Tunnel magnetoresistive sensor temperature compensation method based on alternating reference magnetic field

Abstract

The invention relates to a tunnel magnetoresistive sensor temperature compensation method and device based on an alternating reference magnetic field, computer equipment, a storage medium and a computer program product. The method comprises the following steps: acquiring surrounding magnetic field information, an alternating current signal amplification coefficient, a reference alternating current, an alternating coil parameter and a current temperature error voltage of the tunnel magnetoresistive sensor; separating to-be-measured magnetic field information and reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters; and according to the reference magnetic field information, the to-be-measured magnetic field information, the AC signal amplification coefficient and the current temperature error voltage, adjusting the reference sensitivity of the tunnel magnetoresistive sensor to obtain temperature compensation information. By adopting the method, the sensitivity loss of the tunnel magnetoresistive sensor can be reduced.

Description

Technical Field

[0001] The present application relates to the field of sensor technology, and in particular to a method, device, computer equipment, storage medium and computer program product for temperature compensation of a tunnel magnetoresistive sensor based on an alternating reference magnetic field. Background Art

[0002] Tunnel magnetoresistance (TMR) sensors are a new type of magnetoresistive sensor device. With its advantages of high sensitivity, low power consumption and miniaturization, they are suitable for various industries such as automobiles, healthcare, industrial automation, and electricity. TMR sensors use the tunneling magnetoresistance effect in magnetic tunnel junctions to achieve high-precision detection even in weak magnetic fields.

[0003] Changes in ambient temperature can cause output fluctuations in TMR sensors, known as temperature drift errors. Significant temperature drift errors severely limit their applicability in high-precision measurement environments. As temperature increases, the coercivity difference between the two ferromagnetic layers in the magnetic tunnel junction decreases, causing the magnetic moments to tend to align more easily. At the same time, oxidation on the surface of the ferromagnetic layer also causes spin scattering. As temperature increases, spin flip scattering associated with the oxide layer becomes more pronounced, shortening the spin diffusion length of charge carriers. These effects weaken the magnetoresistance effect, resulting in a significant decrease in the tunneling magnetoresistance, showing a significant negative temperature characteristic. In addition, even though the TMR sensor uses a Wheatstone bridge structure to balance the temperature drift error to a certain extent, the resistance values ​​of the four bridge arms of the bridge cannot remain consistent as the preparation process and material properties cannot be guaranteed to be completely consistent. The above factors cause the TMR sensor to exhibit significant temperature drift in an environment with temperature fluctuations, resulting in sensitivity loss. Summary of the invention

[0004] Based on this, it is necessary to provide a tunnel magnetoresistance sensor temperature compensation method, device, computer equipment, computer-readable storage medium and computer program product based on an alternating reference magnetic field to reduce the sensitivity loss of the tunnel magnetoresistance sensor in order to address the above technical problems.

[0005] In a first aspect, the present application provides a method for temperature compensation of a tunnel magnetoresistive sensor based on an alternating reference magnetic field, comprising:

[0006] Obtain the surrounding magnetic field information, AC signal amplification factor, reference alternating current, alternating coil parameters and current temperature error voltage of the tunnel magnetoresistive sensor;

[0007] Separating the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters;

[0008] The reference sensitivity of the tunnel magnetoresistance sensor is adjusted according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain temperature compensation information.

[0009] In one embodiment, the reference sensitivity of the tunnel magnetoresistance sensor is adjusted according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain the temperature compensation information, including:

[0010] Dividing the AC signal amplification factor by the reference magnetic field information to obtain the AC sensor sensitivity;

[0011] Determining the sensitivity of the DC sensor according to the DC induced voltage relationship between the magnetic field information to be measured and the current temperature error voltage;

[0012] The reference sensitivity is adjusted according to the difference between the sensitivity of the AC sensor and the sensitivity of the DC sensor to determine the temperature compensation information of the tunnel magnetoresistance sensor.

[0013] In one embodiment, determining the DC sensor sensitivity according to the DC induced voltage relationship between the magnetic field information to be measured and the current temperature error voltage includes:

[0014] Obtaining a sensor output voltage of the tunnel magnetoresistive sensor;

[0015] separating a DC output voltage from the sensor output voltage;

[0016] The DC output voltage and the current temperature error voltage are adjusted according to the magnetic field information to be measured to determine the sensitivity of the DC sensor.

[0017] In one embodiment, the DC output voltage and the current temperature error voltage are adjusted according to the magnetic field information to be measured to determine the sensitivity of the DC sensor, including:

[0018] Using the current temperature error voltage, adjusting the DC output voltage of the sensor to obtain an adjusted DC output error;

[0019] The measured magnetic field information is used to adjust the change gradient of the adjusted DC output error to determine the sensitivity of the DC sensor.

