A magnetic field sensor and a method for detecting magnetic field components based on the magnetic field sensor

Abstract

The present application discloses a magnetic field sensor and a method for detecting magnetic field components based on the magnetic field sensor, the magnetic field sensor includes a first magnetic focusing part, at least two magnetic induction parts and at least two second magnetic focusing parts, at least two magnetic induction parts are arranged at both ends of one side surface of the first magnetic focusing part; at least two second magnetic focusing parts are arranged on a side surface of the matching corresponding magnetic induction part away from the first magnetic focusing part; the orthographic projection of the second magnetic focusing part on the corresponding magnetic induction part at least partially overlaps with the orthographic projection of the first magnetic focusing part on the corresponding magnetic induction part, and the overlapping area is at least partially located in the sensitive area of ​​the corresponding magnetic induction part. The magnetic field sensor in the present application has high sensitivity and high isolation, has differential anti-interference capability, can simultaneously detect magnetic field components in two axes (X-axis and Z-axis), and suppress the magnetic field of the third axis, and the magnetic field sensor is thin, small in size, and simple in structure.

Description

Technical Field

[0001] The present application relates to the field of magnetic sensing Hall devices, and in particular to a magnetic field sensor and a method for detecting magnetic field components based on the magnetic field sensor. Background Art

[0002] Hall sensors are widely used as switches or linear sensors, playing an irreplaceable role in proximity triggering, motor commutation, current sensing, position sensing and other scenarios. However, the Hall device itself can only be sensitive to the magnetic field in the Z-axis direction of the chip surface, and cannot detect the magnetic field in the X-axis direction. Applications such as those that require multi-dimensional magnetic field detection and weak correlation between intensity and direction are greatly limited.

[0003] Although the current 2D Hall magnetic field sensors can meet the above-mentioned needs, they also face problems such as complex processes, high costs, and large sizes. At the same time, Hall devices may encounter magnetic field interference problems caused by ambient magnetic fields or stray currents during application. Summary of the invention

[0004] In order to overcome the above shortcomings, the purpose of the present application is to provide a magnetic field sensor and a method for detecting magnetic field components based on the magnetic field sensor. The magnetic field sensor is small in size and simple in structure. It can simultaneously detect the magnetic field components of two axes (X-axis and Z-axis) and suppress the magnetic field of the third axis (Y-axis).

[0005] In order to achieve the above objectives, this application adopts the following technical solutions:

[0006] A magnetic field sensor, comprising:

[0007] A first magnetic focusing part;

[0008] At least two magnetic induction parts are arranged at two ends of one side surface of the first magnetic focusing part, and the two magnetic induction parts are located in the same plane;

[0009] At least two second magnetic focusing parts are arranged on a side surface of the magnetic induction part away from the first magnetic focusing part;

[0010] The orthographic projection of the second magnetic focusing portion on the corresponding magnetic induction portion at least partially overlaps with the orthographic projection of the first magnetic focusing portion on the corresponding magnetic induction portion, and the overlapping area is at least partially located in the sensitive area of ​​the corresponding magnetic induction portion.

[0011] In one embodiment, the second magnetic concentrating portion and the corresponding magnetic induction portion are staggered and biased toward a side away from the adjacent magnetic induction portion.

[0012] In one embodiment, one end of the second magnetic concentrating portion close to the adjacent magnetic sensing portion passes through a sensitive central area of ​​the corresponding magnetic sensing portion.

[0013] In one embodiment, both ends of the first magnetic focusing portion in the X-axis direction respectively pass through the sensitive central area of ​​the corresponding magnetic induction portion, and both ends of the first magnetic focusing portion in the X-axis direction do not exceed one end of the corresponding magnetic induction portion away from the adjacent magnetic induction portion.

[0014] In one embodiment, the magnetic induction parts are symmetrically arranged with a first midline between the two magnetic induction parts as an axis;

[0015] The two second magnetic concentrating parts are axially symmetrically distributed about the first midline;

[0016] The second center line of the first magnetic focusing portion coincides with the first center line, and a cross-sectional shape of the first magnetic focusing portion in the X-axis direction is an axisymmetric shape.

[0017] In one embodiment, the area of ​​the overlapping region within the sensitive area is greater than one fifth of the area of ​​the sensitive area corresponding to the magnetic sensing portion.

[0018] In one embodiment, the thickness of each magnetic sensing portion in the Z-axis direction is between 50 and 5000 nanometers;

[0019] Or the thickness of each magnetic sensing portion in the Z-axis direction is between 0.1 mm and 1 mm;

[0020] The thickness of the first magnetic focusing portion and the second magnetic focusing portion in the Z-axis direction are both between 30 and 300 microns.

