KR101090967B1 - Electronic compass and method of fabricating the same - Google Patents

Abstract

PURPOSE: An electron compass, which extracts 3D-coordinate by detecting earth magnetism, and a manufacturing method of the same are provided to perform vector extraction action by compensating components of each direction. CONSTITUTION: An electron compass, which extracts 3D-coordinate by detecting earth magnetism comprises a first direction magnetic sensor and a second direction magnetic sensor. The first direction magnetic sensor extracts the first direction magnetism component of vector by including the first magnetic material expanded as the first direction. Both end of the second direction magnetic sensor is inward bent by 45°~90°. The electric compass surrounds the bent both ends of the first and second magnetic material and includes the drive coil supplying the alternating current. The pickup coil measuring the voltage change based on the alternating current.

Description

Electronic compass and method of fabricating the same

The present invention relates to an electronic compass, and more particularly, to an electronic compass and a method for manufacturing the electronic compass to extract the three-dimensional coordinates by detecting the geomagnetic.

A geomagnetic sensor can function as an electronic compass by measuring the strength of the earth's magnetic field, calculating the azimuth angle. To implement the electronic compass function, three-axis geomagnetic sensors with X, Y, and Z axes perpendicular to each other are required.

In the detection of the vector components of the geomagnetic intensity on each sensor axis based on three vertically arranged geomagnetic sensors, measuring the geomagnetism of the X, Y and Z axes of the Cartesian coordinate system by a sensor having substantially the same sensitivity is the correct coordinate. Easy to extract

Since three-axis geomagnetic sensors are mounted in portable devices, the two-axis geomagnetic sensor is a sensor in which two axes of geomagnetic sensors are arranged perpendicularly to each other in the X and Y planes, such as fluxgate and MR ( Various types of sensors such as magneto-resistance (MI) and magneto-impedance (MI) can be mounted, and the other one axis can adopt a different type of sensor to form a three-axis hybrid type electronic compass. For example, the two axes of the sensor may use a fluxgate type, and the other one of the axes may reduce the vertical height of the electronic compass by using an MR sensor or a hall sensor.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide an electronic compass and a method of manufacturing the same, which may be implemented in a small size by improving the structure of the flux gate sensor constituting the geomagnetic sensor.

Another technical problem to be achieved by the present invention is to provide an electronic compass and a method of manufacturing the flux gate sensor which can be arranged to surround the hall sensor to improve the reliability of geomagnetic sensing.

Another object of the present invention is to provide an electronic compass and a method of manufacturing the same, which can perform a reliable vector extraction operation by mounting a plurality of sensors inside the electronic compass of the same size.

An electronic compass according to an embodiment of the present invention includes a first magnetic body extending in a first direction to extract a first direction magnetic vector component, and both ends of the first magnetic body are connected to the first direction. A second direction magnetic vector component having a first direction magnetic sensor having a 'c' shape bent inwardly at an angle of 45 ° to 90 ° toward a second vertical direction, and a second magnetic body extending in the second direction; To extract, both ends of the second magnetic body includes a second direction magnetic sensor having a '' 'shape bent in the 45 ° to 90 ° inward toward the first direction.

An electronic compass according to another embodiment of the present invention is formed on a substrate and includes a first pick-up region extending in a first direction and a first driving region extending in a second direction perpendicular to the first direction. A first direction magnetic sensor having a magnetic material and extracting a first direction magnetic vector component, a second pickup region formed on the substrate and extending in the second direction and a second driving region extending in the first direction; A second directional magnetic sensor having a second magnetic body including a second directional magnetic vector component, and a magnetic vector component in a third direction formed at the center of the substrate and perpendicular to the first and second directions; And a Hall sensor for extracting, wherein the Hall sensor is disposed to be surrounded by the first and second directional magnetic sensors.

An electronic compass comprising a first direction magnetic sensor for extracting a vector component in a first direction and a second direction magnetic sensor for extracting a vector component in a second direction perpendicular to the first direction according to another embodiment of the present invention. A manufacturing method, comprising: forming a first ferromagnetic material included in the first direction magnetic sensor by applying a magnetic field in the second direction, and applying the magnetic field in the first direction to include in the second direction magnetic sensor Forming a second ferromagnetic material.

The electronic compass and its manufacturing method according to an embodiment of the present invention can be implemented in a small size by improving the structure of the flux gate sensor constituting the geomagnetic sensor is suitable for a portable device.

An electronic compass and a method for manufacturing the same according to another embodiment of the present invention provide a electronic compass and a method for manufacturing the same, in which a flux gate sensor is disposed to surround the hall sensor, thereby minimizing interference due to the geomagnetic.

According to another embodiment of the present invention, an electronic compass and a method of manufacturing the same may be equipped with a plurality of sensors that extract vector components in one direction inside the electronic compass to compensate components in each direction to perform a reliable vector extraction operation. have.

1 is a conceptual diagram for describing an operation of a flux gate sensor.
2A to 4B are diagrams for explaining a principle of measuring a coordinate of a flux gate sensor.
5A to 5C are diagrams for describing magnitudes of measured voltages according to lengths of ferromagnetic materials in a flux gate sensor.
6A is a diagram illustrating an electronic compass including magnetic sensors arranged in a conventional X and Y axes.
6B to 6D are diagrams illustrating an electronic compass according to embodiments of the present invention.
7A and 7B are diagrams for describing an output voltage measuring capability of a magnetic sensor according to an exemplary embodiment of the present invention.
8 is a diagram illustrating a hall sensor which extracts a vector component in the Z axis direction.
9 and 10 are diagrams illustrating an electronic compass according to an embodiment of the present invention.
FIG. 11 is a conceptual diagram for describing a method of calculating actual coordinates by a coordinate extracting unit based on vector components of each direction extracted by the electronic compass of FIG. 10.
12 is a diagram illustrating an electronic compass according to an embodiment of the present invention.
13A to 13J are views illustrating a method of manufacturing an electronic compass according to an embodiment of the present invention.
FIG. 14A is an electronic compass implemented in a package further including an application-specific integrated circuit (ASIC) for driving the electronic compass after two-dimensional magnetic sensors are formed based on the processes shown in FIGS. 13A to 13J. 14B is a sectional view taken along the line BB 'of FIG. 14A.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a conceptual diagram for describing an operation of a flux gate sensor.

