detecting device 1 is fixed at 0 degree (that is, substantially north) with respect to the geomagnetism C, and the Z-axis direction (arrow Z). Is fixed perpendicular to the geomagnetism C (that is, in the vertical direction). Next, as described above, power is supplied to the magnetic azimuth detecting device 1 and the operation is started. Here, since the magnetic sensor module 3 that detects the geomagnetic component in the X-axis direction is located in front of the geomagnetism C, the level of the magnetic signal Px is maximized. Further, since the magnetic sensor module 4 that detects the geomagnetic component in the Y-axis direction is positioned at 90 degrees with respect to the geomagnetism C, the level of the magnetic signal Py is minimized. In addition, since the Hall element 5 that detects the geomagnetic component in the Z-axis direction is also positioned at 90 degrees with respect to the geomagnetism C, the level of the magnetic signal Pz is minimized.

  Next, when the magnetic azimuth detecting device 1 is rotated 90 degrees in the direction of arrow D about the Z-axis direction (arrow Z), the magnetic sensor module 3 for detecting the geomagnetic component in the X-axis direction Since the position changes in the direction of 90 degrees, the level of the magnetic signal Px is minimized. Further, since the position of the magnetic sensor module 4 that detects the geomagnetic component in the Y-axis direction changes in front of the geomagnetism C, the level of the magnetic signal Py is maximized. Further, since the Hall element 5 that detects the geomagnetic component in the Z-axis direction maintains the 90 degree orientation with respect to the geomagnetism C, the level of the magnetic signal Pz is kept at the minimum. As described above, when the magnetic azimuth detecting device 1 is continuously rotated in the direction of the arrow D, the magnetic signals Px and Py of the magnetic sensor modules 3 and 4 continuously change according to the movement of the rotation angle.

  FIG. 5B shows that the magnetic azimuth detecting device 1 is continuously rotated in the direction of the arrow D from 0 degree with respect to the geomagnetism C, and the detection signals P3a, P3b, P4a, P4b of the magnetic sensor modules 3 and 4 are It is the graph which plotted the change of the magnetic signals Px and Py obtained by amplifying with the drive detection IC8 with respect to the rotation angle. In FIG. 5B, the X axis indicates the rotation angle of the magnetic azimuth detector 1 with respect to the geomagnetism C, and the Y axis indicates the relative output levels of the magnetic signals Px and Py.

  Here, paying attention to the magnetic signal Px output from the magnetic sensor module 3 that detects the geomagnetism in the X-axis direction, the magnetic azimuth detecting device 1 has a positive maximum value at a position of 0 degrees with respect to the geomagnetism C as described above. At 90 degrees, the minimum value is zero. Further, when the magnetic azimuth detecting device 1 is rotated in the direction of arrow D and the position of 180 degrees with respect to the geomagnetism C, the direction of the geomagnetism C is opposite to the position of 0 degrees with respect to the magnetic sensor module 3, so that the magnetic signal Px. Is negative and maximum. Further, when the magnetic sensor module 3 is rotated in the direction of the arrow D at a position of 270 degrees, the magnetic sensor module 3 is again at a position of 90 degrees with respect to the geomagnetism C. Therefore, the magnetic signal Px becomes the minimum value zero. Further, at a position of 360 degrees after further rotation, the magnetic signal Px has a positive maximum value equal to the initial rotation angle of 0 degrees.

  Further, when focusing attention on the magnetic signal Py output from the magnetic sensor module 4 that detects the geomagnetism in the Y-axis direction, as described above, the magnetic azimuth detecting device 1 has a minimum value of zero at a position of 0 degrees with respect to the geomagnetism C. At 90 degrees, the maximum value is positive. Further, when the magnetic azimuth detecting device 1 is rotated in the direction of the arrow D and the position is 180 degrees with respect to the geomagnetism C, the magnetic signal Py again becomes the minimum value of zero. Further, at the position of 270 degrees by rotating in the direction of the arrow D, the direction of the geomagnetism C is opposite to the position of 90 degrees with respect to the magnetic azimuth detecting device 1, so that the magnetic signal Py becomes a negative maximum value. Further, at a position of 360 degrees after further rotation, the magnetic signal Py has a minimum value of zero, which is equal to the initial rotation angle of 0 degrees. Further, although not shown, the magnetic signal Pz that is the output of the Hall element 5 that detects the geomagnetism in the Z-axis direction when the magnetic direction detection device 1 is rotated in the direction of arrow D is not shown. Since the direction (arrow Z) holds an angle of 90 degrees with respect to the geomagnetism C, the minimum value of zero is held.

