A high vacuum degree measuring sensor

Abstract

This invention relates to the sensing and electronics industries, and particularly to a high vacuum measurement sensor. It includes a power conversion module that converts the power supply voltage into driving units for a piezoresistive measuring sensor, a Pirani measuring sensor, and a silicon resonant measuring sensor, as well as the operating voltage required by a core data processing unit. Each driving circuit drives its corresponding sensor, and each filtering and amplification circuit amplifies the data measured by the corresponding sensor, transmitting the amplified signal to the core data processing unit. The core data processing unit selects either the piezoresistive or silicon resonant measuring sensor based on the detection result of the Pirani measuring sensor, and performs compensation calibration based on the measured value of the selected sensor combined with the measured value of the Pirani measuring sensor. The calibrated data is then output through a communication interface circuit. This invention improves the measurement accuracy of the vacuum sensor and enhances its zero-bias stability.

Description

Technical Field

[0001] This invention relates to the sensing and electronics industries, and particularly to a high vacuum measurement sensor. Background Technology

[0002] Vacuum refers to the gaseous state below one standard atmosphere. Vacuum measurement is widely used in industrial equipment and instruments in semiconductor manufacturing, advanced materials processing, aerospace, nuclear power generation, and energy transportation. There are various methods for measuring vacuum, and different technologies differ significantly for high vacuum measurements, each with its own advantages at different vacuum measurement stages. Vacuum measurement technologies can be mainly divided into three different mechanisms: piezoresistive, Pirani, and resonant. All three have mature applications, but each detection mechanism has its own shortcomings when measuring vacuum individually. For example, resonant pressure is suitable for high vacuum but is prone to data jumps in low vacuum; Pirani is suitable for mid-range measurements but is easily affected by temperature; and piezoresistive is suitable for low vacuum detection.

[0003] This invention designs corresponding detection circuits and algorithms based on the application and signal output of three different vacuum measurement technologies. This patent uses a microcontroller as the core component, primarily to drive and acquire signals from the Pirani vacuum measuring element, resonant vacuum measuring element, and piezoresistive vacuum measuring element, and performs calculations, calibrations, and applications based on algorithms. Summary of the Invention

[0004] To address the problems existing in current vacuum degree measurement methods, this invention proposes a high vacuum degree measurement sensor, comprising: a power supply, a power conversion module, a piezoresistive measurement sensor, a Pirani measurement sensor, a silicon resonant measurement sensor, and driving circuits, filtering and amplification processing circuits for each sensor, a core data processing unit, and a communication interface circuit. The power conversion module converts the power supply voltage into the operating voltage required by the driving units of the piezoresistive, Pirani, and silicon resonant measurement sensors, as well as the core data processing unit. Each driving circuit drives its corresponding sensor, and each filtering and amplification processing circuit amplifies the data measured by the corresponding sensor, transmitting the amplified signal to the core data processing unit. The core data processing unit selects either the piezoresistive or silicon resonant measurement sensor based on the detection result of the Pirani measurement sensor, and performs compensation and calibration based on the measured values ​​of the selected sensor and the Pirani measurement sensor. The compensated and calibrated data is then output through the communication interface circuit.

[0005] Furthermore, the power conversion module has an input voltage of 24V DC, which is converted into 3.3V DC, 4.086V DC and 5V DC. The 3.3V DC is used to power the core data processing unit, the 4.086V DC is used to power the Pirani measurement sensor, and the 5V DC is used to power the silicon resonant measurement sensor and the piezoresistive measurement sensor.

[0006] Furthermore, the FPGA digital processing chip provides a stable sinusoidal resonant signal and simultaneously constructs a negative feedback loop to modulate the output frequency in real time, providing a 5V sinusoidal excitation source for the silicon resonant measurement sensor.

[0007] Furthermore, the power conversion module uses the SGM61720 switching power management chip to convert 24V DC voltage to 5.32V DC voltage, and then converts the 5.32V DC voltage to 3.3V DC voltage, 4.086V DC voltage and 5V DC voltage respectively through LDO chips.