Referring to FIG. 1, the flux gate sensor 10 may include a ferromagnetic material 11, a driving coil 12, and a pick up coil 13.

The flux gate sensor 10 operates in a manner in which the pickup coil 12 measures a voltage generated according to a magnetic field induced in the ferromagnetic material 11 by an alternating current provided through the driving coil 12.

The ferromagnetic material 11 may include iron (Fe), cobalt (Co), nickel (Ni), and alloys thereof, and atoms are arranged and magnetized in a predetermined direction under the influence of an external magnetic field. Since the magnetization direction of the ferromagnetic material 11 is different depending on the current by the drive coil 12, when an alternating current is provided through the drive coil 12, the magnetization direction inside the ferromagnetic material 11 according to the cycle of the alternating current. This is reversed. When the magnetization direction is reversed, a peak voltage is generated and measured by the pickup coil 12.

2A to 4B are diagrams for explaining a principle of measuring a coordinate of a flux gate sensor.

FIG. 2A shows the flux gate sensor placed in the east-west direction, and FIG. 2B shows the voltage output waveform measured by the pickup coil when the flux gate sensor is placed as shown in FIG. 2A.

FIG. 3A illustrates a flux gate sensor placed in the north-south direction, and FIG. 3B illustrates a voltage output waveform measured by the pickup coil when the flux gate sensor is placed as shown in FIG. 3A.

4A shows the flux gate sensor lying in the north-south direction, and FIG. 4B shows the voltage output waveform measured by the pickup coil when the flux gate sensor is placed as shown in FIG. 4A.

In Figures 2a, 3a and 4a R represents a reference point. The orientation of the reference point R may be calculated based on the voltage measured at the pickup coil. In FIGS. 2A-4B, the alternating current provided to each flux gate sensor has substantially the same amplitude and period.

Referring to FIG. 2B, when the flux gate sensor is placed in the east-west direction, the magnetization direction inside the ferromagnetic material 10 is inverted based on an alternating current of a sine wave or triangle wave applied by the driving coil. At the time when the magnetization direction is reversed, a peak voltage is measured at the pickup coil. The magnitude of the peak voltage can be calculated as follows.

[Equation 1]

In Equation 1, K is a constant, M is the value of the magnetic field, t is time, and V is the measured voltage value. A magnetic field according to the measured voltage value may be calculated based on Equation 1.

Referring to FIG. 3B, in the case where the magnetization direction is reversed twice, in the north-south direction, the magnetization reversal occurs at a time slower than the east-west direction, and the magnetization reversal occurs at a time earlier than the east-west direction. .

Referring to FIG. 4B, in two cases in which the magnetization direction is reversed, in the north-south direction, magnetization reversal occurs at a time earlier than the east-west direction, and magnetization reversal occurs at a time later than the east-west direction.

By comparing the times of magnetization reversal and current magnetization reversal in a specific reference orientation as described above, the magnitude of the magnetic field currently applied to the flux gate sensor can be known, and when the flux gate sensor is positioned in the X and Y directions, The geomagnetism of can be measured to generate two-dimensional vector coordinates.

5A to 5C are diagrams for describing magnitudes of measured voltages according to lengths of ferromagnetic materials in a flux gate sensor.

5A is a conceptual diagram illustrating a magnetic force line of a ferromagnetic material magnetized by application of current. Referring to FIG. 5A, it can be seen that the magnetized ferromagnetic material has N poles and S poles, and magnetic force lines are distributed from the N pole to the S pole. However, the lines of magnetic force form a straight line only inside the ferromagnetic material, and form a curved line outside the ferromagnetic material 10. In particular, the magnetic lines of force are radially distributed in the region near the N pole and the S pole, so that the magnetic field in any specific direction cannot be set. As a result, demagnetizing regions are formed in the N pole and S pole regions, and even though alternating current flows, magnetization reversal of the ferromagnetic material 10 may interfere with the magnetization reversal.

In FIG. 5B, a region 1a in which magnetization reversal substantially occurs and a region 1b that interferes with magnetization reversal are shown along the length of the ferromagnetic material 10. In FIG. 5B, the area indicated by hatching is an area where magnetization reversal is difficult to occur, and only the area 1a not indicated by hatching is an area where magnetization reversal is easy to occur.

As the length of the ferromagnetic material 10 increases, the area 1a in which magnetization reversal may occur increases, and as shown in FIG. 5C, the larger the area 1a in which magnetization reversal occurs, the greater the magnitude of the measured voltage. When the region 1b in which magnetization reversal occurs is too narrow, as in the case of (c) of FIG. 5B, the magnitude of the peak voltage to be measured is also very small, and such a small peak voltage is caused by external leakage or adjacent voltage leakage. Due to noise caused by electromagnetic waves generated by electronic devices and peripheral circuits, it becomes difficult to determine the position of peak voltage in subsequent signal processing. Errors can occur in geomagnetic measurements. Therefore, in order to increase the reliability of geomagnetic measurement, it is necessary to increase the magnitude of the output peak voltage, and in order to do so, it is important to secure the area where magnetization reversal occurs inside the flux gate sensor 10 as wide as possible.

6A is a diagram illustrating an electronic compass including magnetic sensors arranged in a conventional X and Y axes.

