CN110426658A - A kind of vertical sensitive Magnetic Sensor of the wide-range fed back on closed loop core - Google Patents

Abstract

The invention discloses a closed-loop on-core feedback wide-range vertical sensitive magnetic sensor, which includes a silicon-based substrate, a flux guide, a magneto-sensitive resistor, a signal feedback coil, an operational amplifier and a power amplifier. The in-position signal feedback coil is set on the vertical sensitive magnetic sensor chip. When there is a feedback current, the magneto-sensitive resistor above the signal feedback coil will generate magnetic field signals of equal size and opposite direction in the direction of the sensitive axis, which respectively cancel the original signal magnetic field and form a closed loop. The feedback structure effectively improves the output linearity of the sensor, improves the measurement accuracy, and reduces power consumption; the distance between the magneto-sensitive resistor and the flux guide is different, so that the horizontal magnetic field components received by the magneto-sensitive resistor are different, and the large magnetic field and the The purpose of detecting different ranges of small magnetic fields.

Description

A Closed-loop On-Core Feedback Wide Range Vertically Sensitive Magnetic Sensor

technical field

The invention belongs to the technical field of magnetic sensors, and relates to a closed-loop on-core feedback wide-range vertical sensitive magnetic sensor.

Background technique

With the rapid development of the field of magnetic sensors, their applications are becoming more and more extensive. The current vertical magnetic sensors are widely used in consumer electronics such as mobile phones and electronic compass mobile devices. Such products require smaller package sizes and higher Measure stability.

Most of the existing vertically sensitive magnetic sensors are Z-axis package design, and the Z-axis package is to package the sensitive axis of the sensor chip on the vertical and horizontal plane, such as patent CN 102426344 A, which is an invention patent of a three-axis magnetic field sensor. A method of packaging and integrating three sensors is adopted, in which the sensor of the Z axis is placed on a vertical plane to measure the magnetic field in the vertical direction. The sensor made by this method has a large volume, high packaging cost, complicated process, low stability and easy fracture of the package. The name of patent CN103995240B is a magnetoresistive Z-axis gradient sensor chip, which uses a flux guide to place the Z-axis magnetic field component in the XY plane. But this invention mainly uses the flux guider to guide the Z-axis magnetic field in the XY plane to measure the Z-axis gradient. In order to ensure the sensitivity of the existing sensors composed of magnetic sensitive elements, the detection range of the magnetic field is mostly within plus or minus 10Gs, and the detection ability for larger magnetic fields is insufficient.

Although there are single-core integrated vertically sensitive magnetic sensors, they are currently open-loop designs. For example, the name of the application number 201820341886.X is a push-pull vertically sensitive magnetic sensor, which uses a flux guide The Z-axis magnetic field of the Z-axis is converted into the leakage magnetic field component in the plane, and the magnetic field detection in the vertical direction is realized. However, in the case of measuring a large magnetic field, the magneto-sensitive resistor is easy to magnetic saturation and the hysteresis is large during measurement, which is very difficult. To a large extent, it affects the measurement bandwidth, measurement accuracy and linearity of the sensor, and the open-loop design has poor linearity and low measurement accuracy, which is difficult to meet the needs of modern industries.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the prior art solutions, and provide a closed-loop on-core feedback wide range vertical sensitive magnetic sensor.

The invention includes a silicon-based substrate, a flux guide, four identical magnetoresistors, a signal feedback coil, an operational amplifier and a power amplifier;

The flux guide is a strip-shaped structure, and the four magnetoresistors are all arranged on the same silicon-based substrate, and two shielded magnetoresistors for reference are arranged directly below the flux guide. A magnetoresistor is arranged on the left and right sides of the flux guide respectively. The two magnetoresistors are left-right symmetrical about the flux guide. The left and right sides of the flux guider; the flux guider induces the vertical magnetic field signal to the in-plane direction, generates an in-plane magnetic field component at the magnetoresistors on both sides of it, and generates in the directions of the two magnetoresistor sensitive axes The signal magnetic field components are equal in magnitude and opposite in direction;

