A method, device and electronic device for temperature compensation of sensor chip

Abstract

The present invention provides a method, device and electronic device for temperature compensation of a sensor chip. The method comprises applying a high-frequency magnetic field signal to the sensor chip; conditioning a first output signal output by the sensor chip and demodulating a DC signal, wherein the amplitude of the signal in the first output signal having the same frequency as the high-frequency magnetic field signal is proportional to the DC signal; and automatically adjusting the power supply voltage of the sensor chip according to the DC signal. The method ensures that the sensitivity of the sensor chip does not change significantly with temperature through closed-loop control, thereby realizing automatic temperature compensation.

Description

Technical Field

[0001] The present embodiment relates to the technical field of sensor chips, and in particular to a method, device and electronic equipment for temperature compensation of a sensor chip. Background Art

[0002] Magnetoresistive sensor chips are widely used in data storage, current measurement, displacement measurement, object movement, angle measurement and other measurement fields. For example, TMR magnetoresistive sensor chips with directly integrated magnetoresistance and piezoresistive pressure sensor chips with indirectly integrated ferromagnetic materials often have temperature-dependent sensitivity, which decreases with increasing temperature. This phenomenon is called sensitivity temperature drift.

[0003] The existing method to reduce sensitivity temperature drift is generally to configure the internal resistance of the sensor chip in the form of a Wheatstone full bridge, but experiments have shown that the temperature drift of the sensor chip sensitivity under the Wheatstone full bridge configuration is still not negligible. Sensitivity temperature drift will not only affect DC measurement but also AC measurement accuracy. Because the sensitivity temperature drift coefficient of the above-mentioned sensor chip is large and the linearity is poor, in general, the LUT (compensation lookup) method is used to compensate the sensor chip. This method has efficiency problems. Each chip needs to be tested separately to obtain the temperature drift curve and then the compensation data is written into the lookup table. For example, the chips such as Nanochip NSA5312 need to be retested in the entire temperature range when a single temperature point is poorly calibrated. Summary of the invention

[0004] The embodiments of the present invention provide a method, a device and an electronic device for temperature compensation of a sensor chip, which can realize automatic compensation of the sensitivity of the sensor chip within a large temperature range without the need to collect current temperature data in advance.

[0005] The technical solution of the present invention is:

[0006] In a first aspect, an embodiment of the present application provides a method for temperature compensation of a sensor chip, the method comprising:

[0007] applying a high-frequency magnetic field signal to the sensor chip;

[0008] Conditioning the first output signal output by the sensor chip to demodulate a DC signal; the signal amplitude of the first output signal having the same frequency as the high-frequency magnetic field signal is proportional to the DC signal;

[0009] The power supply voltage of the sensor chip is automatically adjusted according to the DC signal.

[0010] Further, the frequency of the high-frequency magnetic field signal is higher than the bandwidth frequency of the sensor chip;

[0011] The high-frequency magnetic field signal is a square wave signal;

[0012] The DC signal is linearly related to the sensitivity of the sensor chip.

[0013] Furthermore, the step of conditioning the first output signal output by the sensor chip to demodulate a DC signal includes:

[0014] filtering the signal in the first output signal that has a frequency lower than the high-frequency magnetic field signal, and outputting a second output signal;

[0015] Demodulating the second output signal to output a third output signal; the third output signal includes a DC signal and a noise signal with a frequency higher than that of the high-frequency magnetic field signal;

[0016] The third output signal is filtered to output the DC signal.

[0017] Furthermore, a signal in the first output signal having a frequency lower than the high-frequency magnetic field signal is filtered by a high-pass filter.

[0018] Furthermore, the second output signal is demodulated by a lock-in amplifier.

[0019] Furthermore, a signal in the third output signal having a frequency higher than that of the high-frequency magnetic field signal is filtered by a low-pass filter.

[0020] Furthermore, the automatically adjusting the power supply voltage of the sensor chip according to the DC signal includes:

[0021] acquiring a first reference signal;

[0022] determining whether the DC signal has the same value as the first reference signal;

[0023] If the DC signal has a value different from the first reference signal, the power supply voltage of the sensor chip is automatically adjusted.