[0021] In one embodiment, the two magnetic sensing parts are arranged close to each other or spaced apart.

[0022] In one embodiment, each of the magnetic sensing parts is provided with a pin, and the pin is electrically connected to an electrode of the magnetic sensing part;

[0023] The pins are used to lead out the electrodes of the magnetic sensing unit and apply voltage and / or detect voltage signals to the electrodes.

[0024] The embodiment of the present application also provides a method for detecting magnetic field components based on the above-mentioned magnetic field sensor, the method comprising:

[0025] Based on a predetermined Z-axis magnetic field, determining the Z-axis voltage signals output by the two magnetic sensing parts, and obtaining the Z-axis sensitivity coefficients of the two magnetic sensing parts;

[0026] Based on a predetermined X-axis magnetic field, determining the X-axis voltage signal output by the two magnetic sensing units, and obtaining the X-axis sensitivity coefficients of the two magnetic sensing units;

[0027] The current Z-axis magnetic field component and the X-axis magnetic field component are determined according to the Z-axis sensitivity coefficients of the two magnetic sensing units, the X-axis sensitivity coefficients of the two magnetic sensing units, and the voltage signals currently output by the two magnetic sensing units. Beneficial Effects

[0028] The present application generates directional bidirectional magnetic deflection by respectively arranging the first magnetic focusing part and the second magnetic focusing part on the two opposite sensing surfaces of the magnetic sensing part, so that the X-axis magnetic field is respectively introduced into the two magnetic sensing parts in two opposite directions to generate differential signals, thereby realizing the magnetic field detection of two axes (X-axis and Z-axis), and being insensitive to the magnetism of the Y-axis. At the same time, by respectively arranging the second magnetic focusing part on the upper sensing surfaces of the two magnetic sensing parts, and the first magnetic focusing part simultaneously contacting the lower sensing surfaces of the two magnetic sensing parts, the sensitivity of the X-axis magnetic field detection can be increased to 5-8 times of the original single-sided placement of the magnetic focusing part, and the sensitivity of the Z-axis magnetic field detection can be increased to 3-6 times of the original single-sided placement of the magnetic focusing part. In addition, the requirements for the installation positions of the first magnetic focusing part, the second magnetic focusing part and the magnetic sensing part are not high, and the installation positions of the first magnetic focusing part and the second magnetic focusing part are insensitive. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings are used to provide an understanding of the technical solution of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the technical solution of the present disclosure and do not constitute a limitation on the technical solution of the present disclosure. The shapes and sizes of the components in the accompanying drawings do not reflect the actual proportions and are only intended to illustrate the content of the present application.

[0030] Figure 1 A schematic diagram of the magnetic field sensor in the Z-axis direction provided in an embodiment of the present application.

[0031] Figure 2 Schematic diagram of the direction of magnetic lines of force in the magnetic field of an embodiment of the present application.

[0032] Figure 3 This is a schematic diagram of the second magnetic focusing portion in the X-axis direction provided in an embodiment of the present application.

[0033] Figure 4 This is a schematic diagram of the first magnetic focusing portion in the X-axis direction provided in an embodiment of the present application.

[0034] Figure 5 This is a schematic diagram of the magnetic field sensor in the Z-axis direction when two magnetic sensing parts of an embodiment of the present application are arranged side by side.

[0035] Figure 6 A schematic diagram of the magnetic field sensor in the Z-axis direction when the magnetic sensing part provided in the embodiment of the present application is a Hall bare chip.

[0036] Figure 7 A schematic diagram of the second magnetic focusing part in the X-axis direction when the magnetic sensing part provided in the embodiment of the present application is a Hall bare chip. DETAILED DESCRIPTION

[0037] The above scheme is further described below in conjunction with specific examples. It should be understood that these examples are used to illustrate the present application and are not limited to the scope of the present application. The implementation conditions adopted in the examples can be further adjusted as the conditions of the specific manufacturer, and the unspecified implementation conditions are usually the conditions in conventional experiments.

[0038] Unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present disclosure should be understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connecting" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. In this article, "electrical connection" includes the situation where the constituent elements are connected together through an element with some electrical function. "Elements with some electrical function" are not particularly limited as long as they can transfer electrical signals between the connected constituent elements. "Elements with some electrical function" can be, for example, electrodes or wiring, or switching elements such as transistors, or other functional elements such as resistors, inductors or capacitors. "Up", "down", "left", "right", etc. are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0039] In this application, the directions or positional relationships indicated by the terms "upper", "lower", "inner", "middle", etc. are based on the directions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific direction, or to be constructed and operated in a specific direction.