Referring to FIG. 6A, the electronic compass 600a may include a first direction magnetic sensor 620a extending in the X axis direction and a second direction magnetic sensor 630a extending in the Y axis direction on the substrate 610a. Can be.

The substrate 610a may include a silicon substrate, silicon germanium (Si-Ge), a silicon-on-insulation (SOI) substrate, and a printed circuit base (PCB).

The first direction magnetic sensor 620a receives a voltage formed by an alternating current provided by the first driving coils d11 and d12 surrounding both ends of the ferromagnetic material m1. The first direction magnetic vector component may be extracted based on the measured voltage.

The second direction magnetic sensor 630a is a second pick-up coil p2 surrounding the center of the ferromagnetic material m2 and is applied to an alternating current provided by the second driving coils d21 and d22 surrounding both ends of the ferromagnetic material m2. By measuring the voltage formed by the second direction magnetic vector component can be extracted.

However, in FIG. 6A, the portion in which the magnetization direction is measured is a portion in which the first and second pickup coils p1 and p2 are wound, and the portion in which the driving coils d11, d12, d21, and d22 are wound. As a result, the length of the X axis and the Y axis of the electronic compass 600a is increased to increase the overall size.

6B to 6D are diagrams illustrating an electronic compass according to embodiments of the present invention.

In FIGS. 6B to 6D, the same reference numerals refer to the same elements, and detailed description thereof will be omitted.

Referring to FIG. 6B, the electronic compass 600b may include a substrate 610b, a first directional magnetic sensor 620b and a second directional magnetic sensor 630b formed on the substrate 610b.

6A, the first magnetic body m1 of the first direction magnetic sensor 620b extends in the X-axis direction, but both ends of the first magnetic body m1 are bent in the Y-axis direction. The second magnetic body m2 of the two-way magnetic sensor 630b also extends in the Y-axis direction, but both ends of the second magnetic body m2 are bent in the X-axis direction. The driving coils are wound around an area in which the first direction magnetic sensor 620b and the second direction magnetic sensor 630b are bent, and the area where voltage measurement by magnetization reversal is performed extends in the X-axis and Y-axis directions. Both ends of each of the magnetic bodies m1 and m2 are bent to face the same direction, and may be bent inward to reduce the size of the entire electronic compass 600b through the arrangement on the substrate 610b.

In the first directional magnetic sensor 620b and the second directional magnetic sensor 630b, the bent regions in which the driving coils d11, d12, d21, and d22 are wound may be larger than those in which the pickup coils p1 and p2 are wound. It may have a short length.

The first directional magnetic sensor 620b includes first driving coils d11 and d12 wound around both ends to provide an alternating current, and the first driving coils d11 and d12 are connected to each other. In addition, the first pickup coil p1 measuring the magnetization reversal by the first driving coils d11 and d12 is wound around the ferromagnetic region extending in the first direction. In addition, in order to assist in measuring the magnetization reversal of the first pickup coil p1, the first auxiliary coil is bent between an area where the first magnetic body m1 is bent, that is, between the first driving coils d11 and d12 and the first pickup coil p1. (c11, c12) may be further wound. The first auxiliary coils c11 and c12 are connected to the first driving coils d11 and d12 so that the magnetization direction due to the current provided from the first driving coils d11 and d12 is in the direction of the first pickup coil p1. Induce.

Accordingly, the electronic compass 600b according to the embodiment of the present invention maintains the pickup coils p1 and p2 so that the area where the voltage magnitude is measured is directed toward the first direction and the second direction, respectively, except for the driving coil. The area wound by (d11, d12, d21, d22) can be implemented in a small size by forming a curved shape.

The second direction magnetic sensor 630b has a structure substantially the same as the first direction magnetic sensor 620b except that the arrangement direction is perpendicular to the first direction magnetic sensor 620b.

That is, the second direction magnetic sensor 630b has a form in which the center portion extends in the second direction, and both ends include a second magnetic body m2 having a shape bent to face the first direction. The second pick-up coil p2 is wound around the portion extending in the second direction of m2, and the second drive coils d21 and d22 are wound around the portion extending in the first direction so that the second pick-up coil p2 is wound. While maintaining the second direction, the region in which the alternating current is provided may have a curved shape. In addition, the second auxiliary coils c21 and c22 are wound between the second pickup coil p2 and the second driving coils d21 and d22 on the second magnetic body m2 to provide a direction in which the driving current is provided in the second direction. Induce.

FIG. 6C has a structure similar to that of FIG. 6B, but indicates that an area where the driving coils of the first direction magnetic sensor 620c and the second direction magnetic sensor 630c are detected, that is, an angle at which both ends of the magnetic body are bent is 45 °. It features.

The electronic compasses 600b and 600c of FIGS. 6B and 6C have substantially the same structure except for the bent angles at both ends of the first and second directional magnetic sensors 620c and 630c.

The electronic compass 600c of FIG. 6C can reduce the size compared to the electronic compass 600a of FIG. 6A, and drive coils d11, d12, which are provided with a driving current as compared to the electronic compass 600b of FIG. 6B. Since the angle between d21 and d22 and the pickup coils p1 and p2 is small, the auxiliary coils c11, c12, c21 and c22 for inducing the direction of the alternating current provided from the drive coils d11, d12, d21 and d22. The number of turns can be reduced.

The electronic compasses 600b and 600c of FIGS. 6b and 6c may reduce the size of the two-dimensional electronic compass by bending the end portions of the driving coils for magnetizing the sensors at 45 ° to 90 °. . Since the direction of the portion where the pickup coil is wound is substantially the same, the effect of vector component extraction in each direction is substantially the same as that of the electronic compass 600a shown in FIG. 6A.

6D is characterized in that the first direction magnetic sensor 620d and the second direction magnetic sensor 630d have a shape of 'b'.