[0020] In one embodiment, the step of adjusting the reference sensitivity according to the difference between the sensitivity of the AC sensor and the sensitivity of the DC sensor to determine the temperature compensation information of the tunnel magnetoresistance sensor includes:

[0021] Calculating the ratio between the sensitivity of the AC sensor and the sensitivity of the DC sensor to obtain a sensitivity ratio coefficient;

[0022] The reference sensitivity of the tunnel magnetoresistive sensor is adjusted using the sensitivity ratio coefficient to obtain the temperature compensation information.

[0023] In one embodiment, separating the measured magnetic field information and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters includes:

[0024] Determining a reference magnetic field amplitude and a reference magnetic field frequency according to the reference alternating current and the alternating coil parameters;

[0025] generating a magnetic field separation parameter according to the reference magnetic field amplitude and the reference magnetic field frequency;

[0026] The magnetic field information to be measured and the reference magnetic field information are separated from the surrounding magnetic field information according to the magnetic field separation parameter.

[0027] In a second aspect, the present application further provides a tunnel magnetoresistive sensor temperature compensation device based on an alternating reference magnetic field, comprising:

[0028] An information acquisition module is used to obtain the surrounding magnetic field information of the tunnel magnetoresistive sensor, the AC signal amplification factor, the reference alternating current, the alternating coil parameters and the current temperature error voltage;

[0029] A magnetic field separation module, used to separate the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters;

[0030] The compensation acquisition module is used to adjust the reference sensitivity of the tunnel magnetoresistive sensor according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain temperature compensation information.

[0031] In a third aspect, the present application further provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:

[0032] Obtain the surrounding magnetic field information, AC signal amplification factor, reference alternating current, alternating coil parameters and current temperature error voltage of the tunnel magnetoresistive sensor;

[0033] Separating the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters;

[0034] The reference sensitivity of the tunnel magnetoresistance sensor is adjusted according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain temperature compensation information.

[0035] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the following steps are implemented:

[0036] Obtain the surrounding magnetic field information, AC signal amplification factor, reference alternating current, alternating coil parameters and current temperature error voltage of the tunnel magnetoresistive sensor;

[0037] Separating the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters;

[0038] The reference sensitivity of the tunnel magnetoresistance sensor is adjusted according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain temperature compensation information.

[0039] In a fifth aspect, the present application further provides a computer program product, including a computer program, which implements the following steps when executed by a processor:

[0040] Obtain the surrounding magnetic field information, AC signal amplification factor, reference alternating current, alternating coil parameters and current temperature error voltage of the tunnel magnetoresistive sensor;

[0041] Separating the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters;

[0042] The reference sensitivity of the tunnel magnetoresistance sensor is adjusted according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain temperature compensation information.

[0043] The above-mentioned method, device, computer equipment, storage medium and computer program product for temperature compensation of a tunnel magnetoresistance sensor based on an alternating reference magnetic field first obtain the surrounding magnetic field information, AC signal amplification factor, reference alternating current, alternating coil parameters and current temperature error voltage of the tunnel magnetoresistance sensor. By collecting basic parameters, the current working state and environmental influencing factors of the tunnel magnetoresistance sensor can be fully understood, and the necessary raw data support is provided for subsequent signal separation and compensation adjustment, so that the compensation method can deal with temperature influence in a targeted manner; then, according to the reference alternating current and alternating coil parameters, the magnetic field information to be measured and the reference magnetic field information are separated from the surrounding magnetic field information, and the surrounding magnetic field of the sensor environment is obtained. The measured magnetic field and reference magnetic field information are extracted from the information, and the environmental factors are effectively separated from the measurement signal, which can ensure the accuracy of the temperature compensation method, so that the sensor only adjusts the sensitivity of the actual magnetic field measurement information without being affected by other interference factors; finally, according to the reference magnetic field information, the measured magnetic field information, the AC signal amplification factor and the current temperature error voltage, the reference sensitivity of the tunnel magnetoresistance sensor is adjusted to obtain the temperature compensation information. By adjusting the reference sensitivity of the tunnel magnetoresistance sensor, temperature compensation can be performed in real time, so that the output of the tunnel magnetoresistance sensor is more stable, and the sensitivity is corrected according to the actual temperature error voltage, thereby reducing the influence of temperature drift on the measurement accuracy and improving the reliability of the sensor. In the above method, the alternating reference magnetic field and real-time sensitivity adjustment are used to effectively reduce the influence of temperature changes on the sensitivity of the tunnel magnetoresistance sensor, realize the compensation of temperature drift errors, improve the measurement accuracy and stability of the sensor in a temperature fluctuation environment, and enhance its environmental adaptability. High-precision measurement can be maintained without additional hardware compensation equipment, thereby improving the reliability and wide application of tunnel magnetoresistance sensors in high temperature and changing environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related technologies, the drawings required for use in the embodiments or the related technical descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] FIG1 is a schematic flow chart of a method for temperature compensation of a tunnel magnetoresistive sensor based on an alternating reference magnetic field in one embodiment;

