TWI638140B - Magnetic field sensing apparatus - Google Patents

Abstract

A magnetic field sensing device includes a plurality of first magnetoresistance units with a magnetic field sensing axis parallel to the first direction, a plurality of second magnetoresistive units with a magnetic field sensing axis parallel to the second direction, and a third direction for measuring Magnetic sensing component of the magnetic field component. The first and second magnetoresistive units are disposed adjacent to the magnetic sensing element and electrically connected to the at least one Wheatstone full bridge at two different times to respectively measure the magnetic field components of the fourth direction and the fifth direction, And causing the Wheatstone full bridge to output two signals corresponding to the magnetic field components of the fourth direction and the fifth direction, respectively, the first direction, the second direction, the third direction, the fourth direction, and the fifth direction are different from each other, The fourth direction is a sum vector direction of the first direction and the second direction, and the fifth direction is a difference vector direction of the first direction and the second direction.

Description

Magnetic field sensing device

The invention relates to a magnetic field sensing device, and in particular to a magnetic field sensing device capable of detecting a three-dimensional magnetic field.

With the popularity of portable electronic devices, the technology of an electronic compass capable of sensing the geomagnetic direction has received attention. When an electronic compass is applied to a small portable electronic device (such as a smart phone), in addition to the small volume requirement, the electronic compass is preferably capable of achieving three-axis sensing because the user When holding the phone in your hand, it may be held obliquely, and various holding angles may also occur. In addition, the electronic compass can also be applied to drones (such as remote control aircraft, remote control helicopters, etc.), and the electronic compass is also preferably capable of achieving three-axis sensing.

In the prior art, an anisotropic magneto-resistive resistor (AMR resistor) is commonly used and a sensing operation of a magnetic field is performed through a Wheatstone bridge architecture, but a magnetic field of a conventional technique is used. Sensing devices often require a large layout area, resulting in an increase in production costs.

Embodiments of the present invention provide a magnetic field sensing device including a plurality of first magnetoresistive units, a plurality of second magnetoresistive units, and a magnetic sensing element. The magnetic field sensing axes of the first magnetoresistive units are parallel to the first direction, and the magnetic field sensing axes of the second magnetoresistive units are parallel to the second direction. The magnetic sensing component is configured to measure a magnetic field component in a third direction, wherein the first magnetoresistive unit and the second magnetoresistive unit are disposed adjacent to the magnetic sensing component, wherein the first magnetoresistive unit and the second magnetic component The resistance unit is electrically connected to the at least one Wheatstone full bridge at two different times to respectively measure the magnetic field components in the fourth direction and the fifth direction, and the at least one Wheatstone full bridge output corresponds to the fourth Two directions of the magnetic field component of the direction and the fifth direction, the first direction, the second direction, the third direction, the fourth direction, and the fifth direction are different from each other, and the fourth direction is a sum vector direction of the first direction and the second direction The fifth direction is a difference vector direction of the first direction and the second direction.

In an embodiment of the invention, the signal output by the at least one Wheatstone bridge is a magnetic field component corresponding to one of the fourth direction and the fifth direction at any of the two different times. The differential signal, at this time, the difference signal of the magnetic field component corresponding to the other of the fourth direction and the fifth direction generated by the at least one Wheatstone bridge is zero.

In an embodiment of the invention, the first magnetoresistive units and the second magnetoresistive units are respectively disposed on adjacent sides of the magnetic sensing element.

In an embodiment of the invention, the magnetic field sensing device further includes a plurality of magnetization direction setting components respectively disposed adjacent to the first magnetoresistive unit and the second magnetoresistive unit to respectively set the first magnetoresistance The magnetization direction of the unit and these second magnetoresistive units.

In an embodiment of the invention, the magnetic field sensing device further includes a substrate, wherein the magnetic sensing elements, the first magnetoresistive units, the second magnetoresistive units, and the magnetization direction setting elements are disposed on a surface of the substrate And the area of the first magnetoresistive unit, the second magnetoresistive unit and the magnetization direction setting elements covering the surface and the area of the magnetic sensing element covering the surface are separated from each other.

In an embodiment of the invention, the at least one Wheatstone bridge is a fixed connection of a Wheatstone full bridge, and the magnetization direction setting components respectively respectively apply the first magnetics at two different times. The magnetization directions of the resistance unit and the second magnetoresistance units are set to two different combinations, so that the Wheatstone full bridge measures the magnetic field components in the fourth direction and the fifth direction at two different times, respectively Two signals corresponding to the magnetic field components of the fourth direction and the fifth direction are output.

In an embodiment of the invention, each of the first magnetoresistive units includes a plurality of first magnetoresistors, and some of the first magnetoresistors have opposite magnetization directions and the other portions, respectively. Each of the two magnetoresistive units includes a plurality of second magnetoresistors, one of the second magnetoresistors having an opposite magnetization direction from the other portion.

In an embodiment of the invention, the magnetization directions of one of the first magnetoresistors and the other portion are set to face each other, and the magnetization direction of one of the second magnetoresistors and the other portion is set to Point to each other.

In an embodiment of the invention, the magnetization directions of one of the first magnetoresistors and the other portion are set to point to each other, and the magnetization directions of one of the second magnetoresistors and the other portion are set to be mutually Point to each other.

In an embodiment of the invention, the first magnetoresistors and the second magnetoresistors are anisotropic magnetoresistors having an extending direction, and the surfaces of the first magnetoresistors and the second magnetoresistors are respectively opposite to each other A plurality of shorting bars extending obliquely in the extending direction, wherein the inclination directions of the shorting bars on the surface of the partial magnetoresistance in which the first magnetoresistance and the second magnetoresistance are the same are opposite to each other.