[0024] Furthermore, determining whether the values ​​of the DC signal and the first reference signal are the same is achieved by a comparator.

[0025] Furthermore, the power supply voltage of the sensor chip is automatically adjusted, which is achieved through an integrator.

[0026] Furthermore, the sensor chip is a magnetoresistive sensor chip, which includes an AMR sensor chip, a GMR sensor chip, a TMR sensor chip, and other sensor chips with magnetoresistive effect.

[0027] In a second aspect, an embodiment of the present invention further provides a device for temperature compensation of a sensor chip, comprising:

[0028] A high-frequency magnetic field generating module, used for applying a high-frequency magnetic field signal to the sensor chip;

[0029] A conditioning module, used for demodulating the first output signal output by the sensor chip and outputting a DC signal; the signal amplitude of the first output signal having the same frequency as the high-frequency magnetic field signal is proportional to the DC signal;

[0030] An adjustment module is used to automatically adjust the supply voltage of the sensor chip according to the DC signal.

[0031] Furthermore, the conditioning module comprises:

[0032] a first filtering unit, electrically connected to the sensor chip, for filtering a signal in the first output signal that has a frequency lower than the high-frequency magnetic field signal, and outputting a second output signal;

[0033] a phase-locked amplifier unit, electrically connected to the high-frequency magnetic field generating module and the first filtering unit, respectively, for demodulating the second output signal and outputting a third output signal; the third output signal includes a DC signal and a noise signal, and the frequency of the noise signal is higher than the frequency of the high-frequency magnetic field signal;

[0034] The second filtering unit is electrically connected to the phase-locked amplification unit and the conditioning module respectively, and is used to filter the noise signal in the third output signal and output the DC signal.

[0035] Furthermore, the adjustment module includes:

[0036] A reference unit, configured to obtain a first reference signal;

[0037] a comparison unit, electrically connected to the reference unit and the conditioning module, and configured to determine whether the values ​​of the DC signal and the first reference signal are equal;

[0038] The adjustment unit is electrically connected to the comparison unit and the sensor chip respectively, and is used to automatically adjust the power supply voltage of the sensor chip when the values ​​of the DC signal and the first reference signal are different.

[0039] Furthermore, the comparison unit includes a comparator, and the adjustment unit includes an integrator; the positive phase end of the comparator is connected to the output end of the reference unit, and the reference unit provides a first reference signal, and the negative phase end of the comparator is connected to the output end of the conditioning unit, and the comparator is used to compare the DC signal output by the conditioning unit with the first reference signal, and output the difference after comparison; the input end of the integrator is connected to the output end of the comparator, and the output end of the integrator is connected to the power supply end of the sensor chip, and the integrator is used to integrate the difference after comparing the DC signal output by the comparator with the first reference signal, and input it to the power supply end of the sensor chip to automatically adjust the power supply voltage of the sensor chip.

[0040] Furthermore, the high-frequency magnetic field generating module comprises:

[0041] A high-frequency electrical signal generating unit, used for generating a high-frequency electrical signal;

[0042] The excitation magnetic field generating unit is electrically connected to the high-frequency electrical signal generating unit and is used to apply a high-frequency magnetic field signal to the sensor chip; the direction of the high-frequency magnetic field signal is parallel to at least part of the sensitive direction of the sensor chip.

[0043] In a third aspect, an embodiment of the present invention further provides an electronic device, including a sensor chip and a device for temperature compensation of the sensor chip; the device is the above-mentioned device, or is manufactured by the above-mentioned method.

[0044] The beneficial effects brought about by the technical solutions provided in some embodiments of the present application include at least: detecting and extracting the output of the corresponding sensor chip by externally applying a high-frequency magnetic field signal with a frequency several times higher than the frequency of the measured current, demodulating the first output signal output by the sensor chip, and outputting a DC signal; automatically adjusting the power supply voltage of the sensor chip according to the DC signal; the method of temperature compensating the sensor chip automatically adjusts its power supply voltage when the temperature changes, so that the sensitivity of the sensor chip is automatically compensated with the temperature, and there is no need to collect current temperature data in advance. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0046] Figure 1 is a flow chart of a method according to an embodiment of the present invention;

[0047] Figure 2is a circuit structure block diagram of an embodiment of the present invention;

[0048] Figure 3 Schematic diagram of the layout structure of the excitation magnetic field generating circuit according to an embodiment of the present invention.