[0040] The present application discloses a magnetic field sensor and a method for detecting magnetic field components based on the magnetic field sensor. The magnetic field sensor includes a first magnetic focusing portion, at least two magnetic induction portions and at least two second magnetic focusing portions. The at least two magnetic induction portions are respectively arranged at two ends of a side surface of the first magnetic focusing portion, and the two magnetic induction portions are located in the same plane; at least two second magnetic focusing portions are respectively arranged on a side surface of the two magnetic induction portions away from the first magnetic focusing portion; the orthographic projection of the second magnetic focusing portion on the corresponding magnetic induction portion at least partially overlaps with the orthographic projection of the first magnetic focusing portion on the corresponding magnetic induction portion, and the overlapping area is at least partially located in the sensitive area of ​​the corresponding magnetic induction portion. The magnetic field sensor in the present application has high sensitivity and high isolation, and has differential anti-interference capability. It can simultaneously detect magnetic field components of two axes (X-axis and Z-axis) and suppress the magnetic field of the third axis. The magnetic field sensor is thin in thickness, small in size and simple in structure.

[0041] Next, combine Figure 1-Figure 7 The magnetic field sensor provided by the embodiment of the present application is described below. The magnetic field sensor has high integration, high sensitivity and high anti-interference ability, and is small in size and simple in structure.

[0042] The magnetic field sensor comprises a packaging sleeve (not shown in the drawings), a first magnetic concentrator 10, at least two magnetic sensing parts 20, at least two second magnetic concentrators 30 and a data processing unit (not shown in the drawings).

[0043] The packaging sleeve hermetically packages the first magnetic concentrator 10, the at least two magnetic induction parts 20 and the at least two second magnetic concentrators 30 as a whole, and specifically, the first magnetic concentrator 10, the at least two magnetic induction parts 20 and the at least two second magnetic concentrators 30 are hermetically packaged based on an injection molding process;

[0044] At least two magnetic induction parts 20 are arranged at two ends of one side surface of the first magnetic focusing part 10, and the two magnetic induction parts 20 are located in the same plane;

[0045] At least two second magnetic focusing parts 30 are arranged on one side surface of the two magnetic induction parts 20 away from the first magnetic focusing part 10;

[0046] The orthographic projection of the second magnetic focusing portion 30 on the corresponding magnetic induction portion 20 at least partially overlaps with the orthographic projection of the first magnetic focusing portion 10 on the corresponding magnetic induction portion 20, and the overlapping area is at least partially located in the sensitive area of ​​the corresponding magnetic induction portion 20;

[0047] The data processing unit is electrically connected to both magnetic sensing units 20 , and is used to obtain the X-axis magnetic field component and the Z-axis magnetic field component according to the voltage signal output by each magnetic sensing unit 20 and the sensitivity coefficient of each magnetic sensing unit 20 .

[0048] It should be noted that the present application generates a directional bidirectional magnetic conduction deflection by respectively arranging the first magnetic focusing part and the second magnetic focusing part on two opposite sensing surfaces of the magnetic sensing part, so that the X-axis magnetic field is respectively introduced into the two magnetic sensing parts along two opposite directions to generate a differential signal, thereby realizing the magnetic field detection of two axes (X-axis and Z-axis). At the same time, by respectively configuring the second magnetic focusing part on the upper sensing surfaces of the two magnetic sensing parts, and the first magnetic focusing part simultaneously contacting the lower sensing surfaces of the two magnetic sensing parts, the detection sensitivity of the X-axis magnetic field and the Z-axis magnetic field can be improved, and it does not have high requirements on the installation positions of the first magnetic focusing part, the second magnetic focusing part and the magnetic sensing part, and is not sensitive to the installation positions of the first magnetic focusing part and the second magnetic focusing part.

[0049] refer to Figure 2 In a specific embodiment, the two magnetic induction parts 20 are respectively a first magnetic induction part 20a and a second magnetic induction part 20b, and the first magnetic induction part 20a and the second magnetic induction part 20b are respectively arranged at two ends of one side surface of the first magnetic focusing part 10, and the two second magnetic focusing parts 30 include a second left magnetic focusing part 30a and a second right magnetic focusing part 30b. The second left magnetic focusing part 30a is arranged on a side surface of the first magnetic induction part 20a away from the first magnetic focusing part 10, and the second right magnetic focusing part 30b is arranged on a side surface of the second magnetic induction part 20b away from the first magnetic focusing part 10. The projection of the first magnetic focusing part 10 on the first magnetic induction part 20a and the projection of the second left magnetic focusing part 30a on the first magnetic induction part 20a at least partially overlap, and at least a part of the overlapping area is located in the sensitive area of ​​the first magnetic induction part 20a. The projection of the magnetic part 10 on the second magnetic sensing part 20b at least partially overlaps with the projection of the second right magnetic focusing part 30b on the second magnetic sensing part 20b, and at least a part of the overlapping area is located in the sensitive area of ​​the second magnetic induction. The second left magnetic focusing part 30a converts the direction of the magnetic lines of force N of the X-axis magnetic field into the Z-axis direction. Under the joint action of the first magnetic focusing part 10 and the second left magnetic focusing part 30a, the magnetic lines of force N of the X-axis magnetic field enter the first magnetic sensing part 20a in the first direction. The first magnetic focusing part 10 will conduct the magnetic lines of force N passing through the first magnetic sensing part 20a to the second magnetic sensing part 20b, and then, in cooperation with the second right magnetic focusing part 30b, introduce them into the second magnetic sensing part 20b in the second direction, wherein the first direction and the second direction are parallel to each other but in opposite directions, and thus the detection of the magnetic field components of the two axes can be achieved by differential detection.