In FIG. 6D, the first direction magnetic sensor 620d may include a first magnetic body m1 having a 'b' shape including a pickup area extending in the first direction and a driving area extending in the second direction. The first pickup coil p1 may be wound around the pickup area, and the first driving coil d11 may be wound around the pickup area. In addition, the second direction magnetic sensor 630d may include a second magnetic body m2 having a 'b' shape, including a pickup area extending in a second direction and a driving area extending in a first direction. The second pickup coil p2 may be wound around the pickup area, and the second driving coil d21 may be wound around the pickup area.

The electronic compass 600d bends the magnetic body in a direction different from the region in which the pickup coils p1 and p2 extract the magnetic vector, thereby intensively arranging the driving coils d11 and d21 in one direction to increase the magnitude of the driving current. The auxiliary coils c1 and c2 may be included in the bent regions of the magnetic bodies m1 and m2 to guide the driving current toward the pickup coils p1 and p2. In addition, the driving coils d12 and d22 are also wound at the ends of the pick-up regions of the magnetic bodies m1 and m2 so that a magnetic field due to the driving current can be formed in the entire magnetic bodies m1 and m2 so that the pickup coils p1 and p2 This peak voltage can be measured.

The electronic compass 600d distinguishes the driving region forming the magnetic field from the pickup region measuring the voltage, and maintains the pickup region in a direction for measuring the direction, and may be implemented to have a small size by bending the driving region to be perpendicular to the measuring direction. .

In FIG. 6D, the driving region is illustrated to be perpendicular to the pickup region. However, in the electronic compass 600d according to the exemplary embodiment of the present invention, if the pickup region faces the first and second directions, respectively, the driving region may be the driving region. The bending angle may be 45 degrees to 90 degrees, and is not limited to that shown.

In the electronic compasses 600b, 600c, and 600d shown in Figs. 6B to 6D, the dotted lines indicate the size of the conventional electronic compass 600a. The electronic compasses 600b, 600c, and 600d according to an embodiment of the present invention may have a size of about 60 to 80% of the conventional electronic compass 600a, thereby miniaturizing it.

7A and 7B are diagrams for describing an output voltage measuring capability of a magnetic sensor according to an exemplary embodiment of the present invention. (a) shows the sensing voltage according to the length and magnetization reversal of the conventional flux gate sensor, (b) shows the sensing voltage when the length of the conventional flux gate sensor is reduced only, and (c) shows According to an embodiment, the length and the sensing voltage when the both ends of the magnetic material of the flux gate sensor are bent are shown.

In FIG. 7A, the length of the entire magnetic body of the conventional plus gate sensor is L1a, and the length of the region in which the driving coil is wound to provide an alternating current may be represented by 2 * L1c. The length of the region in which the pick-up coil is wound to measure the peak voltage when an alternating current is provided to magnetize the magnetic body and the magnetization reversal occurs may be represented by L1b. As described above with reference to FIGS. 5A to 5C, the longer the region where magnetization reversal can occur, the larger the magnitude of the peak voltage is, and the longer the length of the coil winding region is in proportion to the length. Increasing the area where the drive coil is wound increases, the intensity of the magnetic field inside the coil applied to the magnetic material through the drive coil increases, thereby increasing the magnitude of the output peak voltage, and the longer the area where the pickup coil is wound, The number of turns of the pickup coil can be increased, and the increase in the number of turns increases the magnitude of the peak voltage output along the pickup coil, so that the position of the peak voltage can be accurately determined through subsequent signal processing.

When the flux gate sensor has a length of L1b, the voltage of Vd1 is sensed by magnetization reversal.

(b) shows a case in which the entire length of the magnetic material is reduced to reduce the size of the flux gate sensor. The length of the entire flux gate sensor is also reduced to L2a, the length of the area where the drive coil is wound is reduced to 2 * L2c, and the length of the area where the pickup coil is wound to L1b. Accordingly, the magnitude of the driving current that causes magnetization is reduced and the area participating in the magnetization reversal is also reduced. Thus, in FIG. 8B, the magnitude of the measured peak voltage is reduced to Vd2.

In (c), the length of the region in which the driving coil is wound may be substantially the same as L1c in (a), but the straight length is L3a, which is smaller than L1a by bending the magnetic material in the region in which the driving coil is wound. It may have a length similar to L2a. Therefore, in the magnetic sensor according to an embodiment of the present invention, when the magnetic vector component in the first direction is extracted, the length of the region in which the pickup coil is wound in the first direction is maintained at L3b, and the region in which the driving coil is wound is removed. It can bend inward toward two directions and can reduce the length of the 1st direction of the whole magnetic sensor.

In addition, in (c), the length of the region in which the drive coil providing the alternating current is wound is 2 * L3c, which is substantially similar to 2 * L1c in comparison with the flux gate sensor of FIG. At the same time, the area in which the pick-up coil is wound does not change, and thus it can be seen that the same performance can be maintained when the magnitude of the measured voltage is also Vd3 compared to Vd1.

For example, the voltage sensed by the flux gate sensors of FIG. 7A may have values of Vd1, Vd3 of about 13 Mv, and Vd2 of about 6 Mv in FIG. 7B. Accordingly, the flux gate sensor of FIG. 7A (c) according to an embodiment of the present invention maintains the measured voltage value while reducing its length, thereby improving self-sensing capability.

8 is a diagram illustrating a hall sensor which extracts a vector component in the Z axis direction.

Referring to FIG. 8, the hall sensor 800 measures a magnetic field by measuring a voltage Vs induced by applying a driving current Id to both ends of the hall sensor thin film. For example, when the magnetic field B is applied in the vertical direction of the hall sensor 800, the flow of electrons is bent by a magnetic field applied from the outside, thereby forming a hall voltage.

Hall voltage can be expressed as follows.