The symmetrical magnetoresistors on the left and right sides of the flux guider form a set of half-bridges, and the two shielded magnetoresistors set directly below the flux guider for reference form another set of half-bridges. The magneto-sensitive resistors together form a Wheatstone bridge structure with push-pull output; the signal feedback coil is a U-shaped structure with two sides parallel to each other. The signal feedback coil is set on the silicon-based substrate below the magneto-sensitive resistor. They are respectively arranged directly under the magneto-sensitive resistors on the left and right sides of the flux guide. When the feedback current is passed, the signal feedback coil generates magnetic field signals of equal magnitude and opposite direction at the sensitive axis direction of the magneto-sensitive resistors on both sides of the flux guide. ;

A detection resistor is arranged between the output terminal of the signal feedback coil and the ground terminal; the output terminal of the Wheatstone bridge is connected to the input terminal of the operational amplifier, and the output terminal of the operational amplifier is connected to the input terminal of the power amplifier, and the power The output end of the amplifier is connected to the signal feedback coil to form a closed-loop feedback structure.

The present invention may also include a silicon-based substrate, a flux guide, six identical magnetoresistors, two signal feedback coils, an operational amplifier, and a power amplifier; it is characterized in that: the flux guide is strip-shaped structure, and the six magnetoresistors are all arranged on the same silicon-based substrate, two shielded magnetoresistors for reference are arranged directly under the flux guide, and the left and right sides of the flux guide are respectively arranged Two magnetoresistors, the two magnetoresistors close to the left and right sides of the flux director form a pair, and the two magnetoresistors away from the left and right sides of the flux guide form a pair, each pair of magnetoresistors They are all symmetrical about the flux guider, the sensitive axes of the six magnetoresistors have the same direction, and the position configuration of the flux guider and the six magnetoresistors can detect the magnetic field signal in the vertical plane; the two signal feedback coils are U-shaped structures , a feedback coil of U-shaped structure is arranged on the silicon-based substrate below a pair of magnetoresistors close to the left and right sides of the flux guider, and the other feedback coil of U-shaped structure is arranged away from the left and right sides of the flux guider The two sides of the U-shaped structure are parallel to each other on the silicon-based substrate below the pair of magnetoresistors on the side, and are respectively arranged directly under the two pairs of magnetoresistors on both sides of the flux guide; A pair of magnetoresistors and two shielded reference magnetoresistors set directly below the flux guide form a Wheatstone bridge structure with push-pull output, which is used for the detection of magnetic field signals in small-scale vertical planes; away from A pair of magneto-resistors of the flux guide and two shielded magneto-resistors set directly below the flux guide for reference form another push-pull output Wheatstone bridge structure for large-range vertical plane Detection of magnetic field signals; two pairs of Wheatstone bridge structure design meet the needs of sensor chips for different range detection of magnetic field signals in vertical planes;

The flux guide induces the vertical magnetic field signal to the in-plane direction and generates magnetic flux leakage components in the directions of the two pairs of magnetoresistor sensitive axes on the left and right sides of the flux guide respectively, and the vertical magnetic field signal passes through the flux guide After induction, magnetic flux leakage components of equal size and opposite directions are generated in the direction of the first pair of magnetoresistor sensitive axes, and magnetic flux leakage components of equal size and opposite direction are generated in the direction of the second pair of magnetoresistor sensitive axes; through feedback When the current is flowing, the signal feedback coils below the pair of magnetoresistors near the left and right sides of the flux guide will generate feedback of the magnetic flux leakage component that cancels the direction of the sensitive axis of the magnetoresistors in the direction of the sensitive axis of the two magnetoresistors above it. Magnetic field; the signal feedback coil below the pair of magnetoresistors far away from the left and right sides of the flux guide generates a magnetic leakage component feedback magnetic field in the direction of the sensitive axis of the two magnetoresistors above it that cancels the direction of the sensitive axis of the magnetoresistor ;