[0049] The specific implementation modes of the present invention are further described in detail below with reference to the accompanying drawings. DETAILED DESCRIPTION

[0050] The present invention is described in detail below in conjunction with the accompanying drawings. When describing the embodiments of the present invention in detail, for the convenience of explanation, the drawings showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. It should be noted that the drawings are simplified and all use non-precise scales, which are only used to facilitate and clearly assist in explaining the purpose of the embodiments of the present invention.

[0051] It should be noted that the connection mentioned in this application can be a direct connection or an indirect connection. The sensor chip mentioned in this application can be a sensor chip whose sensitivity is linearly related to the power supply voltage, and is particularly suitable for sensor chips whose sensitivity is linearly related to the power supply voltage, such as a magnetoresistive sensor chip with a magnetoresistive directly integrated inside the chip or a magnetoresistive sensor chip with a ferromagnetic material indirectly integrated outside the chip. In addition, as a supplementary explanation, the unit of sensor chip sensitivity is mV / V / Oe. In actual use, the sensitivity S can be controlled by changing the power supply voltage. T , the sensitivity can be expressed by the formula S T =pV s S To (1+a(T-T0) is obtained, where p is the amplification factor; Vs is the supply voltage. In addition, the present application is applicable to the field of sensor chip measurement of current below 10kHz.

[0052] The sensor chip is described below by taking a TMR magnetoresistive sensor chip with directly integrated magnetoresistive as an example, and is referred to as a sensor chip for short.

[0053] The basic principle of the technical solution of the embodiment of the present application is to detect and extract the output of the corresponding sensor chip by externally applying a high-frequency magnetic field signal with a frequency several times higher than the frequency of the measured current, compare it with the external magnetic field, and extract the sensitivity information of the sensor chip at different temperature points in real time. By comparing the sensitivity information with the reference level, the difference is obtained, and the power supply voltage of the magnetic sensor chip is automatically adjusted when the difference occurs, so that the sensitivity of the sensor chip at different temperature points is automatically compensated to near a constant value. The overall external effect achieved is that the sensitivity of the sensor chip does not change with temperature, and automatic temperature compensation is achieved.

[0054] See also Figure 1, a method for temperature compensation of a sensor chip, the method comprising the steps of:

[0055] S1, applying a high-frequency magnetic field signal to the sensor chip;

[0056] In this step, a high-frequency electrical signal higher than the frequency of the electrical signal to be measured by the sensor chip is generated by a high-frequency signal generator. After the high-frequency electrical signal is generated, the high-frequency electrical signal is induced by the exciting magnetic field generating circuit, and a high-frequency magnetic field signal having a partial component parallel to the sensitive direction of the sensor chip is generated. The partial component here is the main component in the generated high-frequency magnetic field signal. The magnetic resistance in or outside the sensor chip senses the high-frequency magnetic field signal, and then the current changes. Ideally, the frequency of the high-frequency electrical signal generated by the high-frequency signal generator, that is, the frequency of the high-frequency magnetic field signal, should be several times higher than the frequency of the measured current. Generally, it is also required to be more than twice the bandwidth of the sensor chip. Using high-frequency external excitation, the measurement working circuit and the compensation circuit working loop can be set to two different working frequencies respectively, so that the two do not interfere with each other. In this embodiment, the high-frequency electrical signal is a square wave signal, and a square wave voltage with a constant amplitude between 25% and 75% duty cycle is selected, and the duty cycle is preferably 50%. In this way, a stable DC signal can be obtained, and then this high-frequency electrical signal acts on the excitation magnetic field generating circuit. The excitation magnetic field generating circuit can be based on the routing on the PCB board, wherein the PCB routing can be laid out according to actual conditions. However, in this embodiment, it is preferred to ensure that at least the main component of the magnetic field generated by the circuit is parallel to the sensitive direction of the sensor chip.