  Next, based on FIG. 6, the magnetic signal Px that is the output of the magnetic sensor module 3 that detects the geomagnetism in the X-axis direction when the magnetic bearing detection device 1 is rotated about the Y-axis direction, and the Z-axis direction The change of the magnetic signal Pz, which is the output of the Hall element 5 that detects the geomagnetism, will be described. FIG. 6A is a side view of the magnetic azimuth detecting device 1 as viewed from the Y-axis direction. As an initial position, similarly to FIG. 5A, the X-axis direction (arrow X) of the magnetic azimuth detecting device 1 is shown. Is fixed at 0 degree with respect to the geomagnetism C (that is, in the direction of substantially north), and the Z-axis direction (arrow Z) is fixed perpendicularly with respect to the geomagnetism C (that is, in the vertical direction).

  Here, since the magnetic sensor module 3 for detecting the geomagnetism in the X-axis direction is located in front of the geomagnetism C, the level of the magnetic signal Px is maximized. Further, since the magnetic sensor module 4 for detecting the geomagnetism in the Y-axis direction is positioned at 90 degrees with respect to the geomagnetism C, the level of the magnetic signal Py is minimized. Further, since the Hall element 5 that detects the geomagnetism in the Z-axis direction is also positioned in a direction perpendicular to the geomagnetism C, the level of the magnetic signal Pz is minimized.

  Next, as shown in the figure, the magnetic azimuth detector 1 is rotated 90 degrees in the direction of arrow E about the Y-axis direction, and the Z-axis direction (arrow Z) of the magnetic azimuth detector 1 is 0 degrees with respect to the geomagnetism C. To be. Here, since the magnetic sensor module 3 for detecting the geomagnetism in the X-axis direction is positioned at 90 degrees downward with respect to the geomagnetism C, the level of the magnetic signal Px is minimized. Further, since the magnetic sensor module 4 that detects the geomagnetism in the Y-axis direction holds the 90 degree orientation with respect to the geomagnetism C, the level of the magnetic signal Py also holds the minimum. In addition, since the Hall element 5 that detects geomagnetism in the Z-axis direction is located in front of the geomagnetism C (that is, at an angle of 0 degrees), the level of the magnetic signal Pz is maximized. As described above, when the magnetic azimuth detecting device 1 is continuously rotated in the direction of the arrow E about the Y-axis direction, the magnetic signal Px of the magnetic sensor module 3 and the magnetic signal Pz of the Hall element 5 are set at the rotation angle. It changes continuously in response.

  FIG. 6B shows a case where the magnetic azimuth detecting device 1 is continuously rotated in the direction of the arrow E from 0 degree with respect to the geomagnetism C, and the detection signals P3a and P3b of the magnetic sensor module 3 and the detection signal of the Hall element 5 are detected. It is the graph which plotted the change of the magnetic signals Px and Pz obtained by amplifying P5a and P5b with the drive detection IC8 with respect to the rotation angle. In FIG. 6B, the X axis indicates the rotation angle of the magnetic azimuth detecting device 1 with respect to the geomagnetism C about the Y axis direction, and the Y axis indicates the relative output levels of the magnetic signals Px and Pz. Yes.

  Here, paying attention to the magnetic signal Px output from the magnetic sensor module 3 that detects the geomagnetism in the X-axis direction, as described above, when the X-axis direction of the magnetic azimuth detecting device 1 is 0 degrees with respect to the geomagnetism C, it is positive. At the position rotated 90 degrees in the direction of arrow E, the minimum value is zero. Further, when the magnetic azimuth detecting device 1 is rotated in the direction of arrow E and the X-axis direction is 180 degrees with respect to the geomagnetism C, the direction of the geomagnetism C is opposite to the position of 0 degrees with respect to the magnetic sensor module 3. Therefore, the magnetic signal Px is negative and has a maximum value. Further, when the magnetic sensor module 3 is rotated in the direction of the arrow E at a position of 270 degrees, the magnetic sensor module 3 is again at a position of 90 degrees with respect to the geomagnetism C, so the magnetic signal Px has a minimum value of zero. Further, at a position of 360 degrees after further rotation, the magnetic signal Px has a positive maximum value equal to the initial rotation angle of 0 degrees.

