WO2022067994A1

WO2022067994A1 - Rotation angle detection method and system

Info

Publication number: WO2022067994A1
Application number: PCT/CN2020/128557
Authority: WO
Inventors: 姜杰
Original assignee: 重庆睿歌微电子有限公司
Priority date: 2020-09-29
Filing date: 2020-11-13
Publication date: 2022-04-07
Also published as: CN112361954A

Abstract

A rotation angle detection method and system, the angle detection method comprising: an AMR anisotropic magnetoresistor (1) performs initial rotation angle detection; a first vertical Hall sensor (2) senses a component of a magnetic field in a first direction; a second vertical Hall sensor (3) senses a component of the magnetic field in a second direction, the second direction being perpendicular to the first direction; and a corresponding rotation angle is detected in combination with output results of the AMR anisotropic magnetoresistor (1), the first vertical Hall sensor (2) and the second vertical Hall sensor (3). The rotation angle detection method and system may not only make full use of the AMR anisotropic magnetoresistor (1) to achieve high resolution accuracy, but also makes full use of the first vertical Hall sensor (2) and the second vertical Hall sensor (3) to determine the angle interval in which same is located so as to achieve 0 to 360° high-resolution accuracy angle detection.

Description

Rotation angle detection method and system

technical field

The invention belongs to the technical field of integrated circuits, and relates to an angle measurement method, in particular to a rotation angle detection method and system.

Background technique

Anisotropic magnetoresistance (AMR) refers to the phenomenon that the resistivity of ferromagnetic materials changes with the change of its own magnetization and the angle between the current direction; its microscopic mechanism is based on the density of states and spin correlation induced by spin-orbit coupling. Anisotropy of scattering; this is different from other magnetoresistive effects (eg GMR, TMR, etc.) that rely on spin electron injection and detection.

Based on the above properties of AMR anisotropic magnetoresistance, AMR anisotropic magnetoresistance is used to detect the change in rotation angle. However, since the anisotropic magnetoresistance of AMR has the same induction to the north and south poles of the magnetic field, it can only achieve a detection range of 0 to 180° in applications used for angle detection, and cannot satisfy most of the full range of 0 to 360°. The need for range angle detection.

In view of this, there is an urgent need to design a new angle detection method in order to overcome at least some of the above-mentioned shortcomings of the existing angle detection methods.

SUMMARY OF THE INVENTION

The invention provides a rotation angle detection method and system, which can make full use of AMR anisotropic magnetoresistance to achieve high resolution accuracy, and can make full use of vertical Hall to determine the angle range in which it is located, so as to achieve 0-360° high-resolution precision angle detection.

In order to solve the above-mentioned technical problems, according to one aspect of the present invention, the following technical solutions are adopted:

A rotation angle detection method, the angle detection method comprises:

AMR anisotropic magnetoresistor for initial rotation angle detection;

The first vertical Hall sensor induces the component of the magnetic field in the first direction (the direction is parallel to the surface of the device);

The second vertical Hall sensor senses the component of the magnetic field in the second direction (the direction is parallel to the surface of the device); the second direction is perpendicular to the first direction (and both are parallel to the surface of the device);

Combined with the output results of the AMR anisotropic magnetoresistor, the first vertical Hall sensor and the second vertical Hall sensor, the corresponding rotation angle is obtained by detection.

As an embodiment of the present invention, the acquisition angle of the AMR anisotropic magnetoresistor is n° or (n+180)°; wherein, 0≤n<180;

According to the output results of the first vertical Hall sensor and the second vertical Hall sensor, the rotation angle is determined at [0°～90°), [90°～180°), [180°～270°), 270°～ 360°) one of four intervals;

According to the interval determined by the angle, determine whether the angle is n° or (n+180)°; if the rotation angle is determined in the [0°～90°) interval or [90°～180°) interval, the angle is n°; if If the rotation angle is determined in the [180°～270°) interval or 270°～360°) interval, the angle is (n+180)°.

As an embodiment of the present invention, the first direction is the X axis, and the second direction is the Y axis.

As an embodiment of the present invention, the 0° position of the X-axis of the first vertical Hall sensor coincides with the 0° position of the AMR magnetoresistive bridge, then:

The first vertical Hall sensor is turned over, and the second vertical Hall sensor is turned over, the rotation angle detected by the AMR anisotropic magnetoresistor is [0°～90°);

If the first vertical Hall sensor is not flipped, and the second vertical Hall sensor is flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [90°～180°);

If the first vertical Hall sensor is not flipped, and the second vertical Hall sensor is not flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [180°～270°);

If the first vertical Hall sensor is flipped and the second vertical Hall sensor is not flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [270°˜360°).