[Equation 2]

Vs is the measured Hall voltage, K2 is a constant, Id is the drive current provided to the Hall sensor 800, and B is the magnitude of the magnetic field applied to the Hall sensor 800.

The Hall sensor has a favorable condition for miniaturization than a two-dimensional magnetic sensor because it can be manufactured in a thin film, but is easily affected by an external magnetic field, especially when the Hall sensor is mounted inside an integrated circuit, Due to the generated magnetic field, the value of the hole voltage is easily changed, so it is difficult to expect reliability.

9 is a diagram illustrating an electronic compass according to an embodiment of the present invention.

Referring to FIG. 9, the electronic compass 900a may include a substrate 910, a first direction magnetic sensor 920, a second direction magnetic sensor 930, and a plurality of third direction magnetic sensors 940 and 950. It may include.

The substrate 910 may be a substrate substantially the same as the substrates 610a, 610b, 610c, and 610d described with reference to FIGS. 6A through 6D. The first direction magnetic sensor 920, the second direction magnetic sensor 930, and the plurality of third direction magnetic sensors 940 and 950 may be formed on the substrate 910. A method of forming the respective sensors on the substrate 910 will be described later with reference to FIG. 13.

The first direction magnetic sensor 920 may include a first magnetic body 926 having a 'c' shape including an area extending in the first direction and an area extending in the second direction. In the region extending in the first direction, the first pickup coil 921 is wound to extract the first direction vector component, and in the region extending in the second direction, an alternating current is provided to magnetize the first magnetic body 926. The first drive coils 922 and 923 are wound. However, since the AC current provided by the first driving coils 922 and 923 should be provided in the first direction, the first auxiliary coils 924 and 925 for inducing the direction of the AC current are the first driving coil 922. , 923 and the first pickup coil 921.

The length of the region extending in the first direction of the first magnetic body 926 may be longer than the length of the region extending in the second direction. In FIG. 9, the first magnetic body 926 is illustrated in a form in which both ends are bent vertically in the second direction. However, when both ends are bent in the same direction, the first magnetic body 926 has an angle of 45 ° to 90 °. It is possible to have, but is not limited to the form shown in FIG.

The second direction magnetic sensor 930 may include a second magnetic body 936 having an area extending in the second direction and an area extending in the first direction. The second direction magnetic sensor 930 may include a second pick-up coil 931 surrounding the area extending in the second direction of the second magnetic body 936 and an agent surrounding the area extending in the first direction of the second magnetic body 936. Second drive coils 932 and 933 and second auxiliary coils 934 and 935 for inducing alternating current in a second direction between the second drive coils 922 and 923 and the second pickup coil 931. can do. The role of each coil is substantially the same as the role in the first directional magnetic sensor 920. In addition, the shape of the second direction magnetic sensor 930 is also not limited to that shown in FIG. 9, similarly to the first direction magnetic sensor 920.

In the electronic compass 900a according to an embodiment of the present invention, the vector components in the X-axis and Y-axis directions should be extracted at the same time. The first direction magnetic sensor 920 and the second direction magnetic sensor 930 are paired. It can be driven by the driving pins (dp1, dp2) of. The pair of drive pins dp1, dp2, the first and second drive coils 922, 923, 932, 933, and the first and second auxiliary coils 924, 925, 934, 935 have one current It can form a path.

Thus, when providing a driving current for the first directional magnetic sensor 920, and providing a driving current for the second directional magnetic sensor 930, two pairs of driving pins are required, but in one embodiment of the invention According to the electronic compass 900a, coordinates in two directions can be extracted through a pair of driving pins, which is suitable for miniaturization.

The first pick-up coil 921 for extracting the magnetic vector component in the first direction senses the voltage through the first pick-up pin pairs sp1 and sp2, and the second pick-up coil 931 uses the second pick-up pin pair ( Voltage can be detected through sp3 and sp4).

Since the plurality of third directional magnetic sensors 940 and 950 may be easily influenced by an external magnetic field, the plurality of third directional magnetic sensors 940 and 950 may be driven without being driven at the same time. The third direction vector component may be extracted. Although not shown, a calculation operation such as compensating the third direction vector components may be performed by a separate coordinate extractor.

Since the first and second magnetic bodies 926 and 936 of the first directional magnetic sensor 920 and the second directional magnetic sensor 930 may include a ferromagnetic material, the first and second directional magnetic sensors 920. , 930 is disposed to surround the third direction magnetic sensors 940, 950 and external electromagnetic waves or external waves flowing from the side surfaces of the third direction magnetic sensors 940, 950 without including a separate electromagnetic shielding means. It can block the magnetic field.

Each three-way magnetic sensor 940, 950 may be connected to a pair of drive pins dp3, dp4, dp5, dp6 providing a drive current and a pair of sense pins sp5, sp6, sp7, sp8 for sensing a Hall voltage. have.

In addition, the electronic compass 900a according to an embodiment of the present invention may further include an electromagnetic shielding means 960 to protect the plurality of third direction magnetic sensors 940 and 950 from an external magnetic field. The electromagnetic shielding means 960 may include a ferromagnetic material and a soft magnetic material, and may be disposed to surround the third directional magnetic sensors 940 and 950 on the substrate 910.

Therefore, the electronic compass 900a according to the embodiment of the present invention can reduce the size while maintaining the current driving capability and the voltage sensing capability by bending a portion in which the driving coil is wound, and through the efficient arrangement of the curved magnetic sensors, the hall sensor Because the electromagnetic shielding of can be performed at the same time, the effect of the size reduction can be further improved.

10 is a diagram illustrating an electronic compass according to an embodiment of the present invention. Referring to FIG. 10, when compared with the electronic compass 900a of FIG. 9, the electronic compass 900b further includes a pair of first directional magnetic sensors and a second directional magnetic sensor.

