Resonant multi-parameter sensor and device

Abstract

The invention belongs to the field of micro electro mechanical system sensors, and provides a resonant multi-parameter sensor and device, which comprises a plurality of resonant probes and a plurality of detection circuits, the resonant probes are respectively connected with the corresponding detection circuits; the resonant probe comprises a resonant beam structure for detecting different environment parameters; and the detection circuit is used for performing multi-path orthogonal demodulation on the current signal output by the resonant probe to obtain resonant frequency, and outputting a parameter measurement result based on a corresponding relation between the resonant frequency and an environment parameter. The invention provides a resonant sensor capable of realizing synchronous acquisition and reading of multiple parameters.

Description

Technical Field

[0001] The present invention belongs to the field of micro-electromechanical system sensors, and in particular relates to a resonant multi-parameter sensor and a device. Background Art

[0002] The development of precision measuring instruments determines the progress in the fields of frontier research in physics, geological exploration, and ocean observation. Every breakthrough in the accuracy of precision measuring instruments for scientific research and exploration is expected to produce new discoveries in the verification of physical laws, planetary physics research, and earth resource exploration. Environmental changes such as temperature, magnetic field, vibration, and air pressure in precision measuring instruments will bring additional noise to precision measuring instruments. For precision measuring instruments in complex environmental conditions such as the field, seabed, aviation, and aerospace, it is necessary to adopt multi-level passive shielding and high-precision active control to reduce the noise impact caused by the above multiple environmental changes. Among them, the high-precision active control part is composed of corresponding sensors, controllers, and actuators. The sensor unit can realize the monitoring of environmental parameters, and its resolution level will affect the accuracy level of the active control part. It can be seen that in order to achieve high-precision measurement of precision measuring instruments under complex working conditions, the sensor unit in the high-precision active control part needs to realize multi-environmental parameter monitoring and higher resolution measurement.

[0003] Existing high-resolution multi-parameter sensor technologies are mainly divided into optical, mechanical resonant, and multi-principle integrated types. Although optical multi-parameter sensors such as fiber gratings and optical resonant cavities can achieve temperature, strain, and other measurements through different packaging forms, their system complexity is high and their adaptability to harsh environments is limited; mechanical resonant sensors such as quartz crystal resonators and silicon microresonators can achieve high-resolution dual-parameter measurements, but their multi-parameter collaborative sensitivity is insufficient and cannot meet the needs of environmental monitoring under complex working conditions. In addition, multi-principle integrated sensors are difficult to achieve high integration and miniaturization due to the complex demodulation method. Summary of the invention

[0004] In order to overcome the defect of insufficient multi-parameter cooperative sensitivity of the resonant sensor described in the above-mentioned prior art, the present invention provides a resonant multi-parameter sensor and a device.

[0005] In order to achieve the above technical effects, the technical solution of the present invention is as follows:

[0006] The present invention provides a resonant multi-parameter sensor, comprising: a plurality of resonant probes and a plurality of detection circuits; the resonant probes are respectively connected to corresponding detection circuits;

[0007] The resonant probe comprises a resonant beam structure for detecting different environmental parameters;

[0008] The detection circuit is used to perform multi-channel orthogonal demodulation on the current signal output by the resonant probe to obtain the resonant frequency, and output the parameter measurement result based on the corresponding relationship between the resonant frequency and the environmental parameter.

[0009] The present invention also provides a resonant multi-parameter detection device, comprising at least one resonant multi-parameter sensor.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] The present invention proposes a resonant multi-parameter sensor and device, which realizes the measurement of multi-parameters integrated in a single chip through different resonant probes composed of different resonant beam structures, meeting the needs of multi-parameter measurement in complex working conditions and environments; and adopts a multi-channel orthogonal demodulation method to realize the demodulation and synchronous readout of the amplitude and frequency of the multi-resonant sensor on a single chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is the architecture diagram of the resonant multi-parameter sensor.