[0046] FIG2 is a schematic flow chart of a method for temperature compensation of a tunnel magnetoresistive sensor based on an alternating reference magnetic field in another embodiment;

[0047] FIG3 is a schematic diagram of a Wheatstone bridge structure of a tunnel magnetoresistive sensor in one embodiment;

[0048] FIG4 is a schematic diagram of a process for determining temperature compensation information based on an AC reference magnetic field in one embodiment;

[0049] FIG5 is a structural block diagram of a temperature compensation device for a tunnel magnetoresistive sensor based on an alternating reference magnetic field in one embodiment;

[0050] FIG. 6 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0052] In one embodiment, as shown in FIG1 , a method for temperature compensation of a tunnel magnetoresistive sensor based on an alternating reference magnetic field is provided. This embodiment uses the method applied to a terminal as an example. It is understandable that the method can also be applied to a server, and can also be applied to a system including a terminal and a server, and is implemented through the interaction between the terminal and the server. Among them, the terminal can be, but is not limited to, various personal computers, laptops, smart phones, and tablet computers. The server can be implemented as an independent server or a server cluster consisting of multiple servers. In this embodiment, the method includes the following steps:

[0053] Step S101 , obtaining the surrounding magnetic field information, AC signal amplification factor, reference alternating current, alternating coil parameters and current temperature error voltage of the tunnel magnetoresistive sensor.

[0054] Among them, the surrounding magnetic field information refers to the data information of the magnetic field to be measured and the reference magnetic field in the environment where the tunnel magnetoresistance sensor is located, which is directly measured by the tunnel magnetoresistance sensor; the AC signal amplification factor refers to the proportional coefficient used when amplifying the AC signal to improve the signal detection accuracy, and more accurate measurement is achieved by amplifying weak signals; the reference alternating current refers to the current that generates a reference alternating magnetic field, usually an alternating current of a specific frequency, which provides a stable reference magnetic field; the alternating coil parameters refer to the coil-related parameters that generate the alternating magnetic field, such as the number of coil turns, materials, etc., which affect the magnetic field strength and frequency; the current temperature error voltage refers to the sensor output voltage deviation caused by changes in ambient temperature, which is used for subsequent temperature compensation calculations.

[0055] Exemplarily, the terminal can obtain these parameters through a sensor detection unit. First, the terminal collects real-time data of the surrounding magnetic field from the output end of the tunnel magnetoresistance sensor, obtains the amplified AC signal through an internal or external amplifier module, and calculates and records its amplification factor. At the same time, the terminal sets and detects the parameters of the reference alternating current and alternating coil to ensure the stability of the reference magnetic field. In addition, the terminal can obtain the current temperature error voltage information through the temperature sensor module, and store it in the data processing module in combination with the above parameters to provide accurate basic data for subsequent temperature compensation.

[0056] Step S102 : separating the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters.

[0057] The reference alternating current is a current used to generate a stable reference alternating magnetic field, which works together with the alternating coil parameters to generate a reference magnetic field with a fixed frequency so as to be distinguished from the magnetic field to be measured.

[0058] Exemplarily, the terminal first applies an alternating current of a specific frequency through an alternating coil to generate a reference magnetic field of a known frequency. Then, the terminal uses the total magnetic field signal detected by the tunnel magnetoresistance sensor, and uses phase-sensitive detection or synchronous detection technology to separate the signal component of the reference magnetic field frequency from the surrounding magnetic field data, thereby obtaining the magnetic field information to be measured and the reference magnetic field information. The separation process can ensure that the subsequent sensitivity adjustment is only for the magnetic field data to be measured, making the temperature compensation process more accurate.

[0059] Step S103, adjusting the reference sensitivity of the tunnel magnetoresistive sensor according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain temperature compensation information.

[0060] Among them, the magnetic field information to be measured is the unknown magnetic field data in the environment, which reflects the magnetic field strength and direction in the actual application scenario of the tunnel magnetoresistance sensor; the current temperature error voltage is the sensor output voltage deviation caused by the change in ambient temperature, which is used to calculate the sensitivity change caused by temperature.

[0061] For example, the terminal analyzes the sensitivity changes of the tunnel magnetoresistance sensor at different temperatures in real time based on the difference between the reference magnetic field information and the magnetic field information to be measured, combined with the AC signal amplification factor. The terminal uses the current temperature error voltage as a compensation factor and applies it to the sensitivity adjustment algorithm to accurately calibrate the reference sensitivity of the tunnel magnetoresistance sensor. Through this adjustment, the terminal can generate temperature compensation information that adapts to the current temperature environment, making the output signal of the tunnel magnetoresistance sensor more stable and reducing the measurement error caused by temperature drift.