[0050] In this embodiment, the area of ​​the overlapping region located in the sensitive zone is greater than 0.2 times the area of ​​the sensitive zone of the corresponding magnetic sensing unit. This design allows more X-axis magnetic fields to be introduced into the sensitive zone of the magnetic sensing unit, thereby enhancing the sensitivity of X-axis and Z-axis magnetic field detection, thereby improving the detection accuracy of the magnetic field sensor.

[0051] refer to Figure 1-Figure 3, in this embodiment, the second magnetic focusing part 30 is arranged in a dislocation manner with respect to its corresponding magnetic induction part 20, and is biased towards the side away from the adjacent magnetic induction part 20. Further, one end 32 of the second magnetic focusing part 30 close to the adjacent magnetic induction part 20 passes through the sensitive central area S of the corresponding magnetic induction part. It should be noted that in this embodiment, the sensitive central area S is a region that diffuses around the central axis M, and this region is the most sensitive place for magnetic field detection. Such a design is beneficial to improving the edge effect of the second magnetic focusing part 30, converting more X-axis magnetic fields into Z-axis magnetic fields. At the same time, passing one end 32 of the second magnetic focusing part 30 close to the adjacent magnetic induction part 20 through the sensitive central area s of the corresponding magnetic induction part allows more Z-axis magnetic fields to be introduced into the sensitive area of the magnetic induction part, which is beneficial to improving the detection accuracy of the magnetic field sensor. In a specific embodiment, the length by which one end of the second magnetic focusing part 30 away from the adjacent magnetic induction part 20 exceeds the corresponding magnetic induction part 20 is L, and the length of each magnetic induction part 20 at the relative two ends in the X-axis direction is a. Among them, 0.2a < L < a. When the length L is within this numerical range, more X-axis magnetic fields can be introduced into the corresponding magnetic induction part 20.

[0052] Reference Figure 1 and Figure 4 , in this embodiment, the two ends of the first magnetic focusing part 10 in the X-axis direction respectively pass through the sensitive central area S of the corresponding magnetic induction part, and the two ends of the first magnetic focusing part 10 in the X-axis direction do not exceed the end 22 of the corresponding magnetic induction part away from the adjacent magnetic induction part. Such a design avoids the X-axis magnetic field being directly conducted by the first magnetic focusing part and not being detected by the magnetic induction part, improving the detection accuracy of the magnetic field sensor. In a specific embodiment, the length of the first magnetic focusing part 10 in the X-axis direction is K, and the length of the two magnetic induction parts 20 in the X-axis direction is W. Among them, W - 0.2a ≤ k ≤ W. The width e of the first magnetic focusing part 10 in the Y-axis direction is not less than 0.3 times the side length a of the magnetic induction part 20 and not greater than twice the side length a of the magnetic induction part 20, 0.3a ≤ e ≤ 2a. That is, when the length K and width e of the first magnetic focusing part 10 are within the above numerical ranges, the magnetic conduction effect of the first magnetic focusing part 10 can be better exerted, so as to introduce the X-axis magnetic field passing through one magnetic induction part into the other magnetic induction part. And through the cooperation with the second magnetic focusing part 30, the X-axis magnetic fields introduced into the two magnetic induction parts are in opposite directions, thus forming a magnetic field differential signal.