The output terminals of the two Wheatstone bridges are connected to the input terminal of the operational amplifier through a switch. The function of the switch is to select one of the two groups of Wheatstone bridges as the detection bridge, which indirectly has the function of selecting the measurement range; the operational amplifier Output after amplifying the signal amplitude, the output terminal of the operational amplifier is connected to the input terminal of the power amplifier, the output terminal of the power amplifier is connected to the signal feedback coil, the other end of the feedback coil is connected in series with the resistance under test, and the other end of the resistance under test grounded.

Preferably, the flux guide is made of nickel-based, cobalt-based or iron-based soft magnetic materials.

Preferably, the magneto-resistor is selected from giant magneto-resistance resistance or tunnel junction magneto-resistance.

Preferably, the signal feedback coil is made of non-magnetic, low-resistance, good-conductivity metal silver, copper, aluminum, gold-titanium or alloys thereof.

In the present invention, an in-position signal feedback coil is provided on the core of the push-pull vertical sensitive magnetic sensor chip, and when the feedback current passes through, two pairs of magnetoresistor sensitive axis directions above the signal feedback coil generate magnetic field signals of equal magnitude and opposite direction, Respectively offset the original signal magnetic field to form a closed-loop feedback structure, which can effectively improve the linearity of the sensor output, improve the measurement accuracy, and reduce power consumption; it is also possible to use two sets of magneto-sensitive resistors with different distances from the flux guide to make the two sets of magneto-sensitive The horizontal direction magnetic field components received by the resistors are different, and two pairs of push-pull bridges formed by six identical magnetoresistors realize the purpose of detecting different ranges of large magnetic fields and small magnetic fields respectively.

Description of drawings

Fig. 1 is a structural schematic diagram of Embodiment 1 of the present invention;

Fig. 2 is an overall system structure diagram of Embodiment 1 of the present invention;

3 is a schematic diagram of a vertical magnetic field induced by a flux guide under the action of an external magnetic field in Embodiment 1 of the present invention;

Fig. 4 is a schematic diagram of a push-pull Wheatstone bridge in Embodiment 1 of the present invention;

5 is a schematic diagram of the feedback magnetic field canceling the original magnetic field under the action of the signal feedback coil in Embodiment 1 of the present invention;

6 is a schematic diagram of a Wheatstone bridge state under the action of a signal feedback coil in Embodiment 1 of the present invention;

Fig. 7 is a schematic structural diagram of Embodiment 2 of the present invention;

FIG. 8 is an overall system structure diagram of Embodiment 2 of the present invention;

9 is a schematic diagram of a vertical magnetic field induced by a flux guide under the action of an external magnetic field in Embodiment 2 of the present invention;

10 is a schematic diagram of a push-pull Wheatstone bridge in Embodiment 2 of the present invention;

11 is a schematic diagram of the feedback magnetic field canceling the original magnetic field under the action of the signal feedback coil in the second embodiment of the present invention;

FIG. 12 is a schematic diagram of a Wheatstone bridge state under the action of a signal feedback coil in Embodiment 2 of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Embodiment one:

As shown in Figure 1, a closed-loop on-core feedback wide-range vertical sensitive magnetic sensor includes a silicon-based substrate 1, a flux guide 2, four identical magnetoresistors 3, a signal feedback coil 4, and an operational amplifier. and power amplifier.

The flux guide 2 has a strip-shaped structure, and is arranged on the same silicon-based substrate 1 with the four magnetoresistors 3, and two shielded magnetoresistors for reference are arranged directly below the flux guide 2 , the left and right sides of the flux guide 2 are respectively provided with a magneto-resistor, the two magneto-resistors are left-right symmetrical about the flux guide 2, the directions of the sensitive axes of the two magneto-resistors 3 are on the same horizontal line and have the same direction, Both are perpendicular to the left and right sides of the flux guide 2 .