[0062] In the above-mentioned temperature compensation method of the tunnel magnetoresistance sensor based on the alternating reference magnetic field, firstly, the surrounding magnetic field information, AC signal amplification factor, reference alternating current, alternating coil parameters and current temperature error voltage of the tunnel magnetoresistance sensor are obtained. By collecting the basic parameters, the current working state and environmental influencing factors of the tunnel magnetoresistance sensor can be fully understood, and the necessary raw data support is provided for the subsequent signal separation and compensation adjustment, so that the compensation method can deal with the temperature influence in a targeted manner; then, according to the reference alternating current and alternating coil parameters, the magnetic field information to be measured and the reference magnetic field information are separated from the surrounding magnetic field information, and the magnetic field to be measured and the reference magnetic field information are extracted from the surrounding magnetic field information of the sensor environment. The reference magnetic field information effectively separates the environmental factors from the measurement signal, which can ensure the accuracy of the temperature compensation method, so that the sensor only adjusts the sensitivity of the actual magnetic field measurement information without being affected by other interference factors; finally, according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage, the reference sensitivity of the tunnel magnetoresistance sensor is adjusted to obtain the temperature compensation information. By adjusting the reference sensitivity of the tunnel magnetoresistance sensor, temperature compensation can be performed in real time, making the output of the tunnel magnetoresistance sensor more stable, and the sensitivity is corrected according to the actual temperature error voltage, thereby reducing the influence of temperature drift on the measurement accuracy and improving the reliability of the sensor. In the above method, the alternating reference magnetic field and real-time sensitivity adjustment are used to effectively reduce the influence of temperature changes on the sensitivity of the tunnel magnetoresistance sensor, realize the compensation of temperature drift errors, improve the measurement accuracy and stability of the sensor in a temperature fluctuation environment, and enhance its environmental adaptability. High-precision measurement can be maintained without additional hardware compensation equipment, thereby improving the reliability and wide application of tunnel magnetoresistance sensors in high temperature and changing environments.

[0063] In an exemplary embodiment, the above-mentioned step S103 adjusts the reference sensitivity of the tunnel magnetoresistance sensor according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain temperature compensation information, and also includes: dividing the AC signal amplification factor by the reference magnetic field information to obtain the AC sensor sensitivity; determining the DC sensor sensitivity according to the DC induced voltage relationship between the magnetic field information to be measured and the current temperature error voltage; adjusting the reference sensitivity according to the difference between the AC sensor sensitivity and the DC sensor sensitivity to determine the temperature compensation information of the tunnel magnetoresistance sensor.

[0064] Among them, the DC induced voltage relationship between the measured magnetic field information and the current temperature error voltage is used to determine the sensitivity of the DC sensor, which reflects the response of the sensor to temperature changes under static conditions and serves as a benchmark for temperature compensation. The difference between the sensitivity of the AC sensor and the sensitivity of the DC sensor indicates the difference in the dynamic and static responses of the sensor under different temperature conditions. The reference sensitivity is adjusted based on this difference to generate temperature compensation information that adapts to the current environment.

[0065] Exemplarily, the terminal first calculates the AC sensitivity of the tunnel magnetoresistance sensor by dividing the AC signal amplification factor by the reference magnetic field information. Next, the terminal uses the magnetic field information to be measured and the current temperature error voltage to obtain the DC sensitivity through the DC signal relationship. Then, the terminal compares the AC sensitivity with the DC sensitivity, and adjusts the reference sensitivity of the tunnel magnetoresistance sensor according to the difference between the two to generate temperature compensation information.

[0066] Specifically, ,in, is the AC sensitivity of the tunnel magnetoresistance sensor; T is the temperature parameter; A is the AC signal amplification factor; is the magnetic field amplitude of the reference magnetic field.

[0067] In this embodiment, by comparing and adjusting the AC and DC sensitivities, the influence of temperature change on the sensitivity of the tunnel magnetoresistive sensor is effectively compensated, the measurement stability of the sensor in different temperature environments is improved, and the output is made more accurate and reliable.

[0068] In an exemplary embodiment, the above-mentioned determination of the DC sensor sensitivity based on the DC induced voltage relationship between the magnetic field information to be measured and the current temperature error voltage also includes: obtaining the sensor output voltage of the tunnel magnetoresistance sensor; separating the DC output voltage from the sensor output voltage; and adjusting the DC output voltage and the current temperature error voltage according to the magnetic field information to be measured to determine the DC sensor sensitivity.