According to another aspect of the present invention, the following technical solution is adopted: a rotation angle detection system, the rotation angle detection system includes:

AMR anisotropic magnetoresistor for initial rotation angle detection;

a first Hall sensor for sensing the component of the magnetic field in a first direction (the direction is parallel to the surface of the device);

The second Hall sensor is used to sense the component of the magnetic field in the second direction (the direction is parallel to the surface of the device); the second direction is perpendicular to the first direction (and both are parallel to the surface of the device);

The angle detection unit is used for detecting the corresponding rotation angle in combination with the output results of the AMR anisotropic magnetoresistor, the first vertical Hall sensor and the second vertical Hall sensor.

The angle detection unit is used to determine whether the angle is n° or (n+180)° according to the interval determined by the angle; if the rotation angle is determined to be in the [0°～90°) interval or [90°～180°) interval, The angle is n°; if the rotation angle is determined in the [180°～270°) interval or the 270°～360°) interval, the angle is (n+180)°.

As an embodiment of the present invention, the first vertical Hall sensor and the second vertical Hall sensor are vertically arranged.

As an embodiment of the present invention, the first vertical Hall sensor and the second vertical Hall sensor are arranged parallel to the surface of the setting device.

As an embodiment of the present invention, the first direction is the X axis, and the second direction is the Y axis;

The 0° position of the X-axis of the first vertical Hall sensor coincides with the 0° position of the AMR magnetoresistive bridge, then:

As an embodiment of the present invention, the AMR anisotropic magnetoresistor, the first vertical Hall sensor and the second vertical Hall sensor are arranged in a chip.

The beneficial effects of the present invention are: the rotation angle detection method and system proposed by the present invention can not only make full use of the AMR anisotropic magnetoresistance to achieve high resolution accuracy, but also make full use of the vertical Hall to determine the angle range in which it is located, To achieve high-resolution angle detection of 0 to 360°.

Description of drawings

FIG. 1 is a schematic diagram of the composition of a rotation angle detection system according to an embodiment of the present invention.

FIG. 2 is a flowchart of a rotation angle detection method according to an embodiment of the present invention.

FIG. 3-1 is a schematic diagram of the use of a rotation angle detection system in an embodiment of the present invention.

3-2 is a schematic diagram of the use of a rotation angle detection system in an embodiment of the present invention.

FIG. 4 is a schematic diagram of the principle of angle detection by AMR anisotropic magnetoresistance in an embodiment of the present invention.

5 is a schematic diagram of a two-axis vertical Hall, an AMR anisotropic magnetoresistance, and a magnet in an embodiment of the present invention.

FIG. 6 is a schematic diagram of an angle interval in which a two-axis vertical Hall-assisted AMR is implemented to determine an embodiment of the present invention.

FIG. 7 is a schematic diagram of a two-axis vertical Hall-assisted AMR implementing 0-360° detection according to an embodiment of the present invention.

Detailed ways

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

In order to further understand the present invention, the preferred embodiments of the present invention are described below with reference to the examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the claims of the present invention.

The description in this section is only for a few typical embodiments, and the present invention is not limited to the scope of the description of the embodiments. It is also within the scope of the description and protection of the present invention to replace some technical features in the embodiments with the same or similar prior art means.

The present invention discloses a rotation angle detection system. FIG. 1 is a schematic diagram of the composition of the rotation angle detection system in an embodiment of the present invention; please refer to FIG. 1 , the rotation angle detection system includes: an AMR anisotropic magnetoresistor 1; A vertical Hall sensor 2, a second vertical Hall sensor 3 and an angle detection unit 4 (wherein the first vertical Hall sensor 2 and the second vertical Hall sensor 3 form a two-axis vertical Hall sensor 20, as shown in FIG. 6 . Show). The AMR anisotropic magnetoresistor 1 is used to detect the initial rotation angle; the first vertical Hall sensor 2 is used to sense the component of the magnetic field in the first direction; the second vertical Hall sensor 3 is used to sense the magnetic field in the second direction. component; the first direction is parallel to the surface of the device, the second direction is parallel to the surface of the device, and the second direction is perpendicular to the first direction. The angle detection unit 4 is used for combining the output results of the AMR anisotropic magnetoresistor 1 , the first vertical Hall sensor 2 and the second vertical Hall sensor 3 to detect the corresponding rotation angle.