  When attention is paid to the magnetic signal Pz output from the Hall element 5 that detects the geomagnetism in the Z-axis direction, the minimum value is obtained when the X-axis direction of the magnetic azimuth detecting device 1 is 0 degree with respect to the geomagnetism C as described above. At the position rotated 90 degrees in the direction of arrow E, the maximum value is positive. Further, when the magnetic azimuth detecting device 1 is rotated in the direction of arrow E and the X-axis direction is at a position of 180 degrees with respect to the geomagnetism C, the magnetic signal Pz again becomes the minimum value of zero. Further, in the position of 270 degrees by rotating in the direction of arrow E, the direction of the geomagnetism C is opposite to the position of 90 degrees with respect to the magnetic azimuth detecting device 1, so that the magnetic signal Pz is negative and has a maximum value. Further, at a position of 360 degrees after further rotation, the magnetic signal Pz has a minimum value of zero, which is equal to the initial rotation angle of 0 degrees. Further, although not shown, a magnetic signal Py that is an output of the magnetic sensor module 4 that detects geomagnetism in the Y-axis direction when the magnetic direction detection device 1 is rotated in the direction of the arrow E is not shown. Since it rotates while always maintaining an angle of 90 degrees with respect to the axial direction, its output level is kept at the minimum value of zero.

  When the magnetic azimuth detecting device 1 is rotated about the X-axis direction, the magnetic signals Py and Pz change according to the rotation angle, but the characteristics are the same as in FIG. . The actual magnetic signals Px, Py, and Pz are always affected by the holding magnetic field inside the portable device or the like in which the magnetic azimuth detecting device 1 is incorporated. The value needs to be cancelled. The maximum values of the magnetic signals Px, Py, and Pz shown in FIGS. 5B and 6B depend on the magnitude of the detected geomagnetism, but both the maximum values in the positive direction and the negative direction are the same. The relative values are set to plus 1 and minus 1.

  Thus, from the graph of FIG. 5B, the values of the magnetic signal Px representing the geomagnetism intensity in the X-axis direction and the magnetic signal Py representing the geomagnetism intensity in the Y-axis direction of the magnetic azimuth detecting device 1 are obtained. By knowing, it is possible to know the rotation angle of the magnetic azimuth detecting device 1 with respect to the geomagnetism C, and as a result, it is possible to obtain an azimuth based on the geomagnetism C. However, there is no problem as long as the Z-axis direction of the magnetic azimuth detecting device 1 is always kept perpendicular to the geomagnetism C, but the user of the portable information device incorporating the magnetic azimuth detecting device 1 holds the portable information device horizontally. If it is used tilted with respect to the direction, an error occurs in the direction measurement.

  That is, as apparent from FIG. 6B, when the Z-axis direction of the magnetic azimuth detecting device 1 is tilted with respect to the geomagnetism C, the magnetic signal Px in the X-axis direction becomes large according to the magnitude of the tilt. fluctuate. For this reason, it can be understood that accurate azimuth measurement cannot be performed with magnetic information of only the two axes of the magnetic signal Px in the X-axis direction and the magnetic signal Py in the Y-axis direction. However, since the magnetic azimuth detecting device of the present invention has the Hall element 5 that detects the geomagnetism in the Z-axis direction, the tilt angle in the Z-axis direction is determined from the value of the magnetic signal Pz that is the output of the Hall element 5. By calculating and correcting the magnetic signals Px and Py according to the tilt angle in the Z-axis direction, even if the magnetic bearing detection device 1 has a tilt with respect to the Z-axis direction, the bearing can be measured with high accuracy. Is possible.

  As described above, according to the magnetic azimuth detecting device of the present invention, the magnetic sensor modules 3 and 4 that detect the geomagnetic component in the X-axis direction and the Y-axis direction, and the magnetic sensor element that detects the geomagnetic component in the Z-axis direction. The Hall element 5 and the drive detection IC 8 for driving these magnetic sensor elements to detect the magnetism can be mounted on the circuit board 2 and integrated. Further, since all the magnetic detection means in the X-axis direction, the Y-axis direction, and the Z-axis direction use Hall elements made of semiconductors that do not require coils or cores, the magnetic orientation detection device can be further reduced in size. . That is, the outer size of the magnetic sensor modules 3 and 4 for detecting the geomagnetism in the X-axis direction and the Y-axis direction is as small as about 2.8 mm × 0.6 mm as described above, and the Hall element for detecting the geomagnetism in the Z-axis direction. 5 and the drive detection IC 8 are directly bare-mounted on the circuit board 2, so that the outer size of the magnetic orientation detection device 1 can be realized as an example of 5.9 mm × 6.3 mm and a height of about 1 mm.