The plurality of first directional magnetic sensors 920a and 920b may be disposed to face each other while facing the center of the substrate 910, that is, the portion where the third directional magnetic sensors 940 and 950 are formed. The directional magnetic sensors 930a and 930b may likewise be arranged to face each other while facing the center of the substrate 910. Through this arrangement, a plurality of first and second directional magnetic sensors 920a, 920b, 930a, and 930b may surround the entire direction of the third directional magnetic sensors 940 and 950, thereby shielding the electromagnetic. At the same time, a plurality of magnetic vector components can be extracted for each direction, thereby improving the reliability of coordinate measurement without excessively increasing the size of the electronic compass 900b.

That is, the electronic compass 900a of FIG. 9 includes only a plurality of third direction magnetic sensors 940 and 950 to extract a third direction vector component compensated by averaging the vector components extracted from each other, but the electronic compass of FIG. 10. 900b may include a plurality of magnetic sensors extracting vector components in the first direction and the second direction to extract the vector component by taking the average even when extracting the first and second direction vector components to perform a compensation operation. have.

Since the first directional magnetic sensor 920a and the second directional magnetic sensor 930a have substantially the same structure as described with reference to FIG. 9, a detailed description thereof will be omitted.

The first directional magnetic sensor 920b added in the embodiment of FIG. 10 is wound by the driving coils 922b and 923b, the pickup coil 921b, and the auxiliary coils 924b and 925b, and the second directional magnetic sensor 920b. 930b is wound by drive coils 932b and 933b, pickup coil 931b, and auxiliary coils 934b and 935b. An alternating current is simultaneously provided to the first and second directional magnetic sensors 920b and 930b by the pair of driving pins dp7 and dp8, and the first directional magnetic sensor 920b is connected to the fourth pair of pickup pins sp9. The second direction magnetic sensor 930b detects the voltage through the fifth pair of pickup pins sp11 and sp12 through sp10.

The electronic compass 900b according to an embodiment of the present invention may operate in pairs with the first and second directional magnetic sensors. For example, the first and second directional magnetic sensors 920a, 920b, and 930a. , 930b) operate at the same time, the first in the coordinate extraction unit (not shown) that has received all the voltage measured at each pickup pin pair (sp1, sp2, sp3, sp4, sp9, sp10, sp11, sp12) Coordinates may be calculated by extracting a vector component in each direction based on an average value of the extraction voltage along the direction and the extraction voltages along the second direction.

In some embodiments, the first and second directional magnetic sensors 920a and 930a or the first and second directional magnetic sensors 920b and 930b may be selectively operated. In this case, the lifespan of each of the magnetic sensors can be extended, and when one magnetic sensor does not operate normally, the stability of the operation can be enhanced by operating another magnetic sensor. Selective operation of the respective magnetic sensors may be performed by a separate control circuit connected to the electronic compass 900b.

FIG. 11 is a conceptual diagram for describing a method of calculating actual coordinates by a coordinate extracting unit based on vector components of respective directions extracted by the electronic compass 900b of FIG. 10.

Referring to FIG. 11, the coordinates of each direction extracted by the electronic compass 900b are averaged to substantially C ((X1 + X2) / 2, (Y1 + Y2) / 2, (Z1 + Z2) / 2). You can see that the coordinates are extracted. In this case, the reliability can be improved compared to the A (X1, Y1, Z1) and B (X2, Y2, Z2) coordinates measured once.

12 is a diagram illustrating an electronic compass according to an embodiment of the present invention.

The electronic compass 900c of FIG. 12 may include magnetic sensors having shapes similar to those of the first direction magnetic sensor 620d and the second direction magnetic sensor 630d described with reference to FIG. 6D.

The first direction magnetic sensors 920c and 920d and the second direction magnetic sensors 920d and 930d of the electronic compass 900c include an area extending in the first direction and an area extending in the second direction. It may have a child shape. However, the position where the pickup coil and the drive coil are wound differs depending on the direction of the vector component to be extracted in each case.

Similarly as described with reference to FIG. 6D, the first direction magnetic sensor 920c includes a first magnetic body 926c including an area extending in the first direction and an area extending in the second direction, and the first direction. The first pickup coil 921c for measuring the voltage is wound in the extended region, and the first driving coil for supplying the alternating current to the end of the region extending in the second direction and the magnetic material extending in the first direction ( 922c and 923c may be wound. In addition, the first auxiliary coil 924c may be wound in a curved region of the first magnetic material 926c to guide the current provided from the first driving coil 922c in the first direction.

The second direction magnetic sensor 930c includes a second magnetic body 936c including a region extending in the first direction and a region extending in the second direction, and extending in the second direction of the second magnetic body 936c. The second pickup coil 931c may be wound around the region, and the second driving coils 932c and 933c may be wound around ends of the region extending in the first direction and the region extending in the second direction. In addition, the second auxiliary coil 934c is wound around the region where the second magnetic body 936c is bent to guide the driving current in the second direction.

The first driving coils 922c and 923c, the first auxiliary coil 924c, the second driving coils 932c and 933c, and the second auxiliary coil 934c are connected to each other so that the pair of driving pins dp1 and dp2 are connected to each other. By receiving an alternating current from the outside. In addition, the first pick-up coil 921c is connected to the first pick-up pin pairs sp1 and sp2 and the second pick-up coil 932c is connected to the second pick-up pin pairs sp3 and sp4, respectively. Measure the voltage due to magnetization reversal.

In addition, descriptions of the third directional magnetic sensors 940 and 950 and the first and second directional magnetic sensors 920d and 930d facing each other will be omitted.

13A to 13J are views illustrating a method of manufacturing an electronic compass according to an embodiment of the present invention.