In an embodiment of the present invention, the acquisition angle of the AMR anisotropic magnetoresistor is n° or (n+180)°, wherein 0≦n<180. According to the output results of the first vertical Hall sensor and the second vertical Hall sensor, the rotation angle is determined at [0°～90°), [90°～180°), [180°～270°), 270°～ 360°) in one of four zones. The angle detection unit is used to determine whether the angle is n° or (n+180)° according to the interval determined by the angle; if the rotation angle is determined to be in the [0°～90°) interval or [90°～180°) interval, The angle is n°; if the rotation angle is determined in the [180°～270°) interval or the 270°～360°) interval, the angle is (n+180)°.

In an embodiment of the present invention, the first vertical Hall sensor (also referred to as the X-axis vertical Hall) 2 and the second vertical Hall sensor (also referred to as the Y-axis vertical Hall) 3 are vertically arranged (Can be combined with Figure 6). In one embodiment, the first vertical Hall sensor 2 and the second vertical Hall sensor 3 are arranged parallel to the surface of the setting device. In an embodiment of the present invention, the first direction is the X axis, and the second direction is the Y axis.

Assuming that the 0° of the vertical Hall X-axis coincides with the 0° position of the AMR magnetoresistive bridge under a certain placement relationship, please refer to Table 1.

AMR磁阻计算得到的角度θThe angle θ calculated by the AMR magnetoresistance	第一霍尔传感器first hall sensor	第二霍尔传感器second hall sensor
在0～90°区间in the range of 0 to 90°	翻转flip	翻转flip
在90～180°区间In the range of 90 to 180°	未翻转not flipped	翻转flip
在180～270°区间In the range of 180～270°	未翻转not flipped	未翻转not flipped
在270～360°区间In the range of 270～360°	翻转flip	未翻转not flipped

Table 1 The relationship between the angle and the first Hall sensor and the second Hall sensor

As can be seen from Table 1, if the first vertical Hall sensor is flipped and the second vertical Hall sensor is flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [0°～90°); the If the first vertical Hall sensor is not flipped, and the second vertical Hall sensor is flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [90°～180°); the first vertical Hall sensor is not flipped , and the second vertical Hall sensor is not flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [180°～270°); the first vertical Hall sensor is flipped, and the second vertical Hall sensor If it is not flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [270°～360°).

In an embodiment of the present invention, the AMR anisotropic magnetoresistor, the first vertical Hall sensor and the second vertical Hall sensor may be arranged in a chip. Of course, the combination of AMR and vertical Hall can be various, including: integrating vertical Hall and AMR in one chip; integrating vertical Hall and signal processing circuit in one chip; integrating vertical Hall and AMR in one chip; The AMR is packaged in one package; the vertical Hall device and the AMR device are placed in close proximity and other forms. The two-axis vertical Hall sensor and the AMR anisotropic magnetoresistor 1 can also be arranged in various ways, such as the arrangement in Figure 3-1, Figure 3-2, and Figure 5.

The principle of AMR anisotropic magnetoresistance to achieve angle detection is shown in Figure 4. Generally, it consists of two pairs of AMR magnetoresistance bridges arranged at 45°. With the rotation of the external magnetic field parallel to the surface of the AMR magnetoresistance bridge , the bridge outputs the voltage signals of Sin (2θ) and Cos (2θ) that change with the rotation angle θ, and the value of θ can be obtained by calculation (such as calculation through a dedicated ASIC circuit or MCU). It can be seen from Figure 4 that the output of the AMR anisotropic magnetoresistance bridge is exactly the same in the range of 0 to 180° and the range of 180° to 360°. Therefore, when the AMR anisotropic magnetoresistance is used for angle detection, the actual Only angular intervals up to 180° can be resolved.

Fig. 5 discloses the detection schematic diagram of the rotation angle detection method of the present invention when the magnets are placed on the shaft end and the side. Please refer to Fig. 5, the magnet 30 can be rotated by the rotating shaft 31; the vertical Hall device and the AMR anisotropic magnetoresistive device It can be arranged on one side of the magnet 30 , or can be arranged on one end of the magnet 30 . Vertical Hall devices, like AMR anisotropic magnetoresistive devices, can sense magnetic field changes parallel to the device surface. Therefore, the use of two vertical Halls (in the XY plane parallel to the surface of the device) at 90° to each other can assist the AMR anisotropic magnetoresistive bridge to achieve angle detection from 0 to 360°. As shown in Figure 5, the magnet It can be placed on the Z axis or on the side. Note: Both the anisotropic magnetoresistive AMR and the vertical Hall VHS here sense magnetic field components parallel to the XY plane.