[0069] Among them, the sensor output voltage of the tunnel magnetoresistance sensor refers to the voltage signal output by the sensor after detecting the magnetic field, which contains the comprehensive information of the alternating and direct current components; the direct current output voltage is the static component separated from the sensor output voltage, reflecting the stable signal of the magnetic field to be measured at a specific temperature.

[0070] Exemplarily, the terminal first obtains the sensor output voltage of the tunnel magnetoresistive sensor, which contains the components of the alternating signal and the DC signal. Next, the terminal separates the DC component in the output voltage through filtering or phase-sensitive detection technology to obtain the DC output voltage. Then, the terminal corrects the DC output voltage according to the magnetic field information to be measured, and adjusts the sensor response in combination with the current temperature error voltage to determine the sensitivity of the DC sensor.

[0071] In this embodiment, by extracting and correcting the DC component in the sensor output voltage and combining it with temperature compensation information, the sensitivity of the tunnel magnetoresistance sensor in a static magnetic field is successfully determined accurately, thereby improving the measurement stability in a temperature-changing environment and ensuring the accuracy and reliability of the sensor.

[0072] In an exemplary embodiment, the DC output voltage and the current temperature error voltage are adjusted according to the magnetic field information to be measured to determine the sensitivity of the DC sensor, and the method also includes: using the current temperature error voltage to adjust the DC output voltage of the sensor to obtain an adjusted DC output error; using the magnetic field information to be measured to adjust the gradient of the change of the adjusted DC output error to determine the sensitivity of the DC sensor.

[0073] Among them, the measured magnetic field information is used to further adjust the change gradient of the correction error to make the sensor sensitivity more in line with the actual measurement needs; the change gradient adjustment is to correct the rate at which the error changes with the magnetic field or temperature to improve the accuracy of the sensitivity calculation.

[0074] Exemplarily, the terminal first uses the current temperature error voltage to correct the DC output voltage of the sensor to obtain an adjusted DC output error, thereby eliminating the initial deviation caused by the temperature and making the output signal more consistent with the actual magnetic field information to be measured. Next, the terminal uses the surrounding magnetic field information to correct the change gradient of the adjusted DC output error, thereby more accurately analyzing the change trend of the error under different magnetic field strengths or temperature conditions. Through this gradient correction, the terminal can accurately determine the sensitivity of the DC sensor, making it more adaptable to changes in temperature and magnetic field.

[0075] Specifically, ,in, is the DC sensitivity of the tunnel magnetoresistive sensor; is the DC output voltage of the tunnel magnetoresistive sensor; is the error voltage of the tunnel magnetoresistive sensor; is the magnetic field strength of the magnetic field to be measured.

[0076] In this embodiment, by performing temperature compensation and gradient adjustment on the DC output error, the DC sensitivity of the tunnel magnetoresistive sensor is accurately determined, so that it can maintain high measurement accuracy in an environment with temperature fluctuations, thereby enhancing the stability and reliability of the sensor.

[0077] In an exemplary embodiment, the reference sensitivity is adjusted according to the difference between the AC sensor sensitivity and the DC sensor sensitivity to determine the temperature compensation information of the tunnel magnetoresistance sensor, and also includes: calculating the ratio between the AC sensor sensitivity and the DC sensor sensitivity to obtain a sensitivity ratio coefficient; and using the sensitivity ratio coefficient to adjust the reference sensitivity of the tunnel magnetoresistance sensor to obtain temperature compensation information.

[0078] Among them, the sensitivity ratio coefficient is a proportional coefficient calculated by the ratio between AC and DC sensitivities, which is used to measure the sensitivity difference of the tunnel magnetoresistance sensor at different frequencies and serves as the basis for adjusting the reference sensitivity; the reference sensitivity is the sensitivity benchmark of the tunnel magnetoresistance sensor under standard temperature conditions, which is corrected by combining with the sensitivity ratio coefficient to ensure the accurate response of the sensor under temperature fluctuations; the temperature compensation information is the final correction parameter, which is used to compensate for the influence of temperature drift on the sensor sensitivity in real time.

[0079] For example, the terminal first calculates the ratio of the AC sensor sensitivity to the DC sensor sensitivity to obtain a sensitivity ratio coefficient. Then, the terminal uses the ratio coefficient to correct the reference sensitivity of the tunnel magnetoresistance sensor to generate temperature compensation information. Through this adjustment process, the terminal can dynamically correct the change of sensor sensitivity under different temperature conditions, so that the tunnel magnetoresistance sensor has higher temperature adaptability in practical applications.

[0080] Specifically, .

[0081] in, is the temperature compensation information; is the 0℃ reference sensitivity of the tunnel magnetoresistive sensor.