In order to form a magnetic thin film in FIG. 13A, a photoresist film is applied to a substrate such as a wafer to form a photoresist film, and in FIG. 13B, the photoresist is exposed along the shape of the magnetic body of the magnetic sensor. The photoresist pattern is removed from the shape of the magnetic material. In FIG. 13B, as shown in FIGS. 9 and 10 to form a magnetic body having a 'c' shape, as in another embodiment of the present invention, both ends of the magnetic body are not bent vertically or 45 ° to 90 °. It may have a 'c' shape or a 'b' shape.

In FIG. 13C, the magnetic substrate is applied to a sputtering apparatus having a permanent magnet embedded therein by exposing the substrate having the form of the magnetic substance. The direction of the magnetic field may be substantially the same as the direction in which the magnetic body extracts the magnetic vector component. That is, when the first direction magnetic sensor is formed, the direction of the magnetic field applied through the permanent magnet may correspond to the first direction. The ferromagnetic thin film is formed while the magnetic field is applied, and the photoresist pattern is removed.

In FIG. 13D, a ferromagnetic thin film is formed on the entire surface of the wafer, and in FIG. 13E, the ferromagnetic thin film is ultrasonically cleaned using an organic solvent.

In the method of manufacturing an electronic compass according to an embodiment of the present invention, since the magnetic sensor has a 'c' shape or a 'b' shape unlike the prior art, when the magnetic sensors of the X and Y axes are simultaneously generated on one substrate, For example, magnetic sensors extracting vector components in different directions may be arranged in parallel. For example, an area in which the driving coil of the first direction magnetic sensor is wound may extend in the second direction, and since the area in which the pickup coil of the second direction magnetic sensor is wound also extends in the second direction, they are simultaneously formed. In this case, the magnetization arrangement may be disturbed to reduce the magnitude of the voltage measured at the pickup coil. Therefore, in the process of forming the first direction magnetic sensor for extracting the vector component in the first direction, and applying a magnetic field in the first direction, and in the process of forming the second direction magnetic sensor for extracting the second direction vector component When the magnetization is applied by applying a magnetic field in two directions, it is possible to prevent the magnetization arrangement from being disturbed.

In FIGS. 13F to 13J, a process similar to that in FIGS. 13A to 13E is performed. That is, when the process for forming the first directional magnetic sensor is performed in FIGS. 13A to 13E, the process for forming the second directional magnetic sensor is performed in FIGS. 13F to 13J.

FIG. 14A is an electronic compass implemented in a package further including an application-specific integrated circuit (ASIC) for driving the electronic compass after two-dimensional magnetic sensors are formed based on the processes shown in FIGS. 13A to 13J. 1400 is a perspective view, and FIG. 14B is a cross-sectional view taken along the BB ′ direction of FIG. 14A.

Referring to FIG. 14A, the electronic compass 1400 may include a printed circuit board 1410, a magnetic sensor die 1420 mounted on the printed circuit board 1410, and a driving integrated circuit 1430 for driving the magnetic sensor die 1420. ) May be included.

The magnetic sensor die 1420 may have a structure substantially the same as the electronic compasses 900a, 900b, and 900c described with reference to FIGS. 9, 10, and 12. The magnetic sensor die 1420 may be mounted on the printed circuit board 1410. In addition, an AC current is provided to the magnetic sensor die 1420 on the magnetic sensor die 1420, and an operation of extracting a vector component and calculating coordinates based on the voltage measured from the magnetic sensor die 1420 is performed. The driving integrated circuit 1430 may be stacked. The driving integrated circuit 1430 may include a controller including the coordinate extractor, a driver for selectively driving magnetic sensors, and a detector configured to sense a measurement current or voltage.

The drive integrated circuit 1430 may be bonded through the wire 1452 from the first pad 1442 of the printed circuit board 1410 through the second pad 1444, and the drive integrated circuit 1430 may be a third pad. An alternating current may be provided through the wire 1451 to the fourth pad 1442 of the magnetic sensor die 1420 through the 1443, and a measurement voltage may be provided.

15 is a block diagram illustrating an embodiment of a drive integrated circuit.

Referring to FIG. 15, the driving integrated circuit 1500 may include a controller 1510, a driver 1520, and a detector 1530.

The driving integrated circuit 1500 may be separately implemented with respect to the first to third directional magnetic sensors.

The controller 1510 provides the driving control signal OCON to generate an AC driving signal for the magnetic sensors, for example, a triangle wave, to the driving unit 1520, and the sensing control signal PCON to the sensing unit 1530. The peak voltage detected by the first to third directional magnetic sensors may be provided to the controller 1510.

The controller 1510 may include a coordinate extractor that calculates coordinates by extracting a vector component for each direction based on the measured voltage provided from the detector 1530.

The driver 1520 may receive a driving voltage to provide a driving signal IN to the first to third directional magnetic sensors based on the driving control signal OCON. For example, the driving unit 520 may be implemented as an oscillator.

The detector 1530 may detect the voltage OUT from the first to third directional magnetic sensors and provide the voltage OUT to the controller 1510.

The electronic compass according to an embodiment of the present invention can maintain the pickup area of the ferromagnetic material while bending the area in which the driving coil is wound, thereby reducing the size of the entire magnetic sensor and maintaining the voltage measuring capability.

In addition, the electronic compass according to an embodiment of the present invention may be wrapped by the first and second magnetic sensors including a soft magnetic thin film capable of preventing the inflow of external magnetic fields or external electromagnetic waves in the side portions of the plurality of Hall sensors. This protects the Hall sensor from the effects of an external magnetic field without installing a separate electromagnetic shielding material.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Will be clear to those who have knowledge of.