[0057] S2, conditioning the first output signal output by the sensor chip and demodulating a DC signal, wherein the signal amplitude of the first output signal having the same frequency as the high-frequency magnetic field signal is proportional to the DC signal, and the DC signal is linearly correlated with the sensitivity of the sensor chip.

[0058] In this step, the first output signal output by the sensor chip is conditioned and demodulated into a DC signal in the following manner, including:

[0059] filtering the signal in the first output signal that has a frequency lower than the high-frequency magnetic field signal, and outputting a second output signal;

[0060] Demodulating the second output signal to output a third output signal; the third output signal includes a DC signal and a noise signal with a frequency higher than that of the high-frequency magnetic field signal;

[0061] The third output signal is filtered to output the DC signal.

[0062] Among them, it is necessary to first filter out the low-frequency component in the first output signal that is lower than the frequency of the high-frequency electrical signal, and then modulate the high-frequency signal with the same frequency as the high-frequency electrical signal into a DC component output; the DC component, that is, the DC signal, wherein the DC component is linearly related to the sensitivity of the sensor chip. It is also necessary to explain that the phase-locked amplifier has high accuracy and high equivalent Q value for measuring specific frequency signals. The use of the phase-locked amplifier can eliminate interference from other frequencies, and the reference signal used by the phase-locked amplifier for frequency locking is the same source as the high-frequency magnetic field signal acting on the sensor chip, that is, the same frequency. After the above steps, a DC signal linearly related to the sensitivity of the sensor chip can be obtained.

[0063] S3, automatically adjusting the power supply voltage of the sensor chip according to the DC signal.

[0064] In this step, the method for automatically adjusting the power supply voltage of the sensor chip according to the DC signal includes:

[0065] acquiring a first reference signal;

[0066] determining whether the DC signal has the same value as the first reference signal;

[0067] If the DC signal has a value different from the first reference signal, the power supply voltage of the sensor chip is automatically adjusted.

[0068] In this step, when determining whether the values ​​of the DC signal and the first reference signal are the same, it is achieved through a comparator, the positive phase end of the comparator is connected to a reference signal generating device, the reference signal generating device provides a reference voltage source for the comparator, and the reference voltage source provides a first reference signal, that is, a first reference level, and the negative phase end of the comparator inputs the above-mentioned DC signal.

[0069] In some embodiments, the DC signal has a different value from the first reference signal, and the automatic adjustment of the power supply voltage of the sensor chip can be achieved through an integrator. The input end of the integrator is connected to the output end of the comparator circuit, and the output end of the integrator is connected to the power supply end of the sensor chip. The integrator integrates the difference between the DC signal and the first reference signal, and inputs the difference to the power supply end of the sensor chip, thereby automatically adjusting the power supply voltage of the sensor chip.

[0070] This embodiment also provides a device for temperature compensation of a sensor chip, comprising:

[0071] A high-frequency magnetic field generating module, used for applying a high-frequency magnetic field signal to the sensor chip;

[0072] A conditioning module, used for demodulating the first output signal output by the sensor chip and outputting a DC signal; the signal amplitude of the first output signal having the same frequency as the high-frequency magnetic field signal is proportional to the DC signal;

[0073] An adjustment module is used to automatically adjust the supply voltage of the sensor chip according to the DC signal.

[0074] In some embodiments, the conditioning module comprises:

[0075] a first filtering unit, electrically connected to the sensor chip, for filtering a signal in the first output signal that has a frequency lower than the high-frequency magnetic field signal, and outputting a second output signal;

[0076] a phase-locked amplifier unit, electrically connected to the high-frequency magnetic field generating module and the first filtering unit, respectively, for demodulating the second output signal and outputting a third output signal; the third output signal includes a DC signal and a noise signal, and the frequency of the noise signal is higher than the frequency of the high-frequency magnetic field signal;

[0077] The second filtering unit is electrically connected to the phase-locked amplification unit and the conditioning module respectively, and is used to filter the noise signal in the third output signal and output the DC signal.