[0082] In this embodiment, by calculating the sensitivity ratio coefficient and adjusting the reference sensitivity accordingly, the influence of temperature change on the measurement accuracy of the tunnel magnetoresistive sensor is effectively reduced, so that the sensor can still maintain stable measurement accuracy and reliability in a temperature fluctuation environment.

[0083] In an exemplary embodiment, the above-mentioned step S102 separates the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters, and also includes: determining the reference magnetic field amplitude and the reference magnetic field frequency according to the reference alternating current and the alternating coil parameters; generating a magnetic field separation parameter according to the reference magnetic field amplitude and the reference magnetic field frequency; and separating the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the magnetic field separation parameters.

[0084] Among them, the reference magnetic field amplitude refers to the magnetic field strength jointly generated by the alternating coil and the reference alternating current, which reflects the maximum fluctuation range of the reference magnetic field; the reference magnetic field frequency is the frequency at which the reference magnetic field changes over time, which is used to distinguish magnetic field signals of other frequencies; the magnetic field separation parameter is a separation parameter set generated by the reference magnetic field amplitude and frequency. This parameter set can accurately identify and separate different magnetic field signals in the surrounding environment, ensuring the independence of the magnetic field to be measured and the reference magnetic field.

[0085] Exemplarily, the terminal first calculates the amplitude and frequency of the reference magnetic field based on the reference alternating current and alternating coil parameters. Next, the terminal uses these magnetic field separation parameters to analyze and process the surrounding magnetic field information collected by the tunnel magnetoresistive sensor, and distinguishes the magnetic field signal to be measured from the reference magnetic field signal, thereby ensuring the accuracy of subsequent data processing.

[0086] Specifically, .

[0087] Wherein, B is the surrounding magnetic field information, that is, the magnetic field intensity output by the tunnel magnetoresistance sensor; is the reference magnetic field signal, that is, the magnetic field strength of the reference magnetic field; is the magnetic field amplitude of the reference magnetic field; is the magnetic field frequency of the reference magnetic field; t is the time parameter.

[0088] In this embodiment, by determining the amplitude and frequency of the reference magnetic field and generating magnetic field separation parameters, the tunnel magnetoresistive sensor can accurately extract the magnetic field information to be measured from the complex surrounding magnetic field. This separation technology significantly improves the measurement accuracy, allowing the sensor to maintain high-resolution detection of the target magnetic field in a multi-interference environment.

[0089] In another exemplary embodiment, as shown in FIG2 , the present application provides a tunnel magnetoresistive sensor temperature compensation method based on an alternating reference magnetic field, comprising:

[0090] Step 1: Input alternating current into the micro coil , generating an alternating reference magnetic field .

[0091] Step 2: Measure the alternating reference magnetic field and the magnetic field to be measured by using a tunnel magnetoresistance sensor , get the sensor output voltage output by the tunnel magnetoresistance sensor .

[0092] Step three, obtain the functional expression of the sensor output voltage through graph analysis.

[0093] Step 4: Based on the functional expression of the sensor output voltage, separate the DC sensitivity of the tunnel magnetoresistive sensor AC sensitivity of tunnel magnetoresistive sensors .

[0094] Step five: calculate temperature compensation information.

[0095] It should be noted that the tunnel magnetoresistance sensor adopts a Wheatstone bridge structure and is provided with a flux concentrator, as shown in Figure 3. Each magnetic component (the small rectangle R in the figure) is composed of multiple magnetic tunnel junctions connected in series, and the number of magnetic tunnel junctions in series of the four magnetic components is the same. The dotted rectangle is a magnetic flux concentrator, and the gap in the middle of the magnetic flux concentrator is a magnetic concentrating area. Rref1 and Rref2 are reference resistors, located below the magnetic flux concentrator, shielded by the magnetic flux concentrator, and their resistance values ​​do not change with the external magnetic field. The other two magnetic resistors R1 and R1 are located in the gap in the middle of the magnetic flux concentrator, and their magnetic resistance values ​​change with the external magnetic field. Under this structure, the output voltage of the tunnel magnetoresistance sensor can be expressed as:

[0096]

[0097] Among them, V out is the output voltage, V cc is the input supply voltage, R ref1 and R ref2 The reference resistance is R0, the initial resistance of the variable R1 and R1 magnetoresistance is also R0, and its resistance value changes with the external magnetic field is ΔR.

[0098] The variable reference external magnetic field is generated by a fixed frequency AC current passing through a tiny coil. The reference magnetic field frequency is the same as the applied AC frequency. The reference magnetic field and the external magnetic field to be measured act together on the tunnel magnetoresistive sensor. The sensor output signal is amplified by an amplifier. Through phase-sensitive testing, the output signal caused by the fixed frequency reference magnetic field can be separated. Based on this signal, the real-time sensitivity change result of the tunnel magnetoresistive sensor can be obtained. According to the sensitivity change result, the output value of the tunnel magnetoresistive sensor is adjusted to compensate for the error caused by temperature drift.