900a, 900b, 900c: electronic compass
910: substrate
920a, 920b, 920c, and 920d: first direction magnetic sensor
930a, 930b, 930c, and 930d: second direction magnetic sensor
940, 950: third direction magnetic sensor

Claims (21)

A first magnetic body having a first magnetic body extending in a first direction to extract a first direction magnetic vector component, and both ends of the first magnetic body are 45 ° to inward toward a second direction perpendicular to the first direction; A first direction magnetic sensor having a letter 'c' shape bent at 90 °; And
A second magnetic body having a second magnetic body extending in the second direction to extract a second direction magnetic vector component, and both ends of the second magnetic body are bent toward the first direction at an angle of 45 ° to 90 ° inwardly; An electronic compass comprising a second directional magnetic sensor having a shape. The method according to claim 1,
And a drive coil surrounding the bent end portions of each of the first magnetic material and the second magnetic material and providing an alternating current. The method according to claim 2,
And a pick-up coil surrounding a region in which the first magnetic body extends in the first direction and a region in which the second magnetic body extends in the second direction, and measuring a voltage change based on the alternating current. Electronic compass characterized in that. The method according to claim 3,
In each of the first magnetic body and the second magnetic body, the first magnetic body and the second magnetic body are bent between the driving coil and the pickup coil to induce a direction of a magnetic field generated based on the magnetic body and the driving coil. An electronic compass further comprising an auxiliary coil surrounding the losing portion. The method according to claim 3,
And the first driving coil surrounding the first magnetic body and the second driving coil surrounding the second magnetic body are connected between a pair of driving pins to form a single current path. The method according to claim 3,
The first pickup coil surrounding the first magnetic body forms a current path with a pair of first pickup pins, and the second pickup coil surrounding the second magnetic body forms a current path with a pair of second pickup pins. Electronic compass, characterized in that for performing a pickup operation. The method according to claim 1,
At least one Hall sensor extracting a magnetic vector component in a third direction perpendicular to the first and second directions,
And the hall sensor is formed in the center of the substrate on which the first and second magnetic sensors are formed and is surrounded by the first and second directional magnetic sensors. The method according to claim 7,
And a coordinate extractor configured to extract a compensated third direction vector component based on at least one magnetic vector component of the third direction extracted by each hall sensor. Compass. The method according to claim 8,
And an application-specific integrated circuit (ASIC) including the coordinate extractor and the driving unit for driving the first direction magnetic sensor, the second direction magnetic sensor, and the hall sensor. . The method according to claim 8,
When there are a plurality of first directional magnetic sensors and second directional magnetic sensors, the centers of the substrates are disposed to face each other.
The coordinate extractor may include first and second directional vector components compensated based on the first directional magnetic vector component and the second directional magnetic vector components extracted by the plurality of first and second directional magnetic sensors. Electronic compass characterized in that the extraction. The method according to claim 9,
The plurality of first directional magnetic sensors light second directional magnetic sensors are each driven by separate pins. A first magnetic body formed on the substrate, the first magnetic body including a first pick-up region extending in a first direction and a first driving region extending in a second direction perpendicular to the first direction to obtain a first direction magnetic vector component; A first directional magnetic sensor to extract;
A second magnetic body formed on the substrate and including a second pickup region extending in the second direction and a second driving region extending in the first direction to extract a second direction magnetic vector component; Directional magnetic sensor; And
A hall sensor formed in the center of the substrate and extracting a magnetic vector component in a third direction perpendicular to the first and second directions, wherein the hall sensor is formed by the first and second direction magnetic sensors; And an electronic compass arranged to be enclosed. The method of claim 12,
And first and second drive coils surrounding the first and second drive regions and providing alternating current. The method according to claim 13,
The first driving coil includes a first driving auxiliary coil surrounding one end of the first magnetic material in the first pickup region,
And the second driving coil includes a second driving auxiliary coil surrounding one end of the second magnetic material in the second pickup region. The method according to claim 13,
And first and second pickup coils surrounding the first and second pickup regions and measuring a voltage induced based on the alternating current. The method of claim 12,
A first crossing region where the first driving region and the first pickup region meet each other in the first magnetic body and a second crossing region where the second driving region and the second pickup region meet each other in the second magnetic body And first and second auxiliary coils for assisting a voltage induction operation by the first driving coil and the second driving coil. delete A method of manufacturing an electronic compass comprising: a first directional magnetic sensor extracting a vector component in a first direction; and a second directional magnetic sensor extracting a vector component in a second direction perpendicular to the first direction.
Applying a magnetic field in the second direction to form a first ferromagnetic material included in the first direction magnetic sensor; And
Applying a magnetic field in the first direction to form a second ferromagnetic material included in the second direction magnetic sensor,
The first ferromagnetic material extends in the first direction, and both ends of the first directional magnetic sensor are 'c' shaped bent inwardly toward the second direction. A method of manufacturing an electronic compass comprising: a first directional magnetic sensor extracting a vector component in a first direction; and a second directional magnetic sensor extracting a vector component in a second direction perpendicular to the first direction.
Applying a magnetic field in the second direction to form a first ferromagnetic material included in the first direction magnetic sensor; And
Applying a magnetic field in the first direction to form a second ferromagnetic material included in the second direction magnetic sensor,
The second ferromagnetic material extends in the second direction, and both ends of the second direction magnetic sensor are 'c' shaped bent inwardly toward the first direction. The method according to any one of claims 18 and 19,
Forming the first ferromagnetic material,
Forming a photoresist pattern having a form of the first ferromagnetic material on a wafer;
Forming a first ferromagnetic thin film on the photoresist pattern while applying a magnetic field in the first direction; And
And removing the photoresist pattern. The method according to any one of claims 18 and 19,
Forming the second ferromagnetic material,
Forming a photoresist pattern having a form of the second ferromagnetic material on a wafer;
Forming a first ferromagnetic thin film on the photoresist pattern while applying a magnetic field in the second direction; And
And removing the photoresist pattern.

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