[0008] Furthermore, the LDO chip is SGM2211.

[0009] Furthermore, the core data processing unit determines whether the measurement signal of the Pirani measurement sensor is higher than a set threshold. If it is higher, the piezoresistive measurement sensor is selected, meaning that the piezoresistive measurement sensor and the Pirani measurement sensor perform measurements simultaneously. If it is not higher, the silicon resonant measurement sensor is selected, meaning that the silicon resonant measurement sensor and the Pirani measurement sensor perform measurements simultaneously.

[0010] Furthermore, the piezoresistive measurement sensor has a measurement range of 20 mbar to 1000 mbar; the Pirani measurement sensor has a measurement range of 1 × 10⁻⁶ mbar. -3 mbar~50mbar; the silicon resonant measurement sensor has a measurement range of 5×10 -6 mbar~3×10 - 3 mbar.

[0011] Furthermore, a pre-trained neural network is used to compensate and calibrate the input signal. When the signal from the Pirani measurement sensor is higher than a set threshold, the input signal includes the measurement signals from the piezoresistive measurement sensor and the Pirani measurement sensor; otherwise, the input signal includes the measurement signals from the silicon resonant measurement sensor and the Pirani measurement sensor.

[0012] Compared with existing technologies, this invention addresses the accuracy problem in vacuum sensor detection by using machine learning to compensate and calibrate measurements from two different types of sensors, thereby greatly improving the accuracy of the measurement results. Attached Figure Description

[0013] Figure 1This is a schematic diagram of a high vacuum degree measurement sensor according to the present invention;

[0014] Figure 2 This is a schematic diagram of the multi-source detection circuit structure for the high-vacuum sensor of the present invention;

[0015] Figure 3 This invention relates to a multi-power supply circuit architecture;

[0016] Figure 4 This is a schematic diagram illustrating the implementation principle of the multi-channel power supply of the present invention;

[0017] Figure 5 This is a functional diagram of the multi-source signal acquisition of the present invention;

[0018] Figure 6 The principle of multi-source signal acquisition in this invention Figure 1 ;

[0019] Figure 7 The principle of multi-source signal acquisition in this invention Figure 2 ;

[0020] Figure 8 This is the implementation flow of the compensation calibration strategy model algorithm of the present invention;

[0021] Among them, GND is the ground terminal; J1 is the Pirani measurement sensor; J2 is the piezoresistive measurement sensor; J3 is the silicon resonant measurement sensor; L4 is the fourth inductor; C3 is the third capacitor; C9 is the ninth capacitor; C14 is the fourteenth capacitor; C15 is the fifteenth capacitor; C16 is the sixteenth capacitor; C17 is the seventeenth capacitor; C21 is the twenty-first capacitor; C23 is the twenty-third capacitor; C24 is the twenty-fourth capacitor; C25 is the twenty-fifth capacitor; C27 is the twenty-seventh capacitor; C28 is the twenty-eighth capacitor; C29 is the twenty-ninth capacitor; C32 is the thirty-second capacitor; C33 is the thirty-third capacitor; C34 is the thirty-fourth capacitor; and C35 is the thirty-fifth capacitor.