[0013] Figure 2 This is the combined structure diagram of the resonant multi-parameter probe.

[0014] Figure 3 This is the structural diagram of the resonant temperature sensor probe.

[0015] Figure 4 This is a structural diagram of a resonant magnetic field probe.

[0016] Figure 5 This is the structural diagram of the resonant vibration probe.

[0017] Figure 6 FIG. 4 is a circuit structure diagram of the detection circuit. DETAILED DESCRIPTION

[0018] The accompanying drawings are only used for illustrative purposes and are not to be construed as limiting the present invention;

[0019] It is understandable to those skilled in the art that some well-known descriptions may be omitted in the drawings.

[0020] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0021] Example 1

[0022] This embodiment proposes a resonant multi-parameter sensor, such as Figure 1 , which is a structural diagram of the resonant multi-parameter sensor of this embodiment.

[0023] The resonant multi-parameter sensor proposed in this embodiment includes: a plurality of resonant probes 1 and a plurality of detection circuits 2; the resonant probes 1 are respectively connected to corresponding detection circuits 2;

[0024] The resonant probe 1 includes a resonant beam structure for detecting different environmental parameters;

[0025] The detection circuit 2 is used to perform multi-channel orthogonal demodulation on the current signal output by the resonant probe 1 to obtain the resonant frequency, and output the parameter measurement result based on the corresponding relationship between the resonant frequency and the environmental parameter.

[0026] In this embodiment, the current signals output by different resonant probes 1 composed of different resonant beam structures are subjected to multi-channel orthogonal demodulation to obtain the resonant frequency, and the parameter measurement results are obtained through the correspondence between the pre-calibrated resonant frequency and the parameter. The present invention not only meets the demand for high-precision measurement of multiple parameters under complex working conditions and environments, but also can realize the synchronous demodulation and reading of the amplitude and frequency of multiple resonant sensors on a single chip, and has significant advantages in high precision, low power consumption and miniaturization. In addition, through the orthogonal demodulation technology, signal coupling and external noise interference are effectively avoided between the probes to ensure the accuracy of the data.

[0027] In an optional embodiment, the resonant probe 11 includes: a resonant temperature sensing probe 3 , a resonant magnetic field probe 4 and a resonant vibration probe 5 .

[0028] For example, Figure 2 , which is a combined structure diagram of the resonant multi-parameter probe 1 of this embodiment; it includes four resonant temperature sensing probes 3, two first resonant magnetic field probes 4 and a resonant vibration probe 5.

[0029] In this embodiment, different types of resonant probes 1 can be used to simultaneously monitor multiple environmental parameters such as temperature, magnetic field and vibration, thereby meeting the needs of multi-dimensional environmental monitoring under complex working conditions.

[0030] In an optional embodiment, the resonant temperature sensing probe 3 includes a DC bias electrode 301, a driving electrode 302, a sensing electrode 303 and a temperature-sensitive resonant beam 305 that changes the resonant frequency based on temperature; one end of the temperature-sensitive resonant beam is connected to the DC bias electrode, and the driving electrode and the sensing electrode are placed opposite to each other on both sides of the temperature-sensitive resonant beam; the driving electrode receives an AC voltage signal output by a detection circuit, the AC voltage causes the temperature-sensitive resonant beam to start resonant motion, and the sensing electrode senses the vibration signal of the temperature-sensitive resonant beam and outputs it to the detection circuit.

[0031] like Figure 3 As shown, it is a structural diagram of the resonant temperature sensor probe 3.

[0032] Further optionally, the temperature-sensitive resonant beam 305 is fixed by the resonant beam anchor point 304 , and the DC bias electrode 301 , the driving electrode 302 , the sensing electrode 303 , the resonant beam anchor point 304 , and the resonant beam 305 are all integratedly processed by MEMS processing technology.