In an embodiment of the invention, the magnetic field sensing device further includes a switching circuit electrically connecting the first magnetoresistive unit and the second magnetoresistive unit, wherein at least one of the Wheatstone bridges is two kinds of benefits. Stern full bridge, the switching circuit electrically connects these first magnetoresistance units and these second magnetoresistance units into two kinds of Wheatstone bridges at two different times, and the two types of Wheatstone bridges are respectively measured. The magnetic field components of the four directions and the fifth direction respectively output two signals corresponding to the magnetic field components of the fourth direction and the fifth direction.

In an embodiment of the invention, each of the first magnetoresistive units and the second magnetoresistive units includes at least one anisotropic magnetoresistance.

In an embodiment of the invention, the extending direction of the anisotropic magnetoresistance in the first magnetoresistive unit is parallel to the second direction and belongs to the extending direction of the anisotropic magnetoresistance in the second magnetoresistive unit. Parallel to the first direction.

In an embodiment of the invention, the magnetic field sensing device further includes a substrate, wherein the magnetic sensing elements, the first magnetoresistive units and the second magnetoresistive units are disposed on a surface of the substrate, and the first direction The second direction is parallel to the surface, and the third direction is perpendicular to the surface.

In an embodiment of the invention, the substrate is a semiconductor substrate, a glass substrate, or a circuit substrate.

In an embodiment of the invention, the first direction, the second direction, and the third direction are perpendicular to each other, and the fourth direction is perpendicular to the fifth direction, and the fourth direction is sandwiched between the first direction and the second direction. degree.

Based on the above, the magnetic field sensing device of the embodiment of the present invention uses a plurality of first magnetoresistive units whose magnetic field sensing axis is parallel to the first direction, a plurality of second magnetoresistive units whose magnetic field sensing axis is parallel to the second direction, and Magnetic sensing component. The magnetic sensing component is configured to measure a magnetic field component in a third direction, and the first and second magnetoresistive elements are disposed adjacent to the magnetic sensing component and electrically connected to at least one Wheatstone full bridge at two different times , respectively, measuring the magnetic field components of the fourth direction and the fifth direction, and causing the Wheatstone full bridge output two signals corresponding to the magnetic field components of the fourth direction and the fifth direction, respectively, wherein the first direction, the first The two directions, the third direction, the fourth direction, and the fifth direction are different from each other, the fourth direction is a sum vector direction of the first direction and the second direction, and the fifth direction is a difference vector direction of the first direction and the second direction. Therefore, the magnetic field sensing device of the embodiment of the present invention can have a simplified structure and at the same time can realize three-dimensional magnetic field measurement, and thus can have a small volume, thereby achieving an advantage of increasing flexibility in application and reducing manufacturing cost.

The above described features and advantages of the invention will be apparent from the following description.

1A and 1B are schematic diagrams showing a magnetic field sensing device according to an embodiment of the present invention. 1A is a top view of a magnetic field sensing device according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view of the magnetic field sensing device of FIG. 1A taken along line A-A. Referring to FIG. 1A and FIG. 1B , the magnetic field sensing device 100 of the present embodiment includes a plurality of first magnetoresistive units 110 , a plurality of second magnetoresistive units 120 , a plurality of magnetization direction setting elements 130 , and a magnetic sensing element 210 . .

In the embodiment, the first magnetoresistive units 110, the second magnetoresistive units 120, the magnetization direction setting elements 130 and the magnetic sensing elements 210 are disposed on the surface S of the substrate 150, wherein the first magnetoresistive unit 110 The magnetic field sensing axis is parallel to the first direction D1, and can induce a magnetic field component in the first direction D1. The magnetic field sensing axis of the second magnetoresistive unit 120 is parallel to the second direction D2, and can be induced in the second direction D2. Magnetic field component. The first magnetoresistive unit 110 and the second magnetoresistive unit 120 are respectively disposed beside the magnetic sensing component 210. As illustrated in FIG. 1A, the first magnetoresistive unit 110 and the second magnetoresistive unit 120 are respectively disposed on the magnetic sensing component. Adjacent two sides 212, 214 of 210.

The magnetization direction setting elements 130 are disposed beside the first magnetoresistive unit 110 and the second magnetoresistive unit 120, respectively, to set the magnetization directions of the first magnetoresistive unit 110 and the second magnetoresistive unit 120, respectively. The magnetization direction setting component 130 may be selectively disposed adjacent to, above, below, or at a position of the first magnetoresistive unit 110 or the second magnetoresistive unit 120, which is not limited in the present invention.

In other embodiments, the magnetization direction setting component 130 may also be selected not to be disposed on the surface S of the substrate 150. In the substrate 150, those skilled in the art may appropriately change according to actual needs and designs. This is not limited. The substrate 150 is, for example, a semiconductor substrate (such as a germanium substrate), a glass substrate or a circuit substrate, wherein the circuit substrate is, for example, a germanium substrate provided with a conductive line and having a surface covered with an insulating layer, which is not limited in the present invention, and has general knowledge in the art. The person can make appropriate choices according to the prior art.

The magnetic sensing element 210 is a magnetic field component for measuring the third direction D3, and the third direction D3 is, for example, the direction of the vertical surface S. In this embodiment, the first direction D1 and the second direction D2 are parallel to the direction of the surface S, and the first direction D1, the second direction D2 and the third direction D3 are perpendicular to each other, as shown in FIG. 1A and FIG. 1B. Right angle coordinate system.

In the present embodiment, the magnetic sensing element 210 is, for example, an anisotropic magneto-resistive resistor (AMR resistor), a giant magnetoresistance (GMR) multilayer film structure (or tunneling magnetoresistance (tunneling). The magnetoresistance (TMR) multilayer film structure) or a magnetic sensing element having a similar function such as a Hall element or the above combination is not limited in the present invention. In addition, the shape and size of the magnetic sensing element 210 in the drawings are only examples, and the present invention is not limited thereto.