[0022] C36, the 36th capacitor; C37, the 37th capacitor; C38, the 38th capacitor; C39, the 39th capacitor; C40, the 40th capacitor; C41, the 41st capacitor; C57, the 57th capacitor; R2, the 2nd resistor; R3, the 3rd resistor; R7, the 7th resistor; R9, the 9th resistor; R11, the 11th resistor; R12, the 12th resistor; R13, the 13th resistor; R14, the 14th resistor; R15, the 15th resistor; R16, the 16th resistor; R18, the 18th resistor; R20, the 20th resistor; R21... The twenty-first resistor; R23, the twenty-third resistor; R24, the twenty-fourth resistor; R25, the twenty-fifth resistor; R35, the thirty-fifth resistor; R36, the thirty-sixth resistor; R37, the thirty-seventh resistor; R38, the thirty-eighth resistor; R39, the thirty-ninth resistor; R41, the forty-first resistor; R42, the forty-second resistor; R43, the forty-third resistor; R44, the forty-fourth resistor; R45, the forty-fifth resistor; R46, the forty-sixth resistor; R47, the forty-seventh resistor; R48, the forty-eighth resistor; R50, the fiftieth resistor. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] This invention proposes a high vacuum degree measurement sensor, comprising: a power supply, a power conversion module, a piezoresistive measurement sensor, a Pirani measurement sensor, a silicon resonant measurement sensor, and driving circuits, filtering and amplification processing circuits for each sensor, a core data processing unit, and a communication interface circuit. The power conversion module converts the power supply voltage into the operating voltage required by the driving units of the piezoresistive, Pirani, and silicon resonant measurement sensors, as well as the core data processing unit. Each driving circuit drives its corresponding sensor, and each filtering and amplification processing circuit amplifies the data measured by the corresponding sensor, transmitting the amplified signal to the core data processing unit. The core data processing unit selects either the piezoresistive or silicon resonant measurement sensor based on the detection result of the Pirani measurement sensor, and performs compensation and calibration based on the measured values ​​of the selected sensor combined with the measured values ​​of the Pirani measurement sensor. The compensated and calibrated data is then output through the communication interface circuit.

[0025] This embodiment proposes a high vacuum degree measurement sensor, which addresses three different electrical drive and signal readout requirements corresponding to three different sensing mechanism structures. The piezoresistive and Pirani sensing structures can be driven by a constant voltage and signal acquisition is achieved by reading differential-mode voltage data, while the microresonator requires alternating voltage excitation and signal acquisition is achieved by reading capacitance data. Crosstalk can exist between different driving and readout methods. Simultaneously driving multiple sensing structures and processing data puts pressure on the circuit's power consumption. Therefore, designing a low-power, multi-channel driving and readout circuit is the key aspect of this application.

[0026] For the three different sensing mechanisms, there are three measurement ranges. The data processing of the overlapping ranges determines the accuracy of the sensor. In this application, the overlapping data is fully utilized for the self-calibration and self-compensation of the sensor. This strategy can significantly extend the calibration cycle of the device and can perform self-diagnosis when an abnormality occurs in a certain sensing mechanism structure in the sensor.

[0027] The design of vacuum sensors must meet the requirements of a wide range of inputs, while also achieving constant voltage control across multiple voltage domains within a confined space to meet the power supply needs of the multiple sensitive structures and signal processing circuits within the sensor. Additionally, the input points must be protected to suppress ripple interference introduced by the external environment.

[0028] In this embodiment, response thresholds for signal acquisition are defined for three sensitive structures: piezoresistive, Pirani, and resonant. The microprocessor chip uses analog on / off switches to control the signal acquisition of different sensitive structures by making logical judgments on the response thresholds. At the same time, a signal acquisition circuit with interference suppression and low power consumption is designed to meet the requirements of multi-signal interference and low power consumption.

[0029] This embodiment employs a wide-range data processing algorithm. For wide-range data acquired from multiple sensitive structures, signal filtering and noise reduction processing is required before calibration to suppress the influence of noise. The calibration processing of multi-source wide-range data mainly includes independent calibration processing of data from each sensitive structure and calibration processing of overlapping segment data.

[0030] The intelligent strategy algorithm compensation design for wide-range data processing employed in this embodiment addresses the challenges of multi-sensitive structure signal coupling within different measurement ranges in vacuum sensors. This results in large data processing volumes and signal overlap. The intelligent strategy optimizes data processing, improving microprocessor efficiency, shortening signal response time, and enhancing sensor measurement accuracy. Considering the future automation and unmanned operation requirements of vacuum sensors in industrial settings, this patent incorporates anomaly detection and alarm strategies into the algorithm.