[0033] In this embodiment, the temperature sensitive resonant beam 305 is sensitive to temperature and the measurement principle is as follows:

[0034] A DC voltage is applied to the DC bias electrode 301, so that the DC bias electrode 301, the temperature-sensitive resonant beam 305, and the resonant beam anchor point 304 have a DC voltage bias, and the driving electrode 302 receives the AC voltage signal at the driving input resonant frequency of the detection circuit 2, so that the temperature-sensitive resonant beam 305 starts resonant motion, and the vibration signal of the temperature-sensitive resonant beam 305 is sensed by the sensing electrode 303. As an exemplary illustration, the material of the temperature-sensitive resonant beam 305 is single crystal silicon, and the Young's modulus E(T) of single crystal silicon will change with the temperature T. Taking a double-end clamped beam as an example, its resonant frequency f(T) can be expressed as:

[0035]

[0036] Wherein, f(T) is the resonant frequency that varies with temperature, E(T) is the Young's modulus that varies with temperature, I is the moment of inertia of the temperature-sensitive resonant beam 305, L is the length of the temperature-sensitive resonant beam 305, A is the cross-sectional area of ​​the temperature-sensitive resonant beam 305, ρ is the density of silicon, the material of the temperature-sensitive resonant beam 305, and β is the vibration modal coefficient.

[0037] Under different doping conditions, the TCE value of silicon material is about -60ppm / ℃~-100ppm / ℃. When the resonator system presents negative temperature characteristics, the TCF coefficient is negative. The temperature increase will reduce the resonant frequency of the resonator, and when the temperature decreases, the resonant frequency will increase. The temperature-resonant frequency sensitivity is obtained by calibrating the temperature sensor.

[0038] In this embodiment, the temperature measurement method is based on the high sensitivity relationship between the resonant frequency and temperature, and can provide accurate frequency response under slight temperature changes. When the temperature rises, the resonant frequency will decrease, and when the temperature decreases, the frequency will increase. The temperature-frequency sensitivity is obtained by calibrating the temperature sensor, so that the temperature can be measured through the resonant frequency. Due to its working principle based on resonance, the system has strong resistance to external interference and can work stably in complex environments. It is suitable for application fields with high requirements for high precision and long-term stability, such as aerospace, geological exploration and deep-sea exploration.

[0039] In an optional embodiment, the resonant magnetic field probe includes a DC bias electrode, a driving electrode, a sensing electrode, a Lorentz force generating beam and a first resonant beam; both ends of the first resonant beam are connected to the Lorentz force generating beam, the Lorentz force generating beam is connected to the DC bias electrode, and the driving electrode and the sensing electrode are placed opposite to each other on both sides of the first resonant beam; the driving electrode receives the AC voltage signal output by the detection circuit and outputs it to the Lorentz force generating beam, the Lorentz force generated in the Lorentz force generating beam generates stress between the Lorentz force generating beam and the first resonant beam, and the sensing electrode senses the vibration signal of the first resonant beam and outputs it to the detection circuit.

[0040] like Figure 4 As shown, it is the structural diagram of the resonant magnetic field probe.

[0041] Further optionally, the DC bias electrode includes a first DC bias electrode 401 , a second DC bias electrode 402 , a third DC bias electrode 403 , and a fourth DC bias electrode 404 ; and the Lorentz force generating beam includes a first Lorentz force generating beam 407 and a second Lorentz force generating beam 408 .

[0042] The first DC bias electrode 401, the second DC bias electrode 402, the third DC bias electrode 403, the fourth DC bias electrode 404, the driving electrode 405, the sensing electrode 406, the first Lorentz force generating beam 407, the second Lorentz force generating beam 408, and the first resonant beam 409 are all integratedly processed by MEMS processing technology.