[0053] Reference Figure 2 and Figure 3, the positional relationship among the first magnetic focusing part 10, the magnetic sensing part 20 and the second magnetic focusing part 30 is specifically described below with the first magnetic sensing part 20a, the second left magnetic focusing part 30a and the first magnetic focusing part 10, the second left magnetic focusing part 30a includes a first end 31a and a second end 32a arranged opposite to each other along the X-axis direction, the first magnetic sensing part 20a includes a third end 21a and a fourth end 22a arranged opposite to each other along the X-axis direction, the first magnetic focusing part includes a fifth end 11a and a sixth end 12a arranged opposite to each other along the X-axis direction, wherein the first end 31a is closer to the second right magnetic focusing part 30b than the second end 32a, the second left magnetic focusing part 30 The first end 31a of a passes through the sensitive central area S of the first magnetic sensing part 20a, and the first end 31a does not exceed the third end 21a of the first magnetic sensing part, the second end 32a of the second left magnetic focusing part 30a exceeds the fourth end 22a of the first magnetic sensing part 20a, and the sixth end 12a of the first magnetic focusing part 10 passes through the sensitive central area S of the first magnetic sensing part 20a and does not exceed the fourth end 22a of the first magnetic sensing part 20a. The magnetic field sensor designed in this way can increase the X-axis magnetic field detection sensitivity to 5-8 times of the original single-sided magnetic focusing part, and increase the Z-axis magnetic field detection sensitivity to 3-6 times of the original single-sided magnetic focusing part.

[0054] refer to Figure 1-Figure 4 In this embodiment, the two magnetic sensing parts 20 are symmetrically arranged with the first center line H between the two magnetic sensing parts 20 as the axis, and the two second magnetic focusing parts are symmetrically distributed with the first center line H; the cross-section of the second magnetic focusing part 30 in the X-axis direction is circular, elliptical or polygonal, and the thickness d2 of the first magnetic focusing part and the second magnetic focusing part in the Z-axis direction is between 30-300 microns (μm). Furthermore, the second center line of the first magnetic focusing part 10 coincides with the first center line H, and the cross-sectional figure of the first magnetic focusing part 10 in the X-axis direction is an axisymmetric figure. This design makes the entire magnetic field sensor symmetrically arranged about the first center line H, thereby making the magnetic field sensor insensitive to the Y-axis magnetic field. If the Y-axis magnetic field appears, the magnetic field sensor has no signal response, thereby achieving the suppression of the Y-axis magnetic field.

[0055] refer to Figure 1 and Figure 5 In this embodiment, the two magnetic sensing parts 20 are arranged close to each other or spaced apart. Specifically, when the packaging space of the magnetic field sensor is relatively sufficient, the two magnetic sensing parts 20 are spaced apart from each other (such as Figure 1 As shown in FIG. 1 ), when the packaging space in the sensor device is small, the two magnetic sensing parts 20 are arranged close to each other (as shown in FIG. 1 ). Figure 5 As shown), the two magnetic induction parts 20 are connected by curing with glue.

[0056] In a specific embodiment, the materials of the first magnetic focusing part 10 and the second magnetic focusing part 30 are both non-magnetic. The first magnetic focusing part 10 can be made of ferrite, nanomagnetic crystals or other materials with high magnetic permeability, and the second magnetic focusing part 30 can be made of ferrite, nanomagnetic crystals or other materials with high magnetic permeability. The materials of the first magnetic focusing part 10 and the second magnetic focusing part can be the same or different. Preferably, the materials of the first magnetic focusing part 10 and the second magnetic focusing part 30 are the same.

[0057] refer to Figure 3 and Figure 5-Figure 7 In a specific embodiment, each magnetic sensing unit is provided with a pin, which is electrically connected to the electrode of the magnetic sensing unit; in this embodiment, the electrode of the magnetic sensing unit includes a working electrode 25 and a signal electrode 26, and the pin is used to lead out the working electrode 25 and the signal electrode 26 of the magnetic sensing unit, and apply a working voltage to the working electrode 25, and / or to sense the voltage signal output by the signal electrode 26.

[0058] refer to Figure 5-Figure 7 In a specific embodiment, the two magnetic sensing parts 20 can be selected as Hall bare chips or Hall elements. When the two magnetic sensing parts are selected as Hall bare chips, the thickness of the two magnetic sensing parts (i.e., the Hall bare chips) in the Z-axis direction is between 50-5000 nanometers (nm). When the two magnetic sensing parts are selected as Hall elements, the thickness of the two magnetic sensing parts (i.e., the Hall elements) in the Z-axis direction is between 0.1-1 millimeters (mm).

[0059] refer to Figure 5 When both magnetic sensing parts are Hall elements 20c, the two Hall elements 20c with pins 27c are directly glued and bonded to the first magnetic focusing part 10. If the two Hall elements 20c are arranged close together, the two Hall elements 20c are first glued and bonded together with glue, and then the second magnetic focusing part 30 is glued and bonded to the sensing surface of each Hall element 20c on the side away from the first magnetic focusing part 10. Finally, based on the injection molding process, the above-mentioned Hall elements 20c, the first magnetic focusing part 10 and the second magnetic focusing part 30 are packaged to form a magnetic field sensor, wherein the pins 27c of the two Hall elements 20c are exposed in the packaged magnetic field sensor, and the two exposed pins 27c are the pins of the entire magnetic field sensor.