[0031] This embodiment uses a high-stability constant voltage drive module to preprocess and protect the input voltage. Based on practical considerations, the voltage thresholds are as follows:

[0032] ① 24V is used as the main power supply to provide a reference voltage for subsequent voltage conversion;

[0033] ② Design a DC 5V power supply for driving a piezoresistive pressure sensor, a resonant digital processing chip, and peripheral circuitry;

[0034] ③ Design a 4.096V DC power supply for the Pirani sensor;

[0035] ④ A 5V sinusoidal excitation source is used to power the resonant pressure sensor. The FPGA digital processing chip provides a stable sinusoidal resonant signal and at the same time constructs a negative feedback loop to modulate the output frequency in real time to ensure the stable operation of the resonant sensor.

[0036] ⑤ Design a 3.3V power supply for powering the communication interface circuit, which serves as the sensor's external interface. This is implemented through a microprocessor and external devices and can support different data communication standards.

[0037] Solution implementation schematic design description:

[0038] like Figure 4 In this embodiment, the SGM61720 switching power management chip is used to convert 24V DC voltage to 5.32V DC voltage. The specific circuit implementation includes:

[0039] Pin 2 of the SGM61720, capacitors 32, 33, 34, and resistor 13 are connected to the power input terminal, i.e., the 24V DC voltage terminal.

[0040] The other ends of capacitors 32, 33, and 34 are connected to the ground terminal.

[0041] The other end of the thirteenth resistor is connected to pin 3 of the SGM61720;

[0042] Pin 4 of the SGM61720 is connected to one end of the 40th capacitor; the other end of the 40th capacitor is connected to the ground terminal and pins 9 and 7 of the SGM61720; pin 9 of the SGM61720 is the heat dissipation pin of the SGM61720 chip.

[0043] One end of pin 6, the fourth inductor, the thirty-sixth capacitor, the fifteenth resistor, the thirty-seventh capacitor, the thirty-eighth capacitor, and the thirty-ninth capacitor of the SGM61720 are connected together and used as the output terminal to output a voltage of 5.032V.

[0044] The other ends of capacitors 37, 38, and 39 are connected to the ground terminal.

[0045] The other end of the fifteenth resistor is connected to the other end of the thirty-sixth capacitor, one end of the forty-first capacitor, pin 5 of the SGM61720, and one end of the sixteenth resistor. The other end of the sixteenth resistor is grounded.

[0046] The other end of the forty-first capacitor is connected to one end of the fourteenth resistor;

[0047] The other end of the fourteenth resistor is connected to the other end of the fourth inductor, one end of the thirty-fifth capacitor, and tube 8 of the SGM61720.

[0048] The other end of the 35th capacitor is connected to pin 1 of the SGM61720;

[0049] In this embodiment, the SGM2211 LDO chip is used to convert 24V DC voltage to 3.3V DC voltage, 4.086V DC voltage, and 5V DC voltage. The circuit structure for obtaining the 5V DC voltage includes:

[0050] A 5.32V DC voltage is connected as the input terminal to pin 1 of the SGM2211 and one end of the ninth resistor;

[0051] The other end of the ninth resistor is connected to pin 3 of the SGM2211;

[0052] Pin 2 of the SGM2211 is grounded;

[0053] Pin 4 of the SGM2211 is connected to one end of the ninth capacitor and the ground terminal;

[0054] The other end of the ninth capacitor is connected to pin 5 of the SGM2211 as the output terminal, which outputs a 5V DC voltage.

[0055] The circuit structure for obtaining a 3.3V DC voltage includes:

[0056] A 5.32V DC voltage is connected as the input terminal to pin 1 of the SGM2211, one end of the twelfth resistor, and one end of the fourteenth resistor.

[0057] The other end of the fourteenth capacitor is connected to pin 2 of the SGM2211 and the ground terminal;

[0058] The other end of the twelfth resistor is connected to pin 3 of the SGM2211;

[0059] Pin 4 of the SGM2211 is connected to one end of the fifteenth capacitor and the ground terminal;

[0060] The other end of the fifteenth capacitor is connected to pin 5 of the SGM2211 as an output terminal, outputting a 3.3V DC voltage.

[0061] The circuit structure for obtaining a 4.096V DC voltage includes:

[0062] A 5.32V DC voltage is connected as the input terminal to pin 1 of the SGM2211, one end of the 23rd resistor, and one end of the 16th capacitor.