[0043] In this embodiment, the first resonant beam is sensitive to and measures the magnetic field in accordance with the following principles:

[0044] A DC bias voltage is applied to the first DC bias electrode 401, and the second DC bias electrode 402 is grounded, so that a current is generated in the first Lorentz force generating beam 407 to be sensitive to the magnetic field, and an axial tension or pressure is generated on the first resonant beam 409. This tension or pressure will change the resonant frequency of the first resonant beam 409. Taking a double-ended fixed tuning fork as an example, it can be expressed as:

[0045]

[0046] Wherein, f0 is the resonant frequency of the first resonant beam 409, F is the pressure or tension between the Lorentz force generating beam and the first resonant beam, L is the length of the first resonant beam, t is the thickness of the first resonant beam, w is the width of the first resonant beam, and E is the Young's modulus of the material of the first resonant beam. The AC voltage signal at the resonant frequency is input by the driving electrode 405 to make the first resonant beam 409 start resonant motion, and the vibration signal of the first resonant beam 409 is sensed by the sensing electrode 406. The magnetic field-resonant frequency sensitivity of the resonant frequency of the first resonant beam is obtained by calibration, and the magnetic field sensing can be realized by reading the resonant frequency of the first resonant beam 409. As for the influence of temperature on the resonant frequency, the frequency output of the temperature sensitive probe can be differentially modulated with the magnetic field sensitive probe to reduce the influence of temperature on the frequency output of the magnetic field sensitive probe.

[0047] In this embodiment, a DC voltage is applied by using a DC bias electrode, and the generated Lorentz force exerts tension or pressure on the first resonant beam through the Lorentz force generating beam, thereby changing its resonant frequency. The magnetic field sensing method based on the change of resonant frequency has extremely high sensitivity and accuracy, and can provide accurate frequency response under slight magnetic field changes, which is suitable for high-precision magnetic field measurement needs.

[0048] In an optional embodiment, the resonant vibration probe includes a DC bias electrode, a driving electrode, a sensing electrode, a mass block and a second resonant beam; one end of the second resonant beam is connected to the DC bias electrode, the driving electrode and the sensing electrode are placed opposite to each other on both sides of the second resonant beam, and the mass block is connected to the other end of the second resonant beam; the driving electrode receives an AC voltage signal output by a detection circuit, the AC voltage causes the second resonant beam to start resonant motion, the mass block changes the stress between it and the second resonant beam based on vibration, and the sensing electrode senses the vibration signal of the second resonant beam and outputs it to the detection circuit.

[0049] like Figure 5 As shown, this is the structural diagram of the resonant vibration probe.

[0050] Further optionally, the resonant vibration probe 5 includes an upper DC bias electrode 501, an upper drive electrode 502, an upper sensing electrode 503, an upper resonant beam 504, a lower DC bias electrode 505, a lower drive electrode 506, a lower sensing electrode 507, a lower resonant beam 508, a test mass anchor point 509, and a mass block 5010, and all are integratedly processed by MEMS processing technology.

[0051] The upper driving electrode 502 and the upper sensing electrode 503 form a capacitor with the upper resonant beam 504, and the lower driving electrode 506 and the lower sensing electrode 507 form a capacitor with the lower resonant beam 508. The sensitivity and measurement principle of the resonant beam to the magnetic field are as follows:

[0052] A DC bias voltage is applied to the upper DC bias electrode 501, so that the upper DC bias electrode 501, the upper driving electrode 502, the upper sensing electrode 503, the upper resonant beam 504, the lower DC bias electrode 505, the lower resonant beam 508, the inspection mass anchor point 509, and the inspection mass 5010 generate a DC voltage bias, and the upper driving electrode 502 and the lower driving electrode 506 input an AC voltage signal at the resonant frequency, so that the upper resonant beam 504 and the lower resonant beam 508 start resonant motion, and the vibration signals of the upper resonant beam 504 and the lower resonant beam 508 are sensed by the upper sensing electrode 503 and the lower sensing electrode 507. The mass block 5010 will be affected by the vibration, and a tensile force or a pressure will be generated on the upper resonant beam 504 and the lower resonant beam 508, and this tensile force or a pressure will change the resonant frequency of the upper resonant beam 504 and the lower resonant beam 508. The vibration-resonance frequency sensitivity of the upper resonant beam 504 and the lower resonant beam 508 is obtained by calibration, and magnetic field sensing can be realized by reading the resonant frequency of the upper resonant beam 504 and the lower resonant beam 508. As for the influence of temperature on the resonant frequency, the frequency output of the temperature sensitive probe can be differentially measured with the vibration sensitive probe to reduce the influence of temperature on the frequency output of the magnetic field sensitive probe.