[0078] In some embodiments, the adjustment module includes:

[0079] A reference unit, configured to obtain a first reference signal;

[0080] a comparison unit, electrically connected to the first reference unit and the conditioning module, and configured to determine whether the values ​​of the DC signal and the first reference signal are equal;

[0081] The adjustment unit is electrically connected to the comparison unit and the sensor chip respectively, and is used to automatically adjust the power supply voltage of the sensor chip when the values ​​of the DC signal and the first reference signal are different.

[0082] In some embodiments, Figure 2 As shown, the above device can be realized by the following circuit:

[0083] The high-frequency magnetic field generating module includes a high-frequency electric signal generating unit and an excitation magnetic field generating unit. The high-frequency electric signal generating unit, i.e., the high-frequency signal generator, generates a high-frequency electric signal higher than the frequency of the electric signal to be measured by the sensor chip. After the high-frequency electric signal is generated, the high-frequency electric signal is sensed by the excitation magnetic field generating unit, i.e., the excitation magnetic field generating circuit, and a high-frequency magnetic field signal having a partial component parallel to the sensitive direction of the sensor chip is generated. The sensor chip in the sensor chip or the sensor chip bound outside the ordinary other types of sensor chips senses the high-frequency magnetic field signal, and then the current changes. The partial component here is preferably the main component in the direction of the generated magnetic field. In an ideal state, the frequency of the high-frequency electric signal generated by the high-frequency signal generator should be several times higher than the frequency of the measured current. In general, it is also required to be higher than twice the bandwidth of the sensor chip. Using high-frequency external excitation, the measurement working circuit and the compensation circuit working loop can be set to two different working frequencies respectively, so that the two do not interfere with each other. In this embodiment, the high-frequency electric signal is a square wave signal, and a square wave voltage with a constant amplitude between 25% and 75% duty cycle is selected, and the duty cycle is preferably 50%. In this way, a stable DC signal can be obtained, and then this high-frequency electrical signal acts on the excitation magnetic field generating circuit. The excitation magnetic field generating circuit can be based on the routing on the PCB board, wherein the PCB routing can be laid out according to actual conditions. However, in this embodiment, it is preferred to ensure that at least the main component of the magnetic field generated by the circuit is parallel to the sensitive direction of the sensor chip. In this embodiment, Figure 3 As shown, it is a schematic diagram of the layout structure of an excitation magnetic field generating circuit, a first PCB board 102 and a second PCB board 103, the first PCB board 102 and the second PCB board 103 are used for routing, the routing is connected to the high-frequency signal generator, and can be arranged in parallel, the precision resistor 101 can be arranged on the first PCB board 102, and connected to the circuit on the first PCB board 102, the sensor chip 104 is installed between the first PCB board 102 and the second PCB board 103, the external square wave voltage signal is converted into current through the precision resistor 101, and the current forms a loop through the first PCB board 102 and the second PCB board 103, and an external magnetic field in the same direction as the sensitive direction of the sensor chip 104 is generated at the location of the sensor chip 104. Then, an electrical signal after the sensor chip 104 undergoes the above-mentioned excitation operation is obtained, and the electrical signal is the first output signal described below.

[0084] like Figure 3As shown, the first filtering unit adopts a high-pass filter HPF, the phase-locked amplification unit includes a phase-locked amplifier, and the second filtering unit adopts a low-pass filter LPF, wherein the first reference signal can be the value of a DC signal measured when the sensor chip works in the above working environment and at a normal working temperature; the comparison unit includes a comparator, and the adjustment unit includes an integrator. The input end of the high-pass filter HPF is connected to the output end of the sensor chip, the output end of the high-pass filter HPF is connected to the input end of the phase-locked amplifier, the signal reference end of the phase-locked amplifier is connected to the high-frequency signal generator, and the high-frequency signal generator provides the second reference signal to the phase-locked amplifier, the output end of the phase-locked amplifier is connected to the input end of the low-pass filter LPF, the output end of the low-pass filter LPF is connected to the negative phase input end of the comparator, the positive phase input end of the comparator is connected to the reference unit, and the reference unit provides the first reference signal.