In addition, in the embodiment, the first magnetoresistive unit 110 and the second magnetoresistive unit 120 respectively include at least one anisotropic magnetoresistance. 2A and 2B are diagrams for explaining the operation of the anisotropic magnetoresistance of Fig. 1A. Referring first to FIG. 2A, the anisotropic magnetoresistor 300 has a barber pole-like structure, that is, a plurality of shorting bars extending on the surface thereof with an inclination of 45 degrees with respect to the extending direction D of the anisotropic magnetoresistive resistor 300. (electrical shorting bar) 310, these shorting bars 310 are disposed on the ferromagnetic film 320 spaced apart from each other and in parallel, and the ferromagnetic film 320 is the main body of the anisotropic magnetoresistance 300, and the extending direction thereof is different. The extending direction D of the directional magnetoresistor 300. Further, the opposite ends of the ferromagnetic film 320 may be formed in a tip shape.

The anisotropic magnetoresistance 300 can first set its magnetization direction by the magnetization direction setting component 130 before starting to measure the external magnetic field H. The magnetization direction setting component 130 is, for example, a coil or a wire that can generate a magnetic field by energization. Metal sheet or conductor. In FIG. 2A, the magnetization direction setting member 130 can generate a magnetic field along the extending direction D by energization so that the anisotropic magnetoresistor 300 has the magnetization direction M.

Next, the magnetization direction setting element 130 is not energized, so that the anisotropic magnetoresistor 300 starts measuring the external magnetic field H. When there is no external magnetic field H, the magnetization direction M of the anisotropic magnetoresistor 300 is maintained in the extending direction D, at which time a current I is applied to cause the current I to flow from the left end of the anisotropic magnetoresistor 300 to the right end, and short circuit The current I in the vicinity of the rod 310 is perpendicular to the extending direction of the shorting bar 310, so that the current I in the vicinity of the shorting bar 310 is brought to the magnetization direction M by 45 degrees, and the resistance value of the anisotropic magnetoresistor 300 is R.

When there is an external magnetic field H directed in a direction perpendicular to the extending direction D, the magnetization direction M of the anisotropic magnetoresistance 300 is deflected outward in the direction of the magnetic field H, so that the angle between the magnetization direction and the current I flowing near the shorting bar is larger than At 45 degrees, the resistance value of the anisotropic magnetoresistor 300 has a change of -ΔR, that is, becomes R-ΔR, that is, the resistance value becomes small, wherein ΔR is greater than zero.

However, as shown in FIG. 2B, when the extending direction of the shorting bar 310 of FIG. 2B is set at a direction 90 degrees from the extending direction of the shorting bar 310 of FIG. 2A (the extending direction of the shorting bar 310 of FIG. 2B is still And the extension direction D of the anisotropic magnetoresistor 300 is 45 degrees), and when there is an external magnetic field H, in addition, the magnetic field H still deflects the magnetization direction M outward in the direction of the magnetic field H, and the magnetization direction M and the short circuit The angle of the current I flowing in the vicinity of the rod 310 may be less than 45 degrees, and the resistance value of the anisotropic magnetoresistor 300 may become R + ΔR, that is, the resistance value of the anisotropic magnetoresistor 300 becomes large.

Further, when the magnetization direction M of the anisotropic magnetoresistance 300 is set to the reverse direction shown in FIG. 2A by the magnetization direction setting member 130, the resistance value of the anisotropic magnetoresistor 300 of FIG. 2A after the external magnetic field H is thereafter Will become R+ΔR. Further, when the magnetization direction M of the anisotropic magnetoresistance 300 is set to the reverse direction shown in FIG. 2B by the magnetization direction setting element 130, the resistance of the anisotropic magnetoresistor 300 of FIG. 2B after the external magnetic field H is thereafter The value will become R-ΔR.

In summary, when the setting direction of the shorting bar 310 is changed, the resistance value R of the anisotropic magnetoresistor 300 corresponds to the change of the external magnetic field H from +ΔR to -ΔR or vice versa, and when the magnetization direction setting member 130 When the set magnetization direction M is changed to the reverse direction, the resistance value R of the anisotropic magnetoresistive resistor 300 corresponds to a change in the external magnetic field H from +ΔR to -ΔR or vice versa. When the direction of the external magnetic field H becomes reversed, the resistance value R of the anisotropic magnetoresistor 300 corresponding to the change of the external magnetic field H may change from +ΔR to -ΔR or vice versa. However, when the current I passing through the anisotropic magnetoresistor 300 becomes reversed, the resistance value R of the anisotropic magnetoresistive resistor 300 maintains the same sign as the external magnetic field H, that is, if it is +ΔR After changing the current direction, it is still +ΔR. If it is originally -ΔR, it is still -ΔR after changing the current direction.

According to the above principle, it is possible to determine when the anisotropic magnetoresistor 300 receives a certain component of the external magnetic field H by designing the extending direction D of the shorting bar 310 or the magnetization direction M set by the magnetization direction setting member 130. The direction of change of the resistance value R of the directional magnetoresistor 300, that is, the resistance value R becomes larger or smaller, for example, the amount of change is +ΔR or -ΔR.

Please refer to FIG. 3A to FIG. 4B . FIG. 3A and FIG. 4A are respectively schematic diagrams of magnetic field sensing devices at different times according to an embodiment of the present invention. In the magnetic field sensing device 100' in this embodiment, the magnetoresistive units (including the first magnetoresistive unit 110 and the second magnetoresistive unit 120) are electrically connected to at least one Wheatstone bridge at two different times. (In this embodiment, for example, the first Wheatstone full bridge of FIGS. 3A to 3C and the second Wheatstone full bridge of FIGS. 4A to 4C) to measure two different directions respectively (ie, The magnetic field components of the four directions D4 and the fifth direction D5), and the output of the at least one Wheatstone full bridge (for example, the aforementioned two types of Wheatstone full bridges) respectively correspond to two different directions (such as the fourth direction D4 and Two signals of the magnetic field component of the fifth direction D5).