As shown in Figure 3, the flux guide 2 induces the vertical magnetic field signal to the in-plane direction, generates an in-plane magnetic field component at the magnetoresistors on both sides of it, and generates a The signal magnetic field components are equal in magnitude and opposite in direction.

As shown in Figure 4, the symmetrical magnetoresistors on the left and right sides of the flux guider 2 form a set of half-bridges, and the two shielded magnetoresistors 3 for reference arranged directly below the flux guider 2 form another set of half-bridges. A half-bridge is formed, and four magnetoresistors 3 together form a push-pull output Wheatstone bridge structure.

As shown in Figure 5, the signal feedback coil 4 is a U-shaped structure, and the two sides of the U-shaped structure are parallel to each other. The two parallel sides of the coil 4 are arranged directly below the magnetoresistors on the left and right sides of the flux guide 2, and the signal feedback coil 4 is generated in the direction of the sensitive axis of the magnetoresistors on both sides of the flux guide when the feedback current is passed. Magnetic field signals of equal magnitude and opposite directions.

As shown in Figure 2, a detection resistor is arranged between the output terminal of the signal feedback coil 4 and the ground terminal; the output terminal of the Wheatstone bridge is connected to the input terminal of the operational amplifier, and the output terminal of the operational amplifier is connected to the power amplifier. The input end and the output end of the power amplifier are connected to the signal feedback coil 4 to form a closed-loop feedback structure.

In this implementation, the flux guide 2 is made of nickel-based, cobalt-based or iron-based soft magnetic materials. Soft magnetic materials have strong magnetic permeability, especially soft magnetic alloys such as nickel-iron or cobalt-iron materials. The magneto-sensitive resistor 3 is selected from a giant magnetoresistance resistor or a tunnel junction magnetoresistance. Both giant magnetoresistance and tunnel junction magnetoresistance have bipolar characteristics, which are convenient for the formation and measurement of push-pull bridges. The signal feedback coil 4 is made of non-magnetic, low-resistance, good-conductivity metal silver, copper, aluminum or gold. Avoid sensor damage caused by high-resistance metal heating.

The operational amplifier selected in this embodiment is the AD623 model of ADI Company. The function of the operational amplifier is to amplify the output voltage value of the sensor, because the voltage generated by the sensor chip is a tiny voltage, generally at the millivolt level, which is not convenient for subsequent processing. The magnification of the operational amplifier can be magnified up to 1000 times, and adjusting the appropriate magnification is convenient for signal analysis, processing and measurement.

In this embodiment, the power amplifier can choose the LM3886 power amplifier of National Semiconductor of the United States. As the name suggests, the power amplifier is used to amplify the power, and the most important thing is to amplify the current. The power amplifier in the present invention improves the drive capability of the sensor output signal, and the drive signal feedback coil 4.

In this embodiment, the flux guider 2 can generate the leakage magnetic field component in the horizontal plane under the action of the Z-axis magnetic field in the vertical direction on the one hand, and can shield and reduce the interference of the magnetic field component in the horizontal direction at the same time; Magnetic field components in different directions are generated at the sensitive resistor 3, and the magnetoresistance resistance values of the two pairs of magnetic sensitive resistors 3 change in different sizes to make the Wheatstone bridge form a push-pull output; the differential voltage output by the Wheatstone bridge is passed through the operational amplifier module and power The amplification module converts the current signal into the signal feedback coil 4, and the two parallel sides of the signal feedback coil 4 pass the feedback current to generate a circular induced magnetic field, and the magnetic field component of the horizontal tangent at the top of the circular induced magnetic field reacts on the flux guide 2 Generate leakage magnetic field components in the horizontal plane, and then offset the measured magnetic field, until the magnetic field intensity received by the magneto-sensitive resistor 3 in the direction of its sensitive axis approaches zero, at this time the Wheatstone bridge is in a balanced state, and then measure the feedback coil The magnitude of the feedback current can be obtained by the voltage across the resistance Rm to be measured connected in series; the feedback current is proportional to the measured magnetic field, and the magnitude of the measured magnetic field can be further obtained through the measured feedback current magnitude.