  In addition, since the magnetic sensor modules 3 and 4 are mounted on the circuit board 2 by lead-free solder, a magnetic orientation detection device that does not have to worry about environmental pollution due to lead can be provided. Furthermore, since the magnetic sensor modules 3 and 4 are mounted on the circuit board 2 with low-residue solder, cleaning after reflow is unnecessary, and it is possible to prevent solder from being blown out in the moisture absorption reflow test. Therefore, open shoot defects due to solder are reduced, and a highly reliable magnetic direction detecting device can be provided.

  Further, the magnetic orientation detection device 1 is efficiently mounted and incorporated by surface mounting on a substrate of a portable information device such as a cellular phone (not shown) by through-hole electrodes 2a to 2h arranged around the circuit substrate 2. In addition, since the geomagnetism is detected by the three axes of the X-axis direction, the Y-axis direction, and the Z-axis direction, even if the magnetic azimuth detector is tilted with respect to the geomagnetism, A geomagnetic measurement value can be corrected, and a highly accurate bearing detection device can be provided. In addition, since the Hall element can detect a magnetic field only by supplying a direct current, the configuration of the drive detection IC 8 for driving the Hall element is simple, and a low-cost magnetic orientation detection device can be realized.

  Next, the configuration of the magnetic bearing detection apparatus of the present invention as Example 2 will be described with reference to FIG. The second embodiment has a configuration in which calculation means for calculating the direction is incorporated and integrated. The same elements as those in the first embodiment are denoted by the same reference numerals, and a part of overlapping description is omitted. In FIG. 7, reference numeral 20 denotes a magnetic azimuth detecting device according to the second embodiment of the present invention. The circuit board 2 as the substantially rectangular insulating substrate is preferably made of a heat-resistant glass epoxy substrate, a ceramic substrate, or the like, and has a thickness of about 0.3 mm.

  The magnetic sensor module 3 is mounted by solder (not shown) or the like so as to detect the geomagnetic component in the X-axis direction (arrow X) of the plane of the circuit board 2 as in the first embodiment. It is mounted by solder (not shown) or the like so as to detect the geomagnetic component in the Y-axis direction (arrow Y) rotated 90 degrees with respect to the mounting direction of the magnetic sensor module 3 on the plane of the circuit board 2. The magnetic sensor modules 3 and 4 are preferably mounted with lead-free solder or low-residue solder as in the first embodiment. The Hall element 5 is bare-mounted on the circuit board 2 by wire bonding so as to detect a geomagnetic component in the Z-axis direction that is perpendicular to the plane of the circuit board 2.

  A drive detection IC 8 that drives the magnetic sensor modules 3 and 4 and the Hall element 5 to amplify a detection signal is bare-mounted on the circuit board 2 by wire bonding. Reference numeral 21 denotes a small-scale microcomputer (hereinafter abbreviated as a microcomputer) as arithmetic means, which is flip-chip mounted on the circuit board 2. Flip chip mounting is effective for reducing the mounting area, but is not limited to this mounting method. Therefore, the microcomputer 21 is mounted on the circuit board 2 together with the magnetic sensor modules 3 and 4, the hall element 5, and the drive detection IC 8, and is sealed and integrated by a sealing member (not shown).

  The through-hole electrodes 2a to 2h as terminal electrodes arranged around the circuit board 2 are formed up to a part of the back surface of the circuit board 2 (not shown) and function as terminal electrodes electrically connected to the outside. To do. That is, when the magnetic orientation detection device 20 is incorporated into a portable device or the like, it can be surface-mounted with solder or the like using the through-hole electrodes 2a to 2h. Although the number of the through-hole electrodes 2a to 2h is eight in this embodiment, the number is not limited to this number, and may be increased or decreased according to the specification. Moreover, the terminal electrode of the magnetic direction detection apparatus 20 is not limited to the form of the through-hole electrodes 2a to 2h, and may be any form of terminal electrode.