[0053] In this embodiment, the frequency change caused by the vibration can be sensed with high precision through the vibration response of the upper resonant beam and the lower resonant beam. When the mass block is affected by the vibration, the tension or pressure generated causes the resonant frequency of the upper and lower resonant beams to change, thereby achieving accurate measurement of the vibration through the frequency change. By calibrating the vibration-resonant frequency sensitivity of the upper resonant beam and the lower resonant beam, the accuracy of the vibration measurement can be further improved to meet the requirements for high-precision vibration detection. Secondly, due to the use of the capacitive sensing principle, the vibration signal of the resonant beam is detected by the capacitance change of the upper drive electrode, the upper sensing electrode, the lower drive electrode and the lower sensing electrode. This solution has the advantages of high integration and low power consumption.

[0054] In an optional embodiment, the sensor also obtains a corresponding relationship between the vacuum degree and the resonant frequency based on the effect of air damping on the vibration of the resonant probe, and detects the vacuum degree according to the corresponding relationship between the vacuum degree and the resonant frequency.

[0055] Specifically, for a resonant beam device, the quality factor can be defined as the ratio of the average energy stored to the energy lost per unit period. Each loss mechanism will act on the resonator separately to produce energy loss, such as viscous damping, anchor point damping, material damping, thermoelastic damping (TED), and other forms of energy dissipation. The total quality factor Q of the system and various losses can be expressed by the following formula:

[0056]

[0057] Among them, the subscript individual represents the quality factor of each independent loss mechanism, the subscript air-damping represents the quality factor caused by air damping, the subscript TED represents the quality factor caused by thermoelastic dissipation, the subscript anchor-loss represents the quality factor caused by support loss, and the subscript other represents the quality factor caused by other forms of loss; among them, the relationship between the quality factor caused by air damping and the changes in temperature and air pressure, air damping can be expressed by the following formula:

[0058]

[0059] Among them, k b is the Boltzmann constant, P is the air pressure of the resonator working environment, T is the temperature of the resonant beam, and C is a constant related to the surface area perpendicular to the vibration direction, the modal vibration shape of the resonator, the wall collision effect, etc. When air damping is dominant as the Q value, the vacuum degree-resonance amplitude sensitivity is obtained through gas pressure calibration. The resonance amplitude of the resonant beam will be negatively correlated with the vacuum degree. By reading the resonance amplitude, the vacuum degree can be measured.

[0060] Example 2

[0061] This embodiment makes improvements based on the resonant multi-parameter sensor proposed in Embodiment 1.

[0062] In an optional embodiment, the detection circuit 2 includes a signal demodulation module, a resonant frequency calculation module and a driving module; the signal demodulation module is used to perform multi-channel orthogonal demodulation on the current signal output by the resonant probe 1 and convert it into a digital signal; the resonant frequency calculation module calculates the resonant frequency based on the digital signal; the driving module is used to convert the digital signal into an analog signal, and drive the resonant probe 1 based on the analog signal.

[0063] In this embodiment, a closed-loop signal processing system is formed by setting up the coordination of the signal demodulation module, the resonant frequency calculation module and the driving module. Among them, the signal demodulation module converts the current signal output by the resonant probe 1 into a digital signal through multi-channel orthogonal demodulation, and can effectively extract the amplitude information in the signal. The resonant frequency calculation module calculates the resonant frequency based on the digital signal, realizing the accurate quantification of the sensing parameter. The driving module converts the digital signal into an analog signal and drives the resonant probe 1, forming a closed-loop excitation, ensuring the continuous and stable operation of the resonant system, and improving the measurement accuracy and reliability of the sensor.