As shown in Figure 6, in the push-pull bridge composed of R1, R2, R3 and R4, when the sensor is subjected to a magnetic field perpendicular to the silicon-based substrate 1, the flux guide 2 decomposes the magnetic field into R1 and R2 In the direction of the horizontal sensitive axis, the resistance values of R3 and R4 remain unchanged due to the shielding, and due to the formed push-pull structure, the resistance values of R1 and R2 increase one and the other decrease, and the increase and decrease resistance values are the same, assuming Under the influence of the magnetic field to be measured, the change in resistance of the magneto-sensitive resistor 3 is ΔR, and the output of the bridge at this time is Due to the existence of the signal feedback coil 4, when the sensor outputs an electrical signal, a feedback current is generated on the signal feedback coil 4, the feedback current generates a feedback magnetic field, and the feedback magnetic field reacts on the magnetoresistor 3 to cancel the original magnetic field, thereby making the magnetoresistor 3 The combined magnetic field is almost zero and reaches a balanced state.

The feedback system formed by zero magnetic flux measurement can track to 0.2 microseconds, that is, the frequency can reach 5MHZ; the feedback system can effectively reduce external interference and improve linearity, which greatly improves the accuracy of measurement.

Embodiment two:

As shown in Figure 7, the difference between this embodiment and Embodiment 1 is that: two pairs of magneto-sensitive resistors are arranged on the left and right sides of the flux guide 2, and the two pairs of magneto-sensitive resistors are symmetrical to each other with respect to the left and right sides of the flux guide; The six magnetoresistors are all of the same specification and placed side by side in parallel.

As shown in Figures 8 and 10, a pair of magnetoresistors close to the left and right sides of the flux guider 2 and two shielded magnetoresistors used for reference directly below the flux guider 2 form a push-pull output. Wheatstone bridge structure, the bridge detects a large magnetic field component and high sensitivity, and can be used for small-range magnetic field signal detection on a vertical plane, away from the other pair of magnetoresistors and flux guides on the left and right sides of the flux guide 2 The two shielded magnetoresistors 3 for reference set directly below the device 2 form another push-pull output Wheatstone bridge structure. The bridge detects a small magnetic field component and low sensitivity, and can be used for a large range of vertical planes Magnetic field signal detection, two pairs of Wheatstone bridges are designed to meet the detection requirements of the sensor chip for different ranges of magnetic field signals in the vertical plane.

Among them, R1, R2, R3 and R4 form a group of Wheatstone bridges, wherein R1 and R2 are connected to form a group of half bridges, and R3 and R4 are connected to form another group of half bridges. The supply voltage is provided between R1 and R3, and the junction of R2 and R4 is connected to ground. The connection between R1 and R2 and the connection between R3 and R4 leads to the output terminal of the sensor;

R5, R6, R3 and R4 form a set of Wheatstone bridges, wherein R5 and R6 are connected to form a set of half bridges, and R3 and R4 are connected to form another set of half bridges. The supply voltage is provided between R5 and R3, and the connection between R6 and R4 is connected to ground. The connection between R5 and R6 and the connection between R3 and R4 leads to the output terminal of the sensor.

The output terminals of the two Wheatstone bridges are connected to the input terminal of the operational amplifier through a switch, (the function of the switch is to select one of the two groups of Wheatstone bridges as the detection bridge, which indirectly has the function of selecting the measurement range) Operation The amplifier outputs after amplifying the signal amplitude. The output terminal of the operational amplifier is connected to the input terminal of the power amplifier, and the output terminal of the power amplifier is connected to the signal feedback coil. The other end of the ground.