In this embodiment, the first direction D1, the second direction D2, the third direction D3, the fourth direction D4, and the fifth direction D5 are different from each other, and the first direction D1, the second direction D2, and the third direction D3 are perpendicular to each other The fourth direction D4 is a sum vector direction of the first direction D1 and the second direction D2, and the fifth direction D5 is a difference vector direction of the first direction D1 and the second direction D2. Specifically, the first direction D1 and the second direction D2 are parallel to the surface S, the third direction D3 is perpendicular to the surface S, the fourth direction D4 and the fifth direction D5 are also parallel to the surface S, and the fourth direction D4 is perpendicular to the fifth The direction D5, the fourth direction D4 is at an angle of 45 degrees with the first direction D1 and the second direction D2, the fifth direction D5 is at an angle of 45 degrees with the second direction D2, and is 45 degrees with the reverse direction of the first direction D1. angle. In other embodiments, the three different directions D1, D2, and D3 do not have to be perpendicular to each other, and at least two directions may not be perpendicular to each other.

Specifically, in the present embodiment, each of the first magnetoresistive unit 110 and the second magnetoresistive units 120 includes at least one anisotropic magnetoresistance. The first magnetic sensing unit 110 includes a plurality of first magnetic resistors 112, 114, 116, 118 having a resistance value R. The second magnetic sensing unit 120 includes a plurality of second magnetoresistors 122, 124, 126, 128 having a resistance value R. The first magnetoresistances 112, 114, 116, 118 and the second magnetoresistive resistors 122, 124, 126, 128 are, for example, the anisotropic magnetoresistance 300 having an extending direction D as shown in FIGS. 2A and 2B or A combination of a plurality of anisotropic magnetoresistances 300 each having a plurality of shorting bars 310 extending obliquely with respect to the extending direction D.

The extending direction D of the anisotropic magnetoresistor 300 belonging to the first magnetoresistive unit 110 may be parallel to the second direction D2 or parallel to the side 212 of the magnetic sensing element 210 and parallel to the surface S. The extending direction D of the anisotropic magnetoresistance 300 belonging to the second magnetoresistive unit 120 may be parallel to the first direction D1 or parallel to the side surface 214 of the magnetic sensing element 210 and also parallel to the surface S.

Between the first magnetoresistors 112, 114, 116, 118 and the second magnetoresistive resistors 122, 124, 126, 128, the tips of the anisotropic magnetoresistance 300 may be connected by wires to create an electrical connection.

The magnetization direction setting element 132 covers the first magnetoresistances 112, 114, and the magnetization direction setting element 134 covers the first magnetoresistances 116, 118 to respectively set the magnetization directions of the first magnetoresistances 112, 114 and the first magnetoresistances 116, 118, The magnetization direction setting element 136 covers the second magnetoresistances 122, 124 to set the magnetization directions of the second magnetoresistances 122, 124, and the magnetization direction setting element 138 covers the second magnetoresistances 126, 128 to set the magnetization of the second magnetoresistors 126, 128. direction. The first magnetoresistances 112, 114, 116, 118 and the shorting bars 310 on the surface of the partial magnetoresistance of the second magnetoresistive resistors 122, 124, 126, 128 which are set to the same magnetization direction by the magnetization direction setting member 130. The tilt directions are opposite to each other.

It should be noted that the areas of the first magnetoresistive unit 110, the second magnetoresistive units 120 and the magnetization direction setting elements 130 covering the surface S are separated from the area of the magnetic sensing element 210 covered by the surface S. That is to say, the area covered by the magnetic sensing element 210 on the surface S does not overlap with the area covered by the first magnetoresistive unit 110, the second magnetoresistive unit 120, and the magnetization direction setting element 130 on the surface S.

In this embodiment, at least one of the above-mentioned Wheatstone bridges is a fixed connection mode of the Wheatstone bridge at one of two different times (for example, the first time or the second time). The magnetization direction setting element 130 sets the magnetization directions of the first magnetoresistive unit 110 and the second magnetoresistive unit 120 into two different combinations at the above two different times (for example, the first type of FIG. 3A to FIG. 3C). Wheatstone full bridge and the second Wheatstone bridge in Figures 4A to 4C, so that the Wheatstone bridge measures the magnetic fields in the fourth direction D4 and the fifth direction D5 at two different times. And outputting two signals corresponding to the magnetic field components of the fourth direction D4 and the fifth direction D5, respectively. A detailed description of the embodiments is as follows.

Referring to FIG. 3A at the first time of the above two different times, FIG. 3A illustrates a shorting bar of a magnetoresistance applied to a Wheatstone full bridge at a first time according to an embodiment of the present invention. A schematic diagram of setting the direction of the direction and the direction of magnetization. The first magnetoresistances 112, 114 are set by the magnetization direction setting member 132 so that the magnetization direction is directed in the forward direction of the second direction D2, and the first magnetoresistances 116, 118 are set by the magnetization direction setting member 134 so that the magnetization direction is directed to the second direction D2. The reverse direction, that is, the magnetization directions of a part of the first magnetoresistors (the first magnetoresistances 112, 114) and the other portion (the first magnetoresistances 116, 118) are set to face each other. The second magnetoresistances 122, 124 are set by the magnetization direction setting member 136 so that the magnetization direction is directed in the forward direction of the first direction D1, and the second magnetoresistances 126, 128 are set by the magnetization direction setting member 138 so that the magnetization direction is directed to the first direction D1. The reverse direction, that is, the magnetization directions of a part of the second magnetoresistors (the second magnetoresistances 122, 124) and the other portion (the second magnetoresistances 126, 128) are set to point to each other.