[0099] Within the measuring range of the TMR sensor, the output voltage can be expressed as: .

[0100] Where S is the sensor sensitivity, B is the magnetic field around the sensor, and V0 is the sensor error voltage. Temperature affects both the sensitivity S and error voltage V0 of the tunnel magnetoresistive sensor. When the ambient temperature changes, the output voltage can be expressed as: .

[0101] As shown in FIG4 , it is a flow chart for determining temperature compensation information based on an AC reference magnetic field, which is specifically as follows:

[0102] When the applied amplitude is ,frequency of Alternating reference magnetic field, the magnetic field around the tunnel magnetoresistance can be expressed as:

[0103]

[0104] in, is the magnetic field to be measured. In this case, the output voltage can be expressed as:

[0105]

[0106] frequency The AC output voltage can be expressed as:

[0107]

[0108] Where A is the AC signal amplification factor. Through synchronous detection technology, the sensitivity of the tunnel magnetoresistance sensor corresponding to the AC signal can be expressed as: .

[0109] The DC voltage output of the magnetic field to be measured is: .

[0110] The sensitivity corresponding to DC can be expressed as: .

[0111] The bias voltage also changes with temperature, so the zero voltage needs to be calibrated before sensitivity calculation. Finally, the sensitivity compensation formula can be expressed as:

[0112]

[0113] in, is the 0℃ reference sensitivity of the tunnel magnetoresistive sensor.

[0114] In this embodiment, the temperature drift of the tunnel magnetoresistance sensor can be effectively solved, and the repeatability and linearity of the sensor can be improved. At the same time, there is no need to establish a high-precision tunnel magnetoresistance temperature model, which improves the energy efficiency of practical applications.

[0115] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0116] Based on the same inventive concept, the embodiment of the present application also provides a tunnel magnetoresistance sensor temperature compensation device based on an alternating reference magnetic field for implementing the tunnel magnetoresistance sensor temperature compensation method based on an alternating reference magnetic field. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations of one or more embodiments of the tunnel magnetoresistance sensor temperature compensation device based on an alternating reference magnetic field provided below can refer to the limitations of the tunnel magnetoresistance sensor temperature compensation method based on an alternating reference magnetic field above, and will not be repeated here.

[0117] In an exemplary embodiment, as shown in FIG5 , a temperature compensation device for a tunnel magnetoresistive sensor based on an alternating reference magnetic field is provided, comprising: an information acquisition module 501, a magnetic field separation module 502 and a compensation acquisition module 503, wherein:

[0118] The information acquisition module 501 is used to acquire the surrounding magnetic field information, AC signal amplification factor, reference alternating current, alternating coil parameters and current temperature error voltage of the tunnel magnetoresistive sensor;

[0119] A magnetic field separation module 502 is used to separate the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters;

[0120] The compensation acquisition module 503 is used to adjust the reference sensitivity of the tunnel magnetoresistive sensor according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain temperature compensation information.

[0121] In one of the embodiments, the compensation acquisition module 503 is also used to divide the AC signal amplification factor by the reference magnetic field information to obtain the AC sensor sensitivity; determine the DC sensor sensitivity based on the DC induced voltage relationship between the magnetic field information to be measured and the current temperature error voltage; adjust the reference sensitivity based on the difference between the AC sensor sensitivity and the DC sensor sensitivity to determine the temperature compensation information of the tunnel magnetoresistance sensor.

[0122] In one embodiment, the compensation acquisition module 503 is also used to obtain the sensor output voltage of the tunnel magnetoresistance sensor; separate the DC output voltage from the sensor output voltage; adjust the DC output voltage and the current temperature error voltage according to the magnetic field information to be measured to determine the sensitivity of the DC sensor.

[0123] In one embodiment, the compensation acquisition module 503 is further used to use the current temperature error voltage to adjust the DC output voltage of the sensor to obtain the adjusted DC output error; and use the magnetic field information to be measured to adjust the change gradient of the adjusted DC output error to determine the sensitivity of the DC sensor.

[0124] In one embodiment, the compensation acquisition module 503 is further used to calculate the ratio between the sensitivity of the AC sensor and the sensitivity of the DC sensor to obtain a sensitivity ratio coefficient; and use the sensitivity ratio coefficient to adjust the reference sensitivity of the tunnel magnetoresistance sensor to obtain temperature compensation information.

[0125] In one of the embodiments, the magnetic field separation module 502 is further used to determine the reference magnetic field amplitude and the reference magnetic field frequency based on the reference alternating current and the alternating coil parameters; generate magnetic field separation parameters based on the reference magnetic field amplitude and the reference magnetic field frequency; and separate the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information based on the magnetic field separation parameters.