As shown in Figure 11, another signal feedback coil 4 is arranged below the pair of magnetoresistors 3 on the left and right sides of the flux guider 2, and the energized signal feedback coil 4 produces a magnitude in the direction of the sensitive axis of the two magnetoresistors. Equal and opposite magnetic field signals.

As shown in Figure 9, under the action of the Z-axis magnetic field in the vertical direction, the flux guide 2 generates a leakage magnetic field component in the horizontal plane. effect. Similarly, assuming a vertically upward uniform magnetic field H, under the action of the uniform magnetic field H, positive and negative magnetic charges are evenly distributed on the upper and lower surfaces of the flux guide 2, and the magnetoresistor 3 that is closer to the flux guide 2 receives a stronger magnetic field Components, magnetoresistors farther away from the flux guide 2 receive weaker magnetic field components.

The magnetoresistor under the flux guide 2 is covered and shielded by the soft magnetic material flux guide 2, and is not affected by the external magnetic field. At this time, the two shielded magnetoresistors are used as reference resistors, respectively connected to the flux guide 2 The magnetoresistors on the left and right sides form a bridge structure. That is, R1, R2, R3, R4 form a set of push-pull bridges, and R3, R4, R5, R6 form another set of push-pull bridges.

When the measured vertical magnetic field is small, the flux guide 2 converts the vertical magnetic field into a horizontal magnetic field by using the magnetoresistors R1 and R2 close to both sides of the flux guide 2, and simultaneously forms R1, R2, R3, The R4 push-pull bridge also forms a push-pull structure. The bridge output sensitivity at this time is:

It can be seen from the formula that the sensitivity of the sensor in this embodiment is half of the sensitivity of the sensor in the four-arm push-pull bridge. However, the sensor chip made in this way is smaller in size, which is more in line with the miniaturization requirements of modern sensors.

If the measured magnetic field is relatively large, a Wheatstone bridge structure is formed by using magneto-sensitive resistors R5 and R6 away from both sides of the flux guider 2 and shielded R3 and R4. At this time, because R5 and R6 are far away from the flux guide 2, the horizontal magnetic field strength of the flux guide 2 here is relatively small, so the horizontal magnetic flux leakage at this place is much smaller than that at R1 and R2, which is suitable for use for the detection of large magnetic fields.

As shown in Figure 12, in the push-pull bridge composed of R5, R6, R3 and R4, when the sensor is subjected to a magnetic field perpendicular to the silicon-based substrate 1, the flux guide 2 decomposes the magnetic field into R5 and R6 In the direction of the horizontal sensitive axis, the resistance values of R3 and R4 remain unchanged due to the shielding, and the resistance values of the resistors R5 and R6 due to the formed push-pull structure increase one and decrease the other, and the increased and decreased resistance values are the same, assuming Under the influence of the magnetic field to be measured, the resistance value of the magneto-sensitive resistor 3 changes by ΔR ¹ , and the output of the bridge at this time is Due to the existence of the signal feedback coil 4, when the sensor outputs an electrical signal, a feedback current is generated on the signal feedback coil 4, the feedback current generates a feedback magnetic field, and the feedback magnetic field reacts on the magnetoresistor 3 to cancel the original magnetic field, thereby making the magnetoresistor 3 The combined magnetic field is almost zero and reaches a balanced state.

It is worth noting that: in accompanying drawings 4, 6, 10 and 12, the obliquely filled arrows point to indicate the direction of the original magnetic field to which the magnetoresistor 3 is subjected; the mesh line filled arrows point to indicate the signal feedback coil 4 The direction of the resulting feedback magnetic field.

Compared with the traditional external circuit system feedback structure, the on-core on-site feedback structure requires a greatly reduced feedback current and a greatly reduced coil impedance, thereby greatly reducing the power consumption of the sensor system.