The first magnetoresistance 112 having the same magnetization direction (also covered by the magnetization direction setting member 132) but belonging to the different first magnetoresistive unit 110 and the tilting direction of the shorting bar 310 on the surface of the first magnetoresistive resistor 114 are opposite to each other, The same magnetization direction (also covered by the magnetization direction setting member 134) but the first magnetoresistance unit 110 belonging to the different first magnetoresistive unit 110 and the oblique direction of the shorting bar 310 on the surface of the first magnetoresistive resistor 118 are also opposite to each other. The tilt directions of the second magnetoresistive resistor 122 having the same magnetization direction (also covered by the magnetization direction setting member 136) but belonging to different second magnetoresistive units 120 and the shorting bars 310 on the surface of the second magnetoresistive resistor 124 are opposite to each other, The second magnetoresistance 126 having the same magnetization direction (also covered by the magnetization direction setting member 138) but belonging to the different second magnetoresistive unit 120 and the tilting direction of the shorting bar 310 on the surface of the second magnetoresistive resistor 128 are also opposite to each other .

Specifically, the first magnetoresistances 112 and 116 belonging to the same first magnetoresistive unit 110 have different magnetization directions, and the tilting directions of the shorting bars 310 on the surface are also different, belonging to the same first magnetoresistive unit 110. The first magnetoresistances 114, 118 have different magnetization directions, and the direction of inclination of the shorting bars 310 on the surface is also different. Similarly, the second magnetoresistances 122 and 126 belonging to the same second magnetoresistive unit 120 have different magnetization directions, and the tilting directions of the shorting bars 310 on the surface are also different, belonging to the same second magnetoresistive unit 120. The two magnetoresistances 124, 128 have different magnetization directions, and the tilt directions of the shorting bars 310 on the surface are also different. However, some of the first magnetoresistors 112, 114, 116 and 118 have opposite magnetization directions, and some of the second magnetoresistors 122, 124, 126 and 128 have opposite magnetization directions.

When the externally applied magnetic field is in the fourth direction D4, the first magnetoresistances 112, 116 induce a magnetic field component in the first direction D1 to respectively generate a resistance value change of +ΔR, and the first magnetoresistances 114, 118 sense The magnetic field component in the first direction D1 respectively produces a change in resistance value of -ΔR, and on the other hand, the second magnetoresistance 124, 128 induces a magnetic field component in the second direction D2 to generate a resistance value change of +ΔR, respectively. And the second magnetoresistive resistors 122, 126 sense the magnetic field component in the second direction D2 to respectively produce a resistance value change of -ΔR.

Please refer to FIG. 3B. FIG. 3B is an equivalent circuit diagram of the magnetic field sensing device of the embodiment of FIG. 3A when measuring the magnetic field component in the fourth direction. Due to the arrangement as described in the relevant paragraph of FIG. 3A (including the direction in which the shorting bar 310 is disposed, the direction in which the initial magnetization directions of the first magnetoresistive unit 110 and the second magnetoresistive unit 120 are set), the contact P1 and the contact P3, There is a resistance value change between +4ΔR and -2ΔR between P4, and a resistance value of -2ΔR and +2ΔR between the contact P2 and the contacts P3 and P4, respectively, and the above-mentioned contacts P1, P2, P3, P4 are, for example, It is an electrode. In this way, when a voltage difference is applied to the contacts P1 and P2, for example, the contact P1 receives the reference voltage VDD, and the contact P2 is coupled to the ground (or the contact P1 is opposite to the contact P2), and the contact P3 The voltage difference between the voltage value V1 and the voltage value V2 of the contact P4 may be an output signal, and the output signal is a differential signal whose magnitude corresponds to the magnitude of the magnetic field component in the fourth direction D4. Therefore, by knowing the magnitude of the output signal, the magnitude of the magnetic field component in the fourth direction D4 can be inferred.

In another embodiment, the contact P3 may receive the reference voltage VDD, and the contact P4 is coupled to the ground (or vice versa), and according to the voltage value of the contact P1 and the voltage value of the contact P2. The voltage difference between the output signals.

Please refer to FIG. 3C. FIG. 3C is an equivalent circuit diagram of the magnetic field sensing device of the embodiment of FIG. 3A when measuring the magnetic field component in the fifth direction. According to the arrangement of the magnetic field sensing device 100' described in FIG. 3A, when the externally applied magnetic field is in the fifth direction D5, the first magnetoresistances 112, 116 sense the magnetic field component in the opposite direction of the first direction D1. While the resistance values of -ΔR are respectively changed, the first magnetoresistances 114, 118 sense the magnetic field components in the opposite directions of the first direction D1 to respectively produce a resistance value change of +ΔR, and on the other hand, the second magnetoresistance 124 , 128 senses a magnetic field component in the second direction D2 to respectively generate a resistance value change of +ΔR, and the second magnetoresistive resistors 122, 126 induce a magnetic field component in the second direction D2 to respectively generate a resistance value of -ΔR. Variety. That is to say, the resistance value of -2ΔR and +2ΔR changes between the contact P1 and the contacts P3 and P4 respectively, and the resistance value change between the contact P2 and the contacts P3 and P4 does not change, and still has -2ΔR respectively. And the resistance value of +2ΔR changes, so the differential signal outputting the magnetic field component corresponding to the fifth direction D5 between the contacts P3 and P4 is zero.

Referring to FIG. 4A at a second time in two different times, FIG. 4A illustrates a shorting bar setting direction of a magnetoresistance applied to a Wheatstone full bridge at a second time according to an embodiment of the present invention. Schematic diagram of the direction in which the magnetization direction is set. Referring to the relevant paragraphs of Fig. 3A, the shorting bar setting direction of the magnetic field sensing device 100' remains unchanged, but the direction in which the magnetization direction is set is changed. The first magnetoresistances 112, 114 are set by the magnetization direction setting element 132 so that the magnetization direction is directed in the opposite direction to the second direction D2, and the first magnetoresistances 116, 118 are set by the magnetization direction setting element 134 so that the magnetization direction is directed to the second direction D2, That is, the magnetization directions of some of the first magnetoresistors (the first magnetoresistance 112, 114) and the other portion (the first magnetoresistive resistors 116, 118) are set to point to each other. The second magnetoresistances 122, 124 are set by the magnetization direction setting member 136 so that the magnetization direction is directed in the forward direction of the first direction D1, and the second magnetoresistances 126, 128 are set by the magnetization direction setting member 138 so that the magnetization direction is directed to the first direction D1. The reverse direction, that is, the magnetization directions of a part of the second magnetoresistors (the second magnetoresistances 122, 124) and the other portion (the second magnetoresistances 126, 128) are set to point to each other. The inclination directions of the shorting bars 310 on the surface of the partial magnetoresistance of the first magnetoresistances 112, 114, 116, 118 and the second magnetoresistances 122, 124, 126, 128 are still opposite to each other.