[0060] refer to Figure 6-Figure 7When both magnetic sensing parts are Hall bare chips 20d, a lead frame 40 is arranged between the Hall bare chip 20d and the first magnetic focusing part 10. In the actual installation process, two Hall bare chips 20d are firstly bonded to the surface of one side of the lead frame 40, and the electrodes (metal pad electrodes) of each Hall bare chip 20d are respectively connected to the pins 27d of the lead frame 40, and then the second magnetic focusing part 30 is bonded to the sensing surface of each Hall bare chip 20d away from the lead frame 40, and then the first magnetic focusing part 10 is bonded to the surface of the side of the lead frame 40 away from the Hall bare chip 20d, and finally the above-mentioned Hall bare chip 20d, the first magnetic focusing part 10 and the second magnetic focusing part 30 are packaged based on the injection molding process. In this embodiment, the lead frame 40 can be set to any suitable shape and made of suitable materials such as copper, aluminum and their alloy materials.

[0061] refer to Figure 5-Figure 7 In this embodiment, the thickness d1 of each magnetic induction portion in the Z-axis direction is between 50-5000 nanometers; or the thickness d1' of each magnetic induction portion in the Z-axis direction is between 0.1-1 millimeters. Specifically, Figure 5 As shown, when the two magnetic sensing parts use Hall elements, the thickness d1 of the two magnetic sensing parts (ie, Hall elements) in the Z-axis direction is between 0.1 and 1 mm. Figure 6 As shown, when the two magnetic sensing parts use Hall bare chips, the thickness d1' of the two magnetic sensing parts (i.e., the Hall bare chips) in the Z-axis direction is between 50 and 5000 nanometers (nm). The thickness within this numerical range can enhance the magnetic conductivity effect between the first magnetic focusing part 10 and the second magnetic focusing part 30, and guide the magnetic lines of force of the X-axis magnetic field to pass through one of the second magnetic focusing parts 30 and the corresponding magnetic sensing part 20 to better enter the first magnetic focusing part 10, thereby improving the detection sensitivity of the magnetic field sensor. Furthermore, since the Hall element is in a packaged state, the thickness in the Z-axis direction is thicker than that of the Hall bare chip. In order to guide the magnetic lines of force of the X-axis magnetic field to pass through one of the second magnetic focusing parts 30 and the corresponding magnetic sensing part 20 to better enter the first magnetic focusing part 10, the thickness of the Hall element in the Z-axis direction does not exceed 1 millimeter (mm), wherein the magnetic sensing part is preferably a Hall bare chip. At this time, the thickness of the magnetic sensing part in the Z-axis direction is smaller, which is more conducive to enhancing the magnetic conductivity effect between the first magnetic focusing part 10 and the second magnetic focusing part 30, thereby improving the detection sensitivity of the magnetic field sensor.

[0062] The embodiment of the present application also provides a method for detecting magnetic field components based on the above magnetic field sensor, the detection method comprising:

[0063] Based on a predetermined Z-axis magnetic field, determining the Z-axis voltage signals output by the two magnetic sensing parts, and obtaining the Z-axis sensitivity coefficients of the two magnetic sensing parts;

[0064] Based on a predetermined X-axis magnetic field, determining the X-axis voltage signal output by the two magnetic sensing units, and obtaining the X-axis sensitivity coefficients of the two magnetic sensing units;

[0065] The current Z-axis magnetic field component and the X-axis magnetic field component are determined according to the Z-axis sensitivity coefficients of the two magnetic sensing units, the X-axis sensitivity coefficients of the two magnetic sensing units, and the voltage signals currently output by the two magnetic sensing units.

[0066] The specific detection method of the magnetic field components of the X-axis and Z-axis is:

[0067] Given a Z-axis magnetic field, the first magnetic sensing unit and the second magnetic sensing unit respectively output a first Z-axis voltage signal and a second Z-axis voltage signal; data processing is performed based on the given Z-axis magnetic field, the first Z-axis voltage signal and the second Z-axis voltage signal to obtain a sensitivity coefficient a1 of the Z-axis magnetic field of the first magnetic sensing unit and a sensitivity coefficient a2 of the Z-axis magnetic field of the second magnetic sensing unit.