The advantage of the present invention is that by setting the position signal feedback coil on the core of the push-pull type vertically sensitive magnetic sensor chip, when there is a feedback current, the two pairs of magnetoresistors 3 above the signal feedback coil 4 in the direction of the sensitive axis will produce directions of equal size. The opposite magnetic field signals respectively cancel the original signal magnetic field to form a closed-loop feedback structure, which effectively improves the linearity of the sensor output, improves the measurement accuracy, and reduces power consumption; the two sets of magneto-sensitive resistors have different distances from the flux guide 2, thereby making The horizontal direction magnetic field components received by the two groups of magneto-sensitive resistors 3 are different, and two pairs of push-pull bridges formed by six identical magneto-sensitive resistors 3 can respectively detect large and small magnetic fields in different ranges.

It will be apparent to those skilled in the art that the invention is not limited to the details of the above-described exemplary embodiments, but that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Accordingly, the embodiments should be regarded in all points of view as exemplary and not restrictive, the scope of the invention being defined by the appended claims rather than the foregoing description, and it is therefore intended that the scope of the invention be defined by the appended claims rather than by the foregoing description. All changes within the meaning and range of equivalents of the elements are embraced in the present invention. Any reference sign in a claim should not be construed as limiting the claim concerned.

Claims (8)

1. A wide-range vertically sensitive magnetic sensor with feedback on a closed-loop core includes a silicon-based substrate, a flux guide, four identical magnetoresistors, a signal feedback coil, an operational amplifier, and a power amplifier; It is characterized in that: the flux guide is a strip structure, and the four magnetoresistors are all arranged on the same silicon substrate, and two shielded reference sensors are arranged directly below the flux guide. Magnetoresistors, one magnetoresistor is arranged on the left and right sides of the flux guide, the two magnetoresistors are symmetrical about the flux guide, the sensitive axes of the two magnetoresistors are on the same horizontal line and have the same direction, Both are perpendicular to the left and right sides of the flux guide; the flux guide induces the vertical magnetic field signal to the in-plane direction, and generates an in-plane magnetic field component at the magnetoresistors on both sides, and the two magnetoresistor sensitive axes The signal magnetic field components generated in the direction are equal in magnitude and opposite in direction; The symmetrical magnetoresistors on the left and right sides of the flux guider form a set of half-bridges, and the two shielded magnetoresistors set directly below the flux guider for reference form another set of half-bridges. The magneto-sensitive resistors together form a Wheatstone bridge structure with push-pull output; the signal feedback coil is a U-shaped structure with two sides parallel to each other. The signal feedback coil is set on the silicon-based substrate below the magneto-sensitive resistor. They are respectively arranged directly under the magneto-sensitive resistors on the left and right sides of the flux guide. When the feedback current is passed, the signal feedback coil generates magnetic field signals of equal magnitude and opposite direction at the sensitive axis direction of the magneto-sensitive resistors on both sides of the flux guide. ; A detection resistor is arranged between the output terminal of the signal feedback coil and the ground terminal; the output terminal of the Wheatstone bridge is connected to the input terminal of the operational amplifier, and the output terminal of the operational amplifier is connected to the input terminal of the power amplifier, and the power The output end of the amplifier is connected to the signal feedback coil to form a closed-loop feedback structure. 2. A closed-loop on-core feedback wide-range vertical sensitive magnetic sensor according to claim 1, characterized in that: said flux guide is made of nickel-based, cobalt-based or iron-based soft magnetic materials. 3. A closed-loop on-core feedback wide-range vertical sensitive magnetic sensor according to claim 1, characterized in that: the magneto-resistor is selected from giant magnetoresistance resistance or tunnel junction magnetoresistance. 4. The wide-range vertical sensitive magnetic sensor with feedback on a closed-loop type core according to claim 1, wherein the signal feedback coil is made of non-magnetic, low-resistance, good-conductivity metallic silver, copper, Made of aluminum, gold titanium or their alloys. 