Please refer to FIG. 4B. FIG. 4B is an equivalent circuit diagram of the magnetic field sensing device of the embodiment of FIG. 4A when measuring the magnetic field component in the fourth direction. Due to the arrangement as described in the relevant paragraph of FIG. 4A (including the direction in which the shorting bar 310 is disposed, the direction in which the initial magnetization directions of the first magnetoresistive unit 110 and the second magnetoresistive unit 120 are set), the contact P1 and the contact P3, There is a resistance value change between -2ΔR and +2ΔR between P4, and a resistance value of -2ΔR and +2ΔR between the contact P2 and the contacts P3 and P4 respectively, so that a voltage is applied to the contacts P1 and P2. When the difference is small, for example, the contact P1 receives the reference voltage VDD, the contact P2 is coupled to the ground, and the output differential signal between the voltage value V1 of the contact P3 and the voltage value V2 of the contact P4 is zero.

Referring to FIG. 4C, FIG. 4C is an equivalent circuit diagram of the magnetic field sensing device of the embodiment of FIG. 4A when measuring the magnetic field component in the fifth direction. The embodiment described in the relevant paragraphs of FIGS. 3A to 4B (including the setting direction of the shorting bar 310, the setting direction of the initial magnetization direction of the first magnetoresistive unit 110 and the second magnetoresistive unit 120, and the associated resistance value change), The contact value between the contact P1 and the contacts P3 and P4 has a resistance value of +2ΔR and -2ΔR, respectively, and the resistance value between the contact P2 and the contacts P3 and P4 has -2ΔR and +2ΔR, respectively, so that When a voltage difference is applied to the contacts P1 and P2, the magnitude of the output signal between the voltage value V1 of the contact P3 and the voltage value V2 of the contact P4 corresponds to the magnitude of the magnetic field component in the fifth direction D5.

The magnetic field sensing device 100' in this embodiment is at least one of the two different times (the first time and the second time), the at least one Wheatstone full bridge (for example, FIG. 3A to FIG. 3C). The signal output by the first type of Wheatstone full bridge or the second Wheatstone full bridge of FIGS. 4A to 4C is the difference of the magnetic field components corresponding to one of the fourth direction D4 and the fifth direction D5. The signal, at this time, the difference signal of the magnetic field component corresponding to the other of the fourth direction D4 and the fifth direction D5 generated by the at least one Wheatstone bridge is zero.

The magnetic field sensing device 100' in this embodiment electrically connects the magnetization directions of the first magnetoresistive unit 110 and the second magnetoresistive unit 120 at two different times to electrically connect at least one type of Wheatstone. The full bridge is bridged to measure the magnetic field components of the fourth direction D4 and the fifth direction D5, respectively, and the two signals of the Wheatstone full bridge output corresponding to the magnetic field components of the fourth direction D4 and the fifth direction D5, respectively The magnetic sensing element 210 is used to measure the magnetic field component in the third direction. Therefore, the magnetic field sensing device 100' of the present embodiment can simultaneously realize three-dimensional magnetic field measurement and has a simplified structure, and thus can have a small volume, thereby achieving an advantage of increasing flexibility in application and reducing manufacturing cost.

Referring to FIG. 5A, FIG. 5A is a schematic diagram showing a direction in which a shorting bar is disposed and a direction in which a magnetization direction is set in a magnetic resistance of a magnetic field sensing device according to another embodiment of the present invention. In the embodiment of FIG. 5A, a switching circuit 160 (refer to FIG. 1B) is further included. The switching circuit 160 is disposed in the substrate 150, for example, and electrically connects the first magnetoresistive unit 110 and the second magnetoresistive unit 120. . These first magnetoresistive units 110 and these second magnetoresistive units 120 each form a Wheatstone half bridge structure. By switching the connection relationship of the contacts P5, P6, P7 and P8, the first magnetoresistive unit 110 and the second magnetoresistive unit 120 are electrically connected to the two types of Wheatstone bridges at two different times. The two kinds of Wheatstone full bridges respectively measure the magnetic field components of the fourth direction D4 and the fifth direction D5, and respectively output two signals corresponding to the magnetic field components of the fourth direction D4 and the fifth direction D5, as shown in FIG. 5B. Figure 5E shows. The above-mentioned contacts P5, P6, P7 and P8 are, for example, electrodes.

At the first of two different times, the switching circuit 160 connects the contact P5 to the contact P6 and the contact P7 to the contact P8. At this time, the related embodiment of the magnetic field measuring device 500 (including the shorting bar 310) The setting direction, the setting direction of the initial magnetization direction of the first magnetoresistive unit 110 and the second magnetoresistive unit 120, and the electrical connection manner are similar to those of the embodiment of FIG. 4A. Please refer to FIG. 5B, which is the embodiment of FIG. 5A. The equivalent circuit diagram of the magnetic field sensing device when measuring the magnetic field component in the fourth direction at the first time. At this time, the output differential signal corresponding to the fourth direction D4 is zero.

Referring to FIG. 5C, FIG. 5C is an equivalent circuit diagram of the magnetic field sensing device of the embodiment of FIG. 5A when the magnetic field component of the fifth direction is measured at the first time. Inductive to the magnetic field component in the fifth direction D5, the equivalent circuit output of FIG. 5C corresponds to a differential signal between the voltage value V1 and the voltage value V2, thereby measuring the magnitude of the magnetic field component in the fifth direction D5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the foregoing embodiments of FIGS. 4A to 4C, sufficient teachings, suggestions, and implementation descriptions have been obtained, and thus will not be described again.