[0063] The other end of the sixteenth capacitor is connected to pin 2 of the SGM2211 and the ground terminal;

[0064] The other end of the twenty-third resistor is connected to pin 3 of the SGM2211;

[0065] Pin 4 of the SGM2211 is connected to one end of the 24th and 25th resistors;

[0066] The other end of the twenty-fourth resistor is connected to the eighteenth capacitor and the ground terminal;

[0067] Pin 5 of the SGM2211 is connected to the other end of the 25th resistor and the other end of the 18th capacitor to form an output terminal, which outputs a DC voltage of 4.096V.

[0068] The circuit in this embodiment determines the signal acquisition state by judging the response thresholds of three sensitive structures. The signal acquisition state judgment logic is shown in the figure. First, the Pirani sensitive structure is controlled to acquire signals. If the response signal is higher than its own high response threshold, the piezoresistive structure and the Pirani structure are controlled to acquire signals simultaneously. When the response signal of the piezoresistive structure is lower than its own low response threshold, the piezoresistive structure is controlled to stop acquiring signals. The Pirani structure and the resonant structure operate in the same way.

[0069] The ranges of the three sensitive mechanism structures are divided into:

[0070] ① The measurement range of the piezoresistive element is 20mbar~1000mbar, and that of the Pirani type is 1×10 -3 mbar~50mbar, resonant type is 5×10 -6 mbar~3×10 -3 mbar;

[0071] ② The overlap between the piezoresistive and Pirani types is 20 mbar to 50 mbar;

[0072] ③ The overlap between the microresonator and the Pirani plate is 1×10. -3 mbar~3×10 -3 mbar.

[0073] During the detection of the ambient vacuum level, the overlapping data is used to calibrate and compensate the medium vacuum section based on the high vacuum section, and to calibrate and compensate the low vacuum section based on the medium vacuum section. This achieves data overlap section calibration processing of the sensor and improves reliability.

[0074] In this embodiment, the filtering and amplification processing circuit is implemented using the SGM8061 chip, wherein the filtering and amplification processing circuit of the Pirani measurement sensor includes:

[0075] The output terminal of the Pirani measurement sensor is connected to one end of the forty-third resistor. The other end of the forty-third resistor is connected to one end of the eleventh resistor, one end of the twenty-fourth capacitor, and one end of the seventh resistor, which are then connected to pin 3 of the SGM8061.

[0076] The other end of the eleventh resistor is connected to the power supply terminal, i.e., 4.086V DC voltage;

[0077] The other end of the twenty-fourth capacitor is grounded.

[0078] The other end of the seventh resistor is connected to one end of the forty-fifth resistor, one end of the forty-fourth resistor, and one end of the twenty-third capacitor at pin 1 of the SGM8061.

[0079] The other end of the forty-fourth resistor is connected to the other end of the twenty-third capacitor, pin 4 of the SGM8061, and the pressure output signal P+ of the Pirani measurement sensor.

[0080] Pin 2 of the SGM8061 is grounded;

[0081] Pin 5 of the SGM8061 is connected to a 5V DC voltage.

[0082] The other end of the forty-fifth resistor and one end of the twenty-fifth capacitor are connected together to serve as the output of the filter amplification circuit.

[0083] The other end of the 25th capacitor is grounded.

[0084] The filtering and amplification circuit of the piezoresistive measurement sensor includes:

[0085] The output terminal of the piezoresistive measurement sensor is connected to one end of the forty-eighth resistor, the other end of the forty-eighth resistor is connected to pin 3 of the SGM8061 and one end of the twenty-eighth capacitor, and the other end of the twenty-eighth capacitor is grounded.

[0086] Pin 4 of the SGM8061 is connected to one end of the 47th resistor, one end of the 27th capacitor, and one end of the 2nd resistor, while the other end of the 47th resistor is grounded.

[0087] The other end of the twenty-seventh capacitor, the other end of the second resistor, one end of the forty-sixth resistor, and pin 1 of the SGM8061 are connected together.

[0088] The other end of the forty-sixth resistor is connected to one end of the twenty-sixth capacitor as the output terminal, and the other end of the twenty-sixth capacitor is grounded.