  As described above, the magnetic orientation detection device 20 includes the magnetic sensor modules 3 and 4, the hall element 5, the drive detection IC 8, and the microcomputer 21 mounted on the circuit board 2, and a sealing member (not shown). Sealed and integrated. The magnetic orientation detection device 20 is efficiently mounted and incorporated by surface mounting on a substrate of a portable information device such as a cellular phone (not shown) by the through-hole electrodes 2a to 2h arranged around the circuit board 2.

  Next, a circuit configuration of the magnetic orientation detection device 20 according to the second embodiment will be described with reference to FIG. The same elements as those in the first embodiment are denoted by the same reference numerals, and a part of overlapping description is omitted. In FIG. 8, the entire block surrounded by a broken line is the magnetic direction detection device 20. The drive detection IC 8 outputs a drive voltage P 1 and supplies a drive current to the magnetic sensor modules 3 and 4 and the Hall element 5. Further, the drive detection IC 8 inputs detection signals P3a and P3b from the magnetic sensor module 3, detection signals P4a and P4b from the magnetic sensor module 4, and detection signals P5a and P5b from the Hall element 5, and an internal difference It amplifies by the dynamic amplifiers 8a-8c and outputs magnetic signals Px, Py, Pz as magnetic information.

  Although not shown in the figure, the microcomputer 21 as a calculation means includes an A / D converter, a calculation circuit, a storage circuit, and the like, and inputs magnetic signals Px, Py, and Pz as magnetic information from the drive detection IC 8. To calculate the azimuth and output the azimuth data Po, which is a digitized serial signal, to the outside. The positive power source Vdd and the negative power source Vss are connected to the drive detection IC 8 and the microcomputer 21, respectively, to supply power. The orientation data Po, the positive power source Vdd, the negative power source Vss, etc. connected to the outside are connected to any of the through-hole electrodes 2a to 2h as terminal electrodes shown in FIG. It can be arbitrarily determined according to the wiring pattern of the substrate 2.

  As described above, the magnetic azimuth detecting device 20 according to the second embodiment of the present invention is integrated with the microcomputer 21 that inputs the magnetic information in the X-axis direction, the Y-axis direction, and the Z-axis direction and calculates the azimuth. Therefore, digitized azimuth data can be output directly. As a result, a portable information device such as a mobile phone that incorporates the magnetic azimuth detecting device 20 does not need to calculate azimuth data by an internal calculation means. As a whole, it is possible to provide information equipment with excellent processing capability. In addition, since the processing load of the system is reduced, it is possible to select a computing means with a low processing capability, which is useful for realizing a portable information device with a long battery life and excellent cost performance.

  In the second embodiment of the present invention, the drive detection IC 8 and the microcomputer 21 are separate components. However, the present invention is not limited to this configuration, and the drive detection IC 8 and the microcomputer 21 may be configured as a one-chip IC. The microcomputer 21 executes arithmetic processing and the like with firmware stored therein, but is not limited to this configuration, and may be configured with hardware such as a custom IC instead of the microcomputer 21. Further, although the orientation data Po is serial data, it may be 4-bit parallel data.

  In addition, although the method of manufacturing the magnetic direction detecting device of the present invention is not shown, through holes are formed in the collective substrate, and after mounting components, dicing is performed along the through holes, whereby a large number of circuit boards can be completed. . As a result, it is possible to provide a magnetic azimuth detecting device that is excellent in mass productivity and stable in quality. In each embodiment of the present invention, the magnetic sensor element for detecting the geomagnetic component in the Z-axis direction is barely mounted on the circuit board. However, the present invention is not limited to this mounting method. For example, although not shown, the magnetic sensor element for detecting the geomagnetic component in the Z-axis direction is mounted on the sensor substrate in the same manner as the magnetic sensor element for detecting the geomagnetic component in the X-axis direction and the Y-axis direction. A module may be formed and mounted on a circuit board by solder mounting. As a result, the magnetic sensor elements for detecting the X-axis direction, the Y-axis direction, and the Z-axis direction are mounted on the circuit board by the magnetic sensor module in the same mounting method, so that the number of mounting steps can be reduced.