[0085] In this embodiment, the comparator is used to compare the DC signal output by the conditioning unit with the first reference signal and output the difference after comparison; the integrator is used to integrate the difference after comparing the DC signal output by the comparator with the first reference signal, and input it to the power supply end of the sensor chip to adjust the power supply voltage of the sensor chip.

[0086] The device of this embodiment works as follows:

[0087] When powered on for the first time, due to the existence of the integrator, when the device is not working in a stable state, the integrator output is at the maximum value, that is, the sensor chip power supply voltage is at the maximum value, and the sensitivity of the sensor chip is at the maximum;

[0088] When the sensitivity of the sensor chip is greater than the expected value, the DC signal output by the lock-in amplifier is greater than the first reference signal and the first reference level, the comparator output voltage is negative, and the voltage output by the integrator is reduced after integration by the integrator, thereby reducing the power supply voltage of the sensor chip and reducing the sensitivity;

[0089] When the sensitivity of the sensor chip is less than the expected value, the DC signal output by the phase-locked amplifier is less than the first reference signal, the comparator output voltage is positive, and after integration by the integrator, the voltage output by the integrator is increased, thereby raising the supply voltage of the sensor chip and improving the sensitivity.

[0090] In summary, the detection signal output by the sensor chip is compared with the first reference signal through the filter output to form a difference, and then delayed by the integrator to form the power supply voltage of the sensor chip. Through closed-loop control, or using the closed loop and making the closed loop work to a state of zero static error system, the compensation accuracy can be made higher. Ideally, the zero drift effect can be achieved. Therefore, the sensitivity of the sensor chip can be guaranteed to be constant, that is, the value of the phase-locked amplifier output after passing through the low-pass filter LPF can be guaranteed to be constant.

[0091] In addition, when the first reference signal is adjusted, the adjustment amount can be directly reflected to the power supply of the sensor chip after passing through the comparator and the integrator, and the sensitivity of the sensor chip is strictly linearly correlated with the first reference signal.

[0092] It should also be noted that when the sensor chip of the above embodiment is used for measurement, the low-frequency signal does not affect the circuit operation after being attenuated by the HPF, and the signal with a frequency higher than the high-frequency magnetic field signal can be eliminated through the rear phase-locked amplifier, low-pass filter LPF and integrator.

[0093] It should be noted that a frequency close to the square wave signal in the above embodiment may affect the circuit operating accuracy, so this solution is suitable for current measurement with a frequency lower than the square wave signal.

[0094] The above embodiment obtains the first output signal of the sensor chip after high-frequency excitation, modulates the first output signal, and modulates the signal in the first output signal that is at the same frequency as the high-frequency signal generator into a DC signal output, wherein the DC signal is linearly related to the sensitivity of the sensor chip, and then compares the DC signal as a negative phase with the first reference signal as a positive phase, and outputs the difference after comparison, and finally integrates the difference after comparison and inputs it to the power supply end of the sensor chip, automatically adjusting the power supply voltage of the sensor chip, thereby realizing continuous compensation of the sensitivity temperature drift of the sensor chip in the full temperature range, and realizing the elimination of the need for temperature acquisition.

[0095] In summary, the above embodiment can achieve the compensation of temperature drift of sensor chip sensitivity without the need to know the external temperature or to ensure uniform temperature of the sensor chip without a temperature sensor chip, and does not affect the measurement effect of the sensor chip itself. This method also achieves the technical effects of setting the sensitivity of the compensated sensor chip through the first reference signal, eliminating the delay and lag of the temperature conduction process, and providing fast and accurate response.

[0096] This embodiment also provides an electronic device, including a sensor chip and a device for temperature compensation of the sensor chip; the device is the above-mentioned device of this embodiment, or is made according to the above-mentioned method. The sensor chip in the electronic device and the device for temperature compensation of the sensor chip are discussed above, and will not be repeated here.