5. A wide-range vertical sensitive magnetic sensor with feedback on a closed-loop core, including a silicon-based substrate, a flux guide, six identical magnetoresistors, two signal feedback coils, an operational amplifier and a power amplifier; its characteristics In that: the flux guide is a strip structure, and the six magnetoresistors are all arranged on the same silicon substrate, and two shielded magnetoresistors for reference are arranged directly below the flux guide. Resistors, two magnetoresistors are set on the left and right sides of the flux guide respectively, the two magnetoresistors close to the left and right sides of the flux guide form a pair, and the two magnetoresistors far away from the left and right sides of the flux guide The magnetoresistors form a pair, and each pair of magnetoresistors is left-right symmetrical about the flux guider. The directions of the sensitive axes of the six magnetoresistors are the same, and the position configuration of the flux guider and the six magnetoresistors can detect the Magnetic field signal; two signal feedback coils are both U-shaped structures, one U-shaped structure feedback coil is set on the silicon-based substrate under a pair of magnetoresistors near the left and right sides of the flux guide, and the other U-shaped structure The feedback coil is set on the silicon base substrate below a pair of magnetoresistors far away from the left and right sides of the flux guide. The two sides of the U-shaped structure are parallel to each other and are respectively arranged on two pairs of Directly below the magnetoresistor; a pair of magnetoresistors close to the flux guide and two shielded magnetoresistors set directly below the flux guide for reference form a push-pull output Wheatstone bridge structure, It is used for the detection of magnetic field signals in a small range vertical plane; a pair of magnetoresistors away from the flux guide and two shielded magnetoresistors for reference set directly below the flux guide form another push-pull output The Wheatstone bridge structure is used for the detection of magnetic field signals in a large vertical plane; the design of two pairs of Wheatstone bridge structures meets the needs of sensor chips for different range detection of magnetic field signals in vertical planes; The flux guide induces the vertical magnetic field signal to the in-plane direction and generates magnetic flux leakage components respectively in the direction of the two pairs of magnetoresistor sensitive axes on the left and right sides of the flux guide, and the vertical magnetic field signal passes through the flux guide After induction, magnetic flux leakage components of equal size and opposite directions are generated in the direction of the first pair of magnetoresistor sensitive axes, and magnetic flux leakage components of equal size and opposite direction are generated in the direction of the second pair of magnetoresistor sensitive axes; through feedback When the current is flowing, the signal feedback coils below the pair of magnetoresistors near the left and right sides of the flux guide will generate feedback of the magnetic flux leakage component that cancels the direction of the sensitive axis of the magnetoresistors in the direction of the sensitive axis of the two magnetoresistors above it. Magnetic field; the signal feedback coil below the pair of magnetoresistors far away from the left and right sides of the flux guide generates a magnetic leakage component feedback magnetic field in the direction of the sensitive axis of the two magnetoresistors above it that cancels the direction of the sensitive axis of the magnetoresistor ; The output terminals of the two Wheatstone bridges are connected to the input terminal of the operational amplifier through a switch. The function of the switch is to select one of the two groups of Wheatstone bridges as the detection bridge, which indirectly has the function of selecting the measurement range; the operational amplifier Output after amplifying the signal amplitude, the output terminal of the operational amplifier is connected to the input terminal of the power amplifier, the output terminal of the power amplifier is connected to the signal feedback coil, the other end of the feedback coil is connected in series with the resistance under test, and the other end of the resistance under test grounded. 6 . A closed-loop on-core feedback wide-range vertical sensitive magnetic sensor according to claim 5 , wherein the flux guide is made of nickel-based, cobalt-based or iron-based soft magnetic materials. 7. A closed-loop on-core feedback wide-range vertical sensitive magnetic sensor according to claim 5, characterized in that: the magneto-resistor is a giant magnetoresistance resistor or a tunnel junction magnetoresistance. 8. The wide-range vertical sensitive magnetic sensor with feedback on a closed-loop type core according to claim 5, wherein the signal feedback coil is made of non-magnetic, low-resistance, good-conductivity metallic silver, copper, Made of aluminum, gold titanium or their alloys.