The X-axis vertical Hall senses the component on the X axis of the magnetic field parallel to the device surface (XY plane in Figure 5); the Y axis vertical Hall senses the component on the Y axis of the magnetic field parallel to the device surface (XY plane in Figure 5); As shown in FIG. 6 , the two-axis vertical Hall sensor 20 is in the range of 0 to 360°, and can assist in determining four ranges of 0° to 90°, 90° to 180°, 180° to 270°, and 270° to 360° .

The present invention further discloses a rotation angle detection method. FIG. 2 is a flowchart of the rotation angle detection method in an embodiment of the present invention; please refer to FIG. 2 , the angle detection method includes:

Step S1, the AMR anisotropic magnetoresistor performs initial rotation angle detection;

Step S2, the first vertical Hall sensor induces the component of the magnetic field in the first direction; the first direction is parallel to the surface of the device;

Step S3, the second vertical Hall sensor induces the component of the magnetic field in the second direction; the second direction is parallel to the surface of the device, and the second direction is perpendicular to the first direction;

Step S4 , combining the output results of the AMR anisotropic magnetoresistor, the first vertical Hall sensor, and the second vertical Hall sensor to detect the corresponding rotation angle, see FIG. 7 .

In one embodiment, the first direction is the X-axis, and the second direction is the Y-axis.

In an embodiment of the present invention, the acquisition angle of the AMR anisotropic magnetoresistor is n° or (n+180)°; wherein, 0≤n<180; through the first vertical Hall sensor and the second vertical According to the output result of the Hall sensor, the rotation angle is determined in one of four ranges of [0°～90°), [90°～180°), [180°～270°), and 270°～360°). According to the interval determined by the angle, determine whether the angle is n° or (n+180)°; if the rotation angle is determined in the [0°～90°) interval or [90°～180°) interval, the angle is n°; if If the rotation angle is determined in the [180°～270°) interval or 270°～360°) interval, the angle is (n+180)°.

In an embodiment of the present invention, it is assumed that the 0° position of the X-axis of the vertical Hall and the 0° position of the AMR magnetoresistive bridge are coincident in a certain arrangement relationship, please refer to Table 1: the first vertical Hall If the sensor is flipped, and the second vertical Hall sensor is flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [0°～90°); the first vertical Hall sensor is not flipped, and the second vertical Hall sensor is not flipped. If the Hall sensor is flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [90°～180°); the first vertical Hall sensor is not flipped, and the second vertical Hall sensor is not flipped, then the AMR The rotation angle detected by the anisotropic magnetoresistor is [180°～270°); the first vertical Hall sensor is flipped, and the second vertical Hall sensor is not flipped, then the AMR anisotropic magnetoresistor detects the rotation angle. The rotation angle is [270°～360°).

To sum up, the rotation angle detection method and system proposed by the present invention can not only make full use of the AMR anisotropic magnetoresistance to achieve high resolution accuracy, but also make full use of the vertical Hall to determine the angle range in which it is located, so as to achieve high resolution. Angle detection with high resolution accuracy from 0 to 360°.

The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity, all possible combinations of the technical features in the above-described embodiments are not described. However, as long as there is no contradiction between the combinations of these technical features, All should be regarded as the scope described in this specification.

The description and application of the present invention herein is illustrative, and is not intended to limit the scope of the present invention to the above-described embodiments. The effects or advantages involved in the embodiments may be interfered by various factors and may not be embodied in the embodiments, and the description of the effects or advantages is not intended to limit the embodiments. Variations and variations of the embodiments disclosed herein are possible, and alternative and equivalent various components of the embodiments are known to those of ordinary skill in the art. It should be apparent to those skilled in the art that the present invention may be implemented in other forms, structures, arrangements, proportions, and with other components, materials and components without departing from the spirit or essential characteristics of the invention. Other modifications and changes of the embodiments disclosed herein may be made without departing from the scope and spirit of the invention.