In the second time of two different times, the switching circuit 160 connects the contact P5 to the contact P8, and the contact P7 to the contact P6, due to the direction in which the shorting bar 310 is disposed, the first magnetoresistive unit 110 and the second The setting direction of the initial magnetization direction of the magnetoresistive unit 120 is not changed, but the relationship of the electrical connection is changed. For the equivalent circuit of the magnetic field measuring device 500 at this time, please refer to FIG. 5D and FIG. 5E. 5D is an equivalent circuit diagram of measuring a magnetic field component in a fourth direction at a second time according to another embodiment of the present invention, inducing a magnetic field component in a fourth direction D4 and outputting a voltage value corresponding to a voltage value V1 and a voltage. The differential signal between the values V2 measures the magnitude of the magnetic field component in the fourth direction D4 by the magnitude of the differential signal. 5E is an equivalent circuit diagram of measuring a magnetic field component in a fifth direction at a second time by a magnetic field sensing device according to another embodiment of the present invention, wherein the Wheatstone full bridge circuit inducts a magnetic field in a fifth direction D5. The differential signal output by the component is 0. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the foregoing embodiments of FIGS. 1A to 5B, sufficient teachings, suggestions, and implementation descriptions have been obtained, and thus will not be described again.

Further, in the above-described embodiment, in any one of the above two different times, the number of Wheatstone full bridges electrically connected by the first magnetoresistive unit 110 and the second magnetoresistive unit 120 is one.

Therefore, in this embodiment, the magnetic field sensing device 500 electrically connects the first magnetoresistive unit 110 and the second magnetoresistive unit 120 to the at least one Wheatstone module at two different times by the switching circuit 160. a bridge for respectively measuring magnetic field components of the fourth direction D4 and the fifth direction D5, and causing such Wheatstone full bridge outputs two signals corresponding to the magnetic field components of the fourth direction D4 and the fifth direction D5, respectively The magnetic sensing component 210 is configured to measure a magnetic field component in a third direction. Therefore, the magnetic field sensing device 500 can simultaneously realize three-dimensional magnetic field measurement and has a simplified structure, and thus can have a small volume, and has the advantages of increasing flexibility in application and reducing manufacturing cost.

In summary, the magnetic field sensing device of the embodiment of the present invention uses a plurality of first magnetoresistance units whose magnetic field sensing axis is parallel to the first direction and a plurality of second magnetoresistances whose magnetic field sensing axis is parallel to the second direction. Unit and magnetic sensing element. The magnetic sensing component is configured to measure a magnetic field component in a third direction, and the first and second magnetoresistive elements are disposed adjacent to the magnetic sensing component and electrically connected to at least one Wheatstone full bridge at two different times , respectively, measuring the magnetic field components of the fourth direction and the fifth direction, and causing the Wheatstone full bridge output two signals corresponding to the magnetic field components of the fourth direction and the fifth direction, respectively, wherein the first direction, the first The two directions, the third direction, the fourth direction, and the fifth direction are different from each other, the fourth direction is a sum vector direction of the first direction and the second direction, and the fifth direction is a difference vector direction of the first direction and the second direction. Therefore, the magnetic field sensing device of the embodiment of the present invention can have a simplified structure and at the same time can realize three-dimensional magnetic field measurement, and thus can have a small volume, thereby achieving an advantage of increasing flexibility in application and reducing manufacturing cost.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

100, 100', 500‧‧‧ magnetic field sensing device

110‧‧‧First magnetoresistive unit

112, 114, 116, 118‧‧‧ first magnetoresistance

120‧‧‧second magnetoresistive unit

122, 124, 126, 128‧‧‧ second magnetoresistance

130, 132, 134, 136, 138‧‧‧ Magnetization direction setting components

150‧‧‧Substrate

160‧‧‧Switching circuit

210‧‧‧ Magnetic sensing components

212, 214‧‧‧ side

300‧‧‧ anisotropic magnetoresistance

310‧‧‧ Shorting bar

320‧‧‧ Ferromagnetic film

A-A‧‧‧ line

D1‧‧‧ first direction

D2‧‧‧ second direction

D3‧‧‧ third direction

D4‧‧‧ fourth direction

D5‧‧‧ fifth direction

D‧‧‧ Extension direction

M‧‧‧Magnetization direction

I‧‧‧current

H‧‧‧External magnetic field

S‧‧‧ surface

R‧‧‧ resistance value

ΔR‧‧‧Change in resistance value

1A is a top plan view of a magnetic field sensing device according to an embodiment of the present invention. 1B is a schematic cross-sectional view of the magnetic field sensing device of FIG. 1A taken along line A-A. 2A and 2B are diagrams for explaining the operation of the anisotropic magnetoresistance of Fig. 1A. FIG. 3A is a schematic view showing a direction in which a shorting bar is disposed and a direction in which a magnetization direction is applied to a magnetic resistance of a Wheatstone full bridge according to an embodiment of the present invention. FIG. 3B is an equivalent circuit diagram of the magnetic field sensing device of the embodiment of FIG. 3A when measuring the magnetic field component in the fourth direction. 3C is an equivalent circuit diagram of the magnetic field sensing device of the embodiment of FIG. 3A when measuring the magnetic field component in the fifth direction. 4A is a schematic view showing a direction in which a shorting bar is disposed and a direction in which a magnetization direction is applied to a magnetic resistance of a Wheatstone full bridge in a second time according to an embodiment of the present invention. 4B is an equivalent circuit diagram of the magnetic field sensing device of the embodiment of FIG. 4A when measuring the magnetic field component in the fourth direction. 4C is an equivalent circuit diagram of the magnetic field sensing device of the embodiment of FIG. 4A when measuring the magnetic field component in the fifth direction. FIG. 5A is a schematic view showing a direction in which a shorting bar is disposed and a direction in which a magnetization direction is set in a magnetic resistance of a magnetic field sensing device according to another embodiment of the present invention. 5B and 5C are respectively equivalent circuit diagrams when the magnetic field sensing device of the embodiment of FIG. 5A measures the magnetic field components of the fourth direction and the fifth direction at the first time. 5D and 5E are respectively equivalent circuit diagrams for measuring the magnetic field components of the fourth direction and the fifth direction at the second time by the magnetic field sensing device of the embodiment of FIG. 5A.