[0097] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for temperature compensation of a sensor chip, characterized in that: The method comprises: Applying a high-frequency magnetic field signal to the sensor chip; wherein the sensor chip is a magnetoresistive sensor chip, and its sensitivity is linearly related to the supply voltage; Conditioning the first output signal output by the sensor chip and demodulating a DC signal; the signal amplitude of the first output signal having the same frequency as the high-frequency magnetic field signal is proportional to the DC signal; the demodulating the DC signal specifically includes: filtering the signal of the first output signal having a frequency lower than the high-frequency magnetic field signal and outputting a second output signal; demodulating the second output signal and outputting a third output signal, wherein the third output signal includes a DC signal and a noise signal having a frequency higher than the high-frequency magnetic field signal; filtering the third output signal and outputting the DC signal; The power supply voltage of the sensor chip is automatically adjusted according to the DC signal; the automatic adjustment specifically includes: obtaining a first reference signal; comparing the DC signal with the first reference signal, and outputting the difference after comparison; integrating the difference and inputting it to the power supply terminal of the sensor chip, and automatically adjusting the power supply voltage of the sensor chip.

2. The method according to claim 1, characterized in that The frequency of the high-frequency magnetic field signal is higher than the bandwidth frequency of the sensor chip; The high-frequency magnetic field signal is a square wave signal; The DC signal is linearly related to the sensitivity of the sensor chip.

3. A device for temperature compensation of a sensor chip, characterized in that: include A high-frequency magnetic field generating module, used for applying a high-frequency magnetic field signal to the sensor chip; wherein the sensor chip is a magnetoresistive sensor chip, and its sensitivity is linearly related to the supply voltage; A conditioning module, used to demodulate the first output signal output by the sensor chip and output a DC signal; the signal amplitude of the first output signal having the same frequency as the high-frequency magnetic field signal is proportional to the DC signal; the conditioning module includes: a first filtering unit, electrically connected to the sensor chip, used to filter the signal in the first output signal that is lower than the frequency of the high-frequency magnetic field signal and output a second output signal; a phase-locked amplifier unit, electrically connected to the high-frequency magnetic field generating module and the first filtering unit, respectively, used to demodulate the second output signal and output a third output signal; the third output signal includes a DC signal and a noise signal, and the frequency of the noise signal is higher than the frequency of the high-frequency magnetic field signal; a second filtering unit, electrically connected to the phase-locked amplifier unit and the conditioning module, respectively, used to filter the noise signal in the third output signal and output the DC signal; an adjustment module, for automatically adjusting the power supply voltage of the sensor chip according to the DC signal; the adjustment module comprises: a reference unit, for obtaining a first reference signal; a comparison unit, electrically connected to the reference unit and the conditioning module, for determining whether the DC signal and the first reference signal have the same value; an adjustment unit, electrically connected to the comparison unit and the sensor chip, respectively, for automatically adjusting the power supply voltage of the sensor chip when the DC signal and the first reference signal have different values; the comparison unit comprises a comparator, and the adjustment unit comprises an integrator; the positive phase end of the comparator is connected to the output end of the reference unit, the first reference signal is provided by the reference unit, the negative phase end of the comparator is connected to the output end of the conditioning unit, the comparator is used to compare the DC signal output by the conditioning unit with the first reference signal, and output the difference after comparison; the input end of the integrator is connected to the output end of the comparator, the output end of the integrator is connected to the power supply end of the sensor chip, the integrator is used to integrate the difference after comparing the DC signal output by the comparator with the first reference signal, and input it to the power supply end of the sensor chip, so as to automatically adjust the power supply voltage of the sensor chip.

4. The device according to claim 3, characterized in that The high-frequency magnetic field generating module comprises: A high-frequency electrical signal generating unit, used for generating a high-frequency electrical signal; The excitation magnetic field generating unit is electrically connected to the high-frequency electrical signal generating unit and is used to apply a high-frequency magnetic field signal to the sensor chip; the direction of the high-frequency magnetic field signal is parallel to at least part of the sensitive direction of the sensor chip.

5. An electronic device, characterized in that: A sensor chip and a device for temperature compensation of the sensor chip; The device is the device according to claim 3 or 4, or is made according to the method according to claim 1 or 2.

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