Claims

A rotation angle detection method, characterized in that the angle detection method comprises:

AMR anisotropic magnetoresistor for initial rotation angle detection;

The first vertical Hall sensor induces a component of the magnetic field in a first direction; the first direction is parallel to the surface of the device;

The second vertical Hall sensor senses the component of the magnetic field in the second direction; the second direction is parallel to the surface of the device, and the second direction is perpendicular to the first direction;

Combining with the output results of the AMR anisotropic magnetoresistor, the first Hall sensor and the second Hall sensor, the corresponding rotation angle is obtained by detection.
Rotation angle detection method according to claim 1, is characterized in that:

The acquisition angle of the AMR anisotropic magnetoresistor is n° or (n+180)°; wherein, 0≤n<180;

According to the output results of the first vertical Hall sensor and the second vertical Hall sensor, the rotation angle is determined at [0°～90°), [90°～180°), [180°～270°), 270°～ 360°) one of four intervals;

According to the interval determined by the angle, determine whether the angle is n° or (n+180)°; if the rotation angle is determined in the [0°～90°) interval or [90°～180°) interval, the angle is n°; if If the rotation angle is determined in the [180°～270°) interval or 270°～360°) interval, the angle is (n+180)°.
Rotation angle detection method according to claim 1, is characterized in that:

The first direction is the X axis, and the second direction is the Y axis.
Rotation angle detection method according to claim 1, is characterized in that:

The 0° position of the X-axis of the first vertical Hall sensor coincides with the 0° position of the AMR magnetoresistive bridge, then:

The first vertical Hall sensor is turned over, and the second vertical Hall sensor is turned over, the rotation angle detected by the AMR anisotropic magnetoresistor is [0°～90°);

If the first vertical Hall sensor is not flipped, and the second vertical Hall sensor is flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [90°～180°);

If the first vertical Hall sensor is not flipped, and the second vertical Hall sensor is not flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [180°～270°);

If the first vertical Hall sensor is flipped and the second vertical Hall sensor is not flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [270°˜360°).
A rotation angle detection system, characterized in that the rotation angle detection system comprises:

AMR anisotropic magnetoresistor for initial rotation angle detection;

a first vertical Hall sensor for sensing the component of the magnetic field in a first direction, the first direction being parallel to the surface of the device;

a second vertical Hall sensor for sensing the component of the magnetic field in a second direction, the second direction being parallel to the surface of the device; the second direction being perpendicular to the first direction;

The angle detection unit is used for detecting the corresponding rotation angle in combination with the output results of the AMR anisotropic magnetoresistor, the first vertical Hall sensor and the second vertical Hall sensor.
The angle detection system according to claim 5, wherein:

The acquisition angle of the AMR anisotropic magnetoresistor is n° or (n+180)°; wherein, 0≤n<180;

According to the output results of the first vertical Hall sensor and the second vertical Hall sensor, the rotation angle is determined at [0°～90°), [90°～180°), [180°～270°), 270°～ 360°) one of four intervals;

The angle detection unit is used to determine whether the angle is n° or (n+180)° according to the interval determined by the angle; if the rotation angle is determined to be in the [0°～90°) interval or [90°～180°) interval, The angle is n°; if the rotation angle is determined in the [180°～270°) interval or the 270°～360°) interval, the angle is (n+180)°.
The angle detection system according to claim 5, wherein:

The first vertical Hall sensor and the second vertical Hall sensor are vertically arranged.
The angle detection system according to claim 5, wherein:

The first vertical Hall sensor and the second vertical Hall sensor are arranged parallel to the surface of the setting device.
The angle detection system according to claim 5, wherein:

The first direction is the X axis, and the second direction is the Y axis;

The 0° position of the X-axis of the first vertical Hall sensor coincides with the 0° position of the AMR magnetoresistive bridge, then:

The first vertical Hall sensor is turned over, and the second vertical Hall sensor is turned over, the rotation angle detected by the AMR anisotropic magnetoresistor is [0°～90°);

If the first vertical Hall sensor is not flipped, and the second vertical Hall sensor is flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [90°～180°);

The first vertical Hall sensor is not turned over, and the second vertical Hall sensor is not turned over, then the rotation angle detected by the AMR anisotropic magnetoresistor is [180°～270°);

If the first vertical Hall sensor is flipped and the second vertical Hall sensor is not flipped, the rotation angle detected by the AMR anisotropic magnetoresistor is [270°˜360°).
The angle detection system according to claim 5, wherein:

The AMR anisotropic magnetoresistor, the first vertical Hall sensor and the second vertical Hall sensor are arranged in a chip.