Claims (16)

A magnetic field sensing device, comprising: a plurality of first magnetoresistance units, wherein the magnetic field sensing axes of the first magnetoresistive units are parallel to a first direction; and a plurality of second magnetoresistive units, wherein the second magnets a magnetic field sensing axis of the resistor unit is parallel to a second direction; and a magnetic sensing component for measuring a magnetic field component in a third direction, wherein the first magnetoresistive unit and the second magnetoresistive unit are configured Next to the magnetic sensing element, the first magnetoresistive unit and the second magnetoresistive units are electrically connected to at least one Wheatstone bridge at two different times to respectively measure a fourth direction a first direction, the second direction, and a magnetic field component of a fifth direction, and the at least one Wheatstone full bridge output corresponding to the magnetic field components of the fourth direction and the fifth direction, respectively The third direction, the fourth direction, and the fifth direction are different from each other, and the fourth direction is a sum vector direction of the first direction and the second direction, and the fifth direction is the first direction and the second direction The difference vector direction. The magnetic field sensing device of claim 1, wherein at any one of the two different times, the signal output by the at least one Wheatstone bridge corresponds to the fourth direction and the fifth a differential signal of a magnetic field component in one of the directions, wherein the differential signal generated by the at least one Wheatstone full bridge corresponding to the magnetic field component of the other of the fourth direction and the fifth direction is zero. The magnetic field sensing device of claim 1, wherein the first magnetoresistive unit and the second magnetoresistive unit are respectively disposed on adjacent sides of the magnetic sensing component. The magnetic field sensing device of claim 1, further comprising a plurality of magnetization direction setting elements respectively disposed adjacent to the first magnetoresistive unit and the second magnetoresistance units to respectively set the first a magnetoresistive unit and a magnetization direction of the second magnetoresistive units. The magnetic field sensing device of claim 4, further comprising a substrate, wherein the magnetic sensing component, the first magnetoresistive unit, the second magnetoresistive unit, and the magnetization direction setting component are configured On a surface of the substrate, and the first magnetoresistive unit, the second magnetoresistive unit and the magnetization direction setting elements cover an area of the surface and an area of the magnetic sensing element covering the surface separate. The magnetic field sensing device of claim 4, wherein the at least one Wheatstone bridge is a fixed connection of a Wheatstone full bridge, and the magnetization direction setting elements are different in the two The time is set to two different combinations of the magnetization directions of the first magnetoresistive unit and the second magnetoresistive unit, so that the Wheatstone full bridge measures the fourth at the two different times. a direction and a magnetic field component of the fifth direction, and respectively outputting the two signals corresponding to the magnetic field components of the fourth direction and the fifth direction. The magnetic field sensing device of claim 4, wherein each of the first magnetoresistive units comprises a plurality of first magnetoresistors, and some of the first magnetoresistors have opposites to another portion The magnetization direction, and each of the second magnetoresistive units includes a plurality of second magnetoresistors, one of the second magnetoresistors having an opposite magnetization direction from the other portion. The magnetic field sensing device of claim 7, wherein a magnetization direction of one of the first magnetoresistors and another portion is set to face each other, and a part of the second magnetoresistors A part of the magnetization directions are set to point to each other. The magnetic field sensing device of claim 7, wherein a magnetization direction of one of the first magnetoresistors and another portion is set to point to each other, and a part of the second magnetoresistors and another portion The magnetization directions are set to point to each other. The magnetic field sensing device of claim 7, wherein the first magnetoresistors and the second magnetoresistors are anisotropic magnetoresistors having an extending direction, the first magnetoresistors and the The surfaces of the second magnetoresistance each have a plurality of shorting bars extending obliquely with respect to the extending direction, wherein the short circuits on the surface of the partial magnetoresistance having the same magnetization direction among the first magnetoresistors and the second magnetoresistors The inclination directions of the rods are opposite to each other. The magnetic field sensing device of claim 1, further comprising a switching circuit electrically connecting the first magnetoresistive unit and the second magnetoresistive units, wherein the at least one Wheatstone bridge is The two types of Wheatstone full bridges, the switching circuit electrically connecting the first magnetoresistance units and the second magnetoresistive units to the two types of Wheatstone full bridges at the two different times. The Wheatstone full bridge measures the magnetic field components of the fourth direction and the fifth direction, respectively, and outputs the two signals corresponding to the magnetic field components of the fourth direction and the fifth direction, respectively. The magnetic field sensing device of claim 1, wherein each of the first magnetoresistive unit and the second magnetoresistive unit comprises at least one anisotropic magnetoresistance. The magnetic field sensing device of claim 12, wherein an anisotropic magnetoresistance of the first magnetoresistance units extends parallel to the second direction and belongs to the second magnetoresistive units The direction of extension of the anisotropic magnetoresistance is parallel to the first direction. The magnetic field sensing device of claim 1, further comprising a substrate, wherein the magnetic sensing component, the first magnetoresistive unit and the second magnetoresistive unit are disposed on a surface of the substrate And the first direction is parallel to the second direction and the third direction is perpendicular to the surface. The magnetic field sensing device of claim 14, wherein the substrate is a semiconductor substrate, a glass substrate or a circuit substrate. The magnetic field sensing device of claim 1, wherein the first direction, the second direction, and the third direction are perpendicular to each other, and the fourth direction is perpendicular to the fifth direction, the fourth direction The first direction and the second direction are both sandwiched by 45 degrees.