[0068] Given an X-axis magnetic field, the first magnetic sensing unit and the second magnetic sensing unit respectively output a first X-axis voltage signal and a second X-axis voltage signal; data processing is performed based on the given X-axis magnetic field, the first X-axis voltage signal and the second X-axis voltage signal to respectively obtain a sensitivity coefficient b1 of the X-axis magnetic field of the first magnetic sensing unit and a sensitivity coefficient b2 of the X-axis magnetic field of the second magnetic sensing unit;

[0069] The data processing unit obtains the current X-axis magnetic field component and the Z-axis magnetic field component based on the sensitivity coefficient a1 of the Z-axis magnetic field of the first magnetic sensing unit, the sensitivity coefficient a2 of the Z-axis magnetic field of the second magnetic sensing unit, the sensitivity coefficient b1 of the X-axis magnetic field of the first magnetic sensing unit, the sensitivity coefficient b2 of the X-axis magnetic field of the second magnetic sensing unit, and the current voltage signals respectively output by the first magnetic sensing unit and the second magnetic sensing unit.

[0070] The specific calculation process is as follows:

[0071] In an ideal state, that is, when the first magnetic focusing part, the two second magnetic focusing parts and the two magnetic induction parts are symmetrical about the first midline, a1 and a2 are equal, and b1 and b2 are equal; after applying working voltages to the working electrodes of the first magnetic induction part and the second magnetic induction part respectively, when the Z-axis magnetic field B1 passes through, the first magnetic induction part and the second magnetic induction part output the same Z-axis voltage signal. When the X-axis magnetic field B2 passes through, the magnetic field deflection generated by the first magnetic focusing part and the second magnetic focusing part makes the X-axis voltage signal sensed by the first magnetic induction part opposite to the X-axis voltage signal sensed by the second magnetic induction part, forming a difference;

[0072] When the Z-axis magnetic field B1 is given, the signal electrodes of the first magnetic sensing unit and the second magnetic sensing unit respectively output the first Z-axis voltage signal V A1 and the second Z-axis voltage signal V B1 , where VA1 =V B1 = a1B1;

[0073] When the X-axis magnetic field B2 is given, the signal electrodes of the first magnetic sensing unit and the second magnetic sensing unit respectively output the first X-axis voltage signal V A2 and the second X-axis voltage signal V B2 , where V A2 = -b1B2, V B2 = b1B2;

[0074] The sensitivity coefficient of the Z-axis magnetic field of the first magnetic sensing unit and the second magnetic sensing unit is a1 = V A1 / B1, the sensitivity coefficient of the X-axis magnetic field of the first magnetic sensing unit and the second magnetic sensing unit b1 = V B2 / B2;

[0075] When actually measuring, the signal electrodes of the first magnetic induction unit and the second magnetic induction unit respectively output the current voltage signal which is the external Z-axis magnetic field component B z and the X-axis magnetic field component B x The superposition of

[0076] Therefore, the voltage signal V output by the first magnetic induction unit is a =a1B z -b1B x , the voltage signal V output by the second magnetic induction unit b =a1B z +b1B x , we can calculate B x =(V b -V a ) / 2b1,B z =(V b +V a ) / 2a1.

[0077] On the other hand, in the actual installation process, it is difficult to ensure that the first magnetic focusing part, the two second magnetic focusing parts and the two magnetic induction parts are completely symmetrical. If there is an installation error, a1 and a2 are not equal, b1 and b2 are not equal. After applying working voltages to the working electrodes of the first magnetic induction part and the second magnetic induction part respectively, when the Z-axis magnetic field B1 passes through, the first magnetic induction part and the second magnetic induction part respectively output Z-axis voltage signals; when the X-axis magnetic field B2 passes through, the magnetic field deflection generated by the first magnetic focusing part and the second magnetic focusing part causes the X-axis voltage signal sensed by the first magnetic induction part and the X-axis voltage signal output by the second magnetic induction part to be opposite, forming a difference;

[0078] When the Z-axis magnetic field B1 is given, the signal electrodes of the first magnetic sensing unit and the second magnetic sensing unit respectively output the first Z-axis voltage signal V A1 and the second Z-axis voltage signal VB1 , where V A1 = a1B1; V B1 = a2B1;

[0079] When the X-axis magnetic field B2 is given, the first magnetic focusing part and the second magnetic focusing part converge and then introduce the first magnetic induction part and the second magnetic induction part, and the signal electrodes of the first magnetic induction part and the second magnetic induction part respectively output the first X-axis voltage signal V A2 and the second X-axis voltage signal V B2 , where V A2 = -b1B2, V B2 = b2B2;

[0080] Specifically, by giving the Z-axis magnetic field B1 and the X-axis magnetic field B2, and the first Z-axis voltage signal V A1 , the second Z-axis voltage signal V B1 , the first X-axis voltage signal V A2 and the second X-axis voltage signal V B2 , the sensitivity coefficient of the Z-axis magnetic field of the first magnetic sensing unit can be obtained as a1= V A1 / B1; sensitivity coefficient of the Z-axis magnetic field of the second magnetic sensing unit a2 = V B1 / B1; The sensitivity coefficient of the X-axis magnetic field of the first magnetic sensing unit b1 = -V A2 / B2; The sensitivity coefficient of the X-axis magnetic field of the second magnetic sensing unit b2 = V B2 / B2;