It is a top view of the magnetic direction detection apparatus of Example 1 of this invention. It is a perspective view of the magnetic direction detection apparatus of Example 1 of this invention. It is a front perspective view of the magnetic sensor module mounted in the magnetic direction detection apparatus of this invention. It is an upper surface mounting figure of the magnetic sensor module mounted in the magnetic orientation detection apparatus of this invention. It is a side surface mounting view of the magnetic sensor module mounted in the magnetic direction detection apparatus of this invention. It is a circuit block diagram of the magnetic direction detection apparatus of Example 1 of this invention. It is explanatory drawing explaining the geomagnetic detection characteristic measurement of the X-axis direction of the magnetic azimuth | direction detection apparatus of this invention, and a Y-axis direction. It is a geomagnetic detection characteristic graph of the X-axis direction of the magnetic azimuth | direction detection apparatus of this invention, and a Y-axis direction. It is explanatory drawing explaining the geomagnetic detection characteristic measurement of the X-axis direction of a magnetic azimuth | direction detection apparatus of this invention, and a Z-axis direction. It is a geomagnetic detection characteristic graph of the X-axis direction of the magnetic azimuth | direction detection apparatus of this invention, and a Z-axis direction. It is a top view of the magnetic direction detection apparatus of Example 2 of this invention. It is a circuit block diagram of the magnetic direction detection apparatus of Example 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,20 Magnetic orientation detection apparatus 2 Circuit board 2a-2h Through-hole electrode 3, 4 Magnetic sensor module 3a Sensor board 3b Adhesive paste 3c-3f Electrode 3g, 6a, 6b Wire 3h, 9 Sealing member 5, 10 Hall element 7a, 7b Connection electrode 8 Drive detection IC
8a-8c Differential amplifier 8d-8f Resistance 8g DC power supply 11a-11d Conductive pattern 12a-12d Solder 13a-13c Resist pattern 21 Microcomputer P1 Drive voltage P3a, P3b, P4a, P4b, P5a, P5b Detection signal Px, Py, Pz Magnetic signal Po Direction data Vdd Positive power supply Vss Negative power supply

Claims (5)

A plurality of magnetic sensor elements and a plurality of magnetic sensor elements are driven on an insulating substrate having a plurality of terminal electrodes for electrical connection with the outside, and detection signals from the plurality of magnetic sensor elements are input. And a semiconductor that outputs magnetic information according to the strength of the magnetism,
The two magnetic sensor elements for detecting a geomagnetic component in the horizontal direction with respect to the insulating substrate are mounted on the sensor substrate to form a magnetic sensor module, and the magnetic sensor module is mounted on the insulating substrate by solder mounting. The other magnetic sensor element that is mounted and detects a geomagnetic component in a direction perpendicular to the insulating substrate is bare-mounted on the insulating substrate,
A magnetic orientation detection device, wherein the magnetic sensor module, another magnetic sensor element, and the semiconductor are integrated by sealing with a sealing member. A plurality of magnetic sensor elements and a plurality of magnetic sensor elements are driven on an insulating substrate having a plurality of terminal electrodes for electrical connection with the outside, and detection signals from the plurality of magnetic sensor elements are input. A semiconductor that outputs magnetic information according to the strength of the magnetic field, and an arithmetic means for calculating the azimuth by inputting the magnetic information from the semiconductor,
The two magnetic sensor elements for detecting a geomagnetic component in the horizontal direction with respect to the insulating substrate are mounted on the sensor substrate to form a magnetic sensor module, and the magnetic sensor module is mounted on the insulating substrate by solder mounting. The other magnetic sensor element that is mounted and detects a geomagnetic component in a direction perpendicular to the insulating substrate is bare-mounted on the insulating substrate,
A magnetic orientation detection device, wherein the magnetic sensor module, another magnetic sensor element, the semiconductor, and the arithmetic means are sealed and integrated with a sealing member. One of the magnetic sensor modules detects a geomagnetic component in the X-axis direction of the plane of the insulating substrate, and the other magnetic sensor module has a Y-axis direction having an angle of 90 degrees with respect to the X-axis direction. The other magnetic sensor element is arranged so as to detect a geomagnetic component in the Z-axis direction that is perpendicular to the plane in the X-axis direction and the Y-axis direction. The magnetic azimuth detecting device according to claim 1 or 2. 4. The magnetic orientation detection device according to claim 1 , wherein the magnetic sensor module is mounted on the insulating substrate by lead-free solder. Wherein the plurality of magnetic sensor elements, magnetic azimuth detecting device according to any one of claims 1 to 4, characterized in that a Hall element.

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