[0126] Each module in the above-mentioned tunnel magnetoresistive sensor temperature compensation device based on alternating reference magnetic field can be implemented in whole or in part by software, hardware and their combination. Each of the above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the corresponding operations of each of the above modules.

[0127] In an exemplary embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be shown in FIG6. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit, and an input device. The processor, the memory, and the input / output interface are connected via a system bus, and the communication interface, the display unit, and the input device are connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner may be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a temperature compensation method for a tunnel magnetoresistance sensor based on an alternating reference magnetic field is implemented. The display unit of the computer device is used to form a visually visible picture, which may be a display screen, a projection device, or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device shell, or an external keyboard, touchpad or mouse.

[0128] Those skilled in the art will understand that the structure shown in FIG. 6 is merely a block diagram of a partial structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different arrangement of components.

[0129] In one embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above method embodiments when executing the computer program.

[0130] In one embodiment, a computer-readable storage medium is provided, storing a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0131] In one embodiment, a computer program product or computer program is provided, the computer program product or computer program includes computer instructions, the computer instructions are stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device performs the steps in the above-mentioned method embodiments.

[0132] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0133] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0134] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0135] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for temperature compensation of a tunnel magnetoresistive sensor based on an alternating reference magnetic field, characterized in that: The method comprises: Obtain the surrounding magnetic field information, AC signal amplification factor, reference alternating current, alternating coil parameters and current temperature error voltage of the tunnel magnetoresistive sensor; Separating the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters; The reference sensitivity of the tunnel magnetoresistance sensor is adjusted according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain temperature compensation information.

2. The method according to claim 1, characterized in that: The step of adjusting the reference sensitivity of the tunnel magnetoresistance sensor according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain temperature compensation information includes: Dividing the AC signal amplification factor by the reference magnetic field information to obtain the AC sensor sensitivity; Determining the sensitivity of the DC sensor according to the DC induced voltage relationship between the magnetic field information to be measured and the current temperature error voltage; The reference sensitivity is adjusted according to the difference between the sensitivity of the AC sensor and the sensitivity of the DC sensor to determine the temperature compensation information of the tunnel magnetoresistance sensor.

3. The method according to claim 2, characterized in that The step of determining the DC sensor sensitivity according to the DC induced voltage relationship between the magnetic field information to be measured and the current temperature error voltage includes: Obtaining a sensor output voltage of the tunnel magnetoresistive sensor; separating a DC output voltage from the sensor output voltage; The DC output voltage and the current temperature error voltage are adjusted according to the magnetic field information to be measured to determine the sensitivity of the DC sensor.

4. The method according to claim 3, characterized in that The step of adjusting the DC output voltage and the current temperature error voltage according to the magnetic field information to be measured to determine the sensitivity of the DC sensor includes: Using the current temperature error voltage, adjusting the DC output voltage of the sensor to obtain an adjusted DC output error; The measured magnetic field information is used to adjust the change gradient of the adjusted DC output error to determine the sensitivity of the DC sensor.

5. The method according to claim 2, characterized in that: The step of adjusting the reference sensitivity according to the difference between the sensitivity of the AC sensor and the sensitivity of the DC sensor to determine the temperature compensation information of the tunnel magnetoresistance sensor includes: Calculating the ratio between the sensitivity of the AC sensor and the sensitivity of the DC sensor to obtain a sensitivity ratio coefficient; The reference sensitivity of the tunnel magnetoresistive sensor is adjusted using the sensitivity ratio coefficient to obtain the temperature compensation information.

6. The method according to any one of claims 1 to 5, characterized in that: The step of separating the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters includes: Determining a reference magnetic field amplitude and a reference magnetic field frequency according to the reference alternating current and the alternating coil parameters; generating a magnetic field separation parameter according to the reference magnetic field amplitude and the reference magnetic field frequency; The magnetic field information to be measured and the reference magnetic field information are separated from the surrounding magnetic field information according to the magnetic field separation parameter.

7. A temperature compensation device for a tunnel magnetoresistive sensor based on an alternating reference magnetic field, characterized in that: The device comprises: An information acquisition module is used to obtain the surrounding magnetic field information of the tunnel magnetoresistive sensor, the AC signal amplification factor, the reference alternating current, the alternating coil parameters and the current temperature error voltage; A magnetic field separation module, used to separate the magnetic field information to be measured and the reference magnetic field information from the surrounding magnetic field information according to the reference alternating current and the alternating coil parameters; The compensation acquisition module is used to adjust the reference sensitivity of the tunnel magnetoresistive sensor according to the reference magnetic field information, the magnetic field information to be measured, the AC signal amplification factor and the current temperature error voltage to obtain temperature compensation information.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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