[0081] When actually measuring, the signal electrodes of the first magnetic induction unit and the second magnetic induction unit respectively output the current voltage signal which is the external Z-axis magnetic field component B z and the X-axis magnetic field component B x The superposition of

[0082] Therefore, the voltage signal V output by the first magnetic induction unit is a =a1B z -b1B x , the voltage signal V output by the second magnetic sensing unit b =a2B z + b2B x , we get B x =(a1V b - a2V a ) / (a1b2+a2b1), B z =(b1V b +b2V a ) / (a1b2+a2b1), that is, the X-axis magnetic field component and the Z-axis magnetic field component are obtained.

[0083] The above embodiments are only for illustrating the technical concept and features of the present application, and their purpose is to enable people familiar with the technology to understand the content of the present application and implement it accordingly, and they cannot be used to limit the protection scope of the present application. Any equivalent transformation or modification made according to the spirit of the present application shall be included in the protection scope of the present application.

Claims

1. A magnetic field sensor, characterized in that: include: A first magnetic focusing part; Two magnetic sensing parts are arranged at two ends of one side surface of the first magnetic focusing part, and the two magnetic sensing parts are both selected as Hall bare chips or Hall elements; Two second magnetic focusing parts are arranged on a side surface of the matching corresponding magnetic induction part away from the first magnetic focusing part, the second magnetic focusing part and the corresponding magnetic induction part are staggered and biased to the side away from the adjacent magnetic induction part, both ends of the first magnetic focusing part in the X-axis direction do not exceed the end of the corresponding magnetic induction part away from the adjacent magnetic induction part, and the end of the second magnetic focusing part close to the adjacent magnetic induction part passes through the sensitive central area of ​​the corresponding magnetic induction part; The orthographic projection of the second magnetic focusing portion on the corresponding magnetic induction portion at least partially overlaps with the orthographic projection of the first magnetic focusing portion on the corresponding magnetic induction portion, and the overlapping area is at least partially located in the sensitive area of ​​the corresponding magnetic induction portion.

2. The magnetic field sensor according to claim 1, characterized in that: Two ends of the first magnetic concentrating portion in the X-axis direction respectively pass through the sensitive central area of ​​the magnetic induction portion corresponding thereto.

3. The magnetic field sensor according to claim 1, characterized in that: The magnetic induction parts are symmetrically arranged with the first midline between the two magnetic induction parts as the axis; The two second magnetic concentrating parts are axially symmetrically distributed with the first midline as the axis; The second center line of the first magnetic focusing portion coincides with the first center line, and a cross-sectional shape of the first magnetic focusing portion in the X-axis direction is an axisymmetric shape.

4. The magnetic field sensor according to claim 1, characterized in that: The area of ​​the overlapping region within the sensitive area is greater than one fifth of the area of ​​the sensitive area corresponding to the magnetic sensing portion.

5. The magnetic field sensor according to claim 1, characterized in that: When both of the two magnetic sensing parts are selected as the Hall bare chip; the thickness of each magnetic sensing part in the Z-axis direction is between 50-5000 nanometers; When both of the two magnetic sensing parts are selected as the Hall element, the thickness of each magnetic sensing part in the Z-axis direction is between 0.1 mm and 1 mm; The thickness of the first magnetic focusing portion and the second magnetic focusing portion in the Z-axis direction are both between 30 and 300 microns.

6. The magnetic field sensor according to claim 1, characterized in that: The two magnetic induction parts are arranged close to each other or spaced apart.

7. The magnetic field sensor according to claim 1, characterized in that: Each of the magnetic induction parts is provided with a pin, and the pin is electrically connected to the electrode of the magnetic induction part; The pins are used to lead out the electrodes of the magnetic sensing unit and apply voltage and / or detect voltage signals to the electrodes.

8. A method for detecting magnetic field components based on the magnetic field sensor according to any one of claims 1 to 7, characterized in that: include: Based on a predetermined Z-axis magnetic field, determining the Z-axis voltage signals output by the two magnetic sensing parts, and obtaining the Z-axis sensitivity coefficients of the two magnetic sensing parts; Based on a predetermined X-axis magnetic field, determining the X-axis voltage signal output by the two magnetic sensing units, and obtaining the X-axis sensitivity coefficients of the two magnetic sensing units; The current Z-axis magnetic field component and the X-axis magnetic field component are determined according to the Z-axis sensitivity coefficients of the two magnetic sensing units, the X-axis sensitivity coefficients of the two magnetic sensing units, and the voltage signals currently output by the two magnetic sensing units.

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