[0064] In an optional embodiment, the signal demodulation module includes an analog-to-digital converter, a digitally controlled oscillator and a low-pass filter. The analog-to-digital converter converts the current signal output by the resonant probe 1 into a digital signal. The digital signal is demodulated and multiplied with the orthogonal reference signal generated by the digitally controlled oscillator and input into the low-pass filter. The filtered signal is input into the resonant frequency calculation module.

[0065] like Figure 6 As shown, it is a circuit structure diagram of the detection circuit 22.

[0066] Specifically, the signal demodulation module also includes a transimpedance amplifier circuit 201, which amplifies the weak current signal generated by the resonant probe 11, converts the analog voltage signal into a digital signal through an analog-to-digital converter 202, multiplies the sine signal generated by the digital control oscillator and the sine signal with a 90-degree phase increase, respectively, and then passes through a low-pass filter 203 and inputs the phase and amplitude calculation module 204. The phase and amplitude calculation module 204 calculates the signal phase error and amplitude, and the phase error is added to the additional phase θ and input to the proportional-integral controller 205. The generated signal undergoes a phase change and feedback controls the output frequency of the digital control oscillator NCO.

[0067] Further optionally, the digital controlled oscillator includes a frequency register 206, a phase accumulator 207 and a sine lookup table 208; wherein the phase accumulator 207 performs an integration function, and the sine lookup table 208 generates a frequency signal to achieve phase locking, so that the phase error signal approaches zero.

[0068] In this embodiment, the current signal output by the resonant probe 1 is converted into a digital signal through an analog-to-digital converter, which avoids attenuation and interference in the transmission process of the analog signal and improves the integrity of the signal. The orthogonal reference signal generated by the digital control oscillator is demodulated and multiplied with the digital signal to accurately extract the amplitude and phase information of the signal. The low-pass filter filters the demodulated signal to effectively suppress high-frequency noise and interference components and ensure the purity of the output signal. This digital demodulation scheme not only simplifies the circuit structure and reduces system power consumption, but also improves the stability and reliability of the demodulation process, which is conducive to improving the overall performance of the sensor.

[0069] In an optional embodiment, the driving module includes an anti-aliasing filter 209 and an analog-to-digital converter 2010, and the anti-aliasing filter 209 receives the phase signal output by the digital control oscillator for filtering, and inputs the filtered signal into the analog-to-digital converter 2010 to convert it into an analog signal to drive the resonant probe 1.

[0070] In this embodiment, the performance of the resonant multi-parameter sensor system is significantly improved by introducing an anti-aliasing filter 209 and an analog-to-digital converter 2010. The anti-aliasing filter 209 effectively filters out high-frequency noise and unnecessary frequency components output by the digital control oscillator to prevent signal aliasing, thereby ensuring the accuracy of the resonant frequency; the analog-to-digital converter converts the filtered signal into an analog signal to drive the resonant probe 1 to ensure signal stability and accuracy. This design can improve the response speed, measurement accuracy and anti-interference ability of the probe, so that the sensor can still stably and accurately perform multi-parameter detection in a complex environment, meeting the needs of high-precision data acquisition.

[0071] Example 3

[0072] This embodiment provides a resonant multi-parameter detection device, including at least one resonant multi-parameter sensor provided in Embodiment 1 and Embodiment 2.

[0073] The terms used in the drawings are for illustrative purposes only and should not be construed as limiting this patent.

[0074] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A resonant multi-parameter sensor, characterized in that: include: A plurality of resonant probes and a plurality of detection circuits; the resonant probes are respectively connected to corresponding detection circuits; The resonant probe comprises a resonant beam structure for detecting different environmental parameters; The detection circuit is used to perform multi-channel orthogonal demodulation on the current signal output by the resonant probe to obtain the resonant frequency, and output the parameter measurement result based on the corresponding relationship between the resonant frequency and the environmental parameter.

2. A resonant multi-parameter sensor according to claim 1, characterized in that: The resonant probe includes: a resonant temperature sensing probe, a resonant magnetic field probe and a resonant vibration probe.

3. A resonant multi-parameter sensor according to claim 2, characterized in that: The resonant temperature sensing probe includes a DC bias electrode, a driving electrode, a sensing electrode and a temperature-sensitive resonant beam that changes the resonant frequency based on temperature; one end of the temperature-sensitive resonant beam is connected to the DC bias electrode, and the driving electrode and the sensing electrode are placed opposite to each other on both sides of the temperature-sensitive resonant beam; the driving electrode receives an AC voltage signal output by a detection circuit, and the AC voltage causes the temperature-sensitive resonant beam to start resonant motion, and the sensing electrode senses the vibration signal of the temperature-sensitive resonant beam and outputs it to the detection circuit.

4. A resonant multi-parameter sensor according to claim 2, characterized in that: The resonant magnetic field probe includes a DC bias electrode, a driving electrode, a sensing electrode, a Lorentz force generating beam and a first resonant beam; both ends of the first resonant beam are connected to the Lorentz force generating beam, the Lorentz force generating beam is connected to the DC bias electrode, and the driving electrode and the sensing electrode are placed opposite to each other on both sides of the first resonant beam; the driving electrode receives the AC voltage signal output by the detection circuit and outputs it to the Lorentz force generating beam, the Lorentz force generated in the Lorentz force generating beam generates stress between the Lorentz force generating beam and the first resonant beam, and the sensing electrode senses the vibration signal of the first resonant beam and outputs it to the detection circuit.

5. The resonant multi-parameter sensor according to claim 2, characterized in that: The resonant vibration probe includes a DC bias electrode, a driving electrode, a sensing electrode, a mass block and a second resonant beam; one end of the second resonant beam is connected to the DC bias electrode, the driving electrode and the sensing electrode are placed opposite to each other on both sides of the second resonant beam, and the mass block is connected to the other end of the second resonant beam; the driving electrode receives an AC voltage signal output by a detection circuit, the AC voltage causes the second resonant beam to start resonant motion, the mass block changes the stress between it and the second resonant beam based on vibration, and the sensing electrode senses the vibration signal of the second resonant beam and outputs it to the detection circuit.

6. A resonant multi-parameter sensor according to claim 2, characterized in that: The sensor also obtains the corresponding relationship between the vacuum degree and the resonant frequency based on the influence of air damping on the vibration of the resonant probe, and detects the vacuum degree according to the corresponding relationship between the vacuum degree and the resonant frequency.

7. A resonant multi-parameter sensor according to any one of claims 1 to 6, characterized in that: The detection circuit includes a signal demodulation module, a resonant frequency calculation module and a driving module; the signal demodulation module is used to perform multi-channel orthogonal demodulation on the current signal output by the resonant probe and convert it into a digital signal; the resonant frequency calculation module calculates the resonant frequency based on the digital signal; the driving module is used to convert the digital signal into an analog signal, and drive the resonant probe based on the analog signal.

8. The resonant multi-parameter sensor according to claim 7, characterized in that: The signal demodulation module includes an analog-to-digital converter, a digitally controlled oscillator and a low-pass filter. The analog-to-digital converter converts the current signal output by the resonant probe into a digital signal. The digital signal is demodulated and multiplied with the orthogonal reference signal generated by the digitally controlled oscillator and input into the low-pass filter. The filtered signal is input into the resonant frequency calculation module.

9. The resonant multi-parameter sensor according to claim 8, characterized in that: The driving module includes an anti-aliasing filter and an analog-to-digital converter. The anti-aliasing filter receives a phase signal output by a digitally controlled oscillator for filtering, and inputs the filtered signal into the analog-to-digital converter to convert it into an analog signal to drive the resonant probe.

10. A resonant multi-parameter detection device, characterized in that: The device comprises at least one resonant multi-parameter sensor as claimed in any one of claims 1 to 9.

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