[0089] Pin 5 of the SGM8061 is connected to a 5V DC voltage and one end of the 29th capacitor, while the other end of the 29th capacitor is grounded.

[0090] Pin 2 of the SGM8061 is grounded.

[0091] The filtering and amplification circuit of the silicon resonant measurement sensor includes:

[0092] The output terminal of the silicon resonant measurement sensor is connected to one end of the thirty-seventh resistor, and the other end of the thirty-seventh resistor is connected to pin 3 of the SGM8061 and one end of the thirty-eighth resistor.

[0093] The other end of the thirty-eighth resistor is connected to pin 1 of the SGM8061, one end of the fifty-seventh capacitor, and one end of the thirty-ninth resistor to form an output terminal;

[0094] The other end of the 57th capacitor, the other end of the 39th resistor, pin 2 of the SGM8061, and the ground terminal are connected together.

[0095] Pin 4 of SGM8061 is connected to one end of the 35th resistor and one end of the 36th resistor, and the other end of the 36th resistor is grounded.

[0096] The other end of the 35th resistor is connected to a 3.3V DC voltage and a pin of the SGM8061.

[0097] In this embodiment, the core data processing unit uses the GD32F303CET6 chip as the main control unit. The main control unit serves as the carrier of program code and algorithm model, and collects and processes the electrical signals of the three sensors. The piezoresistive and Pirani sensors are acquired using analog AD voltage acquisition, while the resonant pressure sensor is acquired using a timer to collect sinusoidal pulses. In the figure, P3 serves as the interface for program download.

[0098] In addition, the use of the GD25Q32 FLASH chip as extended memory enables the execution of code for algorithm models with large amounts of data. The FLASH chip and the MCU chip communicate with each other via SPI.

[0099] The design of the intelligent compensation calibration strategy model algorithm includes the following:

[0100] 1) Self-calibration and self-compensation strategy for overlapping segments

[0101] To address the overlap of zero-bias and transition signals caused by measurements, it is necessary to decouple complex signals and achieve self-calibration of the high-precision signal to the low-precision signal. A deep learning-based backlash decoupling and intelligent zero-bias calibration algorithm for the overlapping segment is introduced.

[0102] 2) Research on lightweighting and edge-porting of deep learning networks

[0103] Large-scale deep learning models built in the cloud or on servers cannot be directly ported to edge devices. By using structural sparsity methods to compress and prune deep learning networks, the model size is significantly reduced while maintaining the original model's performance, thus achieving lightweight deep learning networks.

[0104] 3) Anomaly detection and alarm strategy

[0105] During the training process of the established model, the threshold setting includes real-time identification of anomalies and alarms based on the classification of anomalies.

[0106] (4) Product realization and transformation

[0107] Based on the above design principles, the product can be realized and transformed. The schematic diagram is converted into a circuit board, defined as the power communication board diagram and the CPU and acquisition board diagram. The debugged circuit board can achieve the patent objectives after testing. The circuit board diagram can be seen in the attached drawings.

[0108] In the description of this invention, it should be understood that the terms "coaxial," "bottom," "one end," "top," "middle," "other end," "upper," "side," "top," "inner," "outer," "front," "center," "both ends," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0109] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," "fixing," "rotation," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0110] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high vacuum degree measuring sensor, characterized by, include: The system includes a power supply, a power conversion module, a piezoresistive measurement sensor, a Pirani measurement sensor, a silicon resonant measurement sensor, and driving circuits, filtering and amplification circuits for each sensor, a core data processing unit, and a communication interface circuit. The power conversion module converts the power supply voltage into the operating voltage required by the driving units of the piezoresistive, Pirani, and silicon resonant measurement sensors, as well as the core data processing unit. Each driving circuit drives its corresponding sensor, and each filtering and amplification circuit amplifies the data measured by the corresponding sensor, transmitting the amplified signal to the core data processing unit. The core data processing unit selects either a piezoresistive sensor or a silicon resonant sensor based on the detection results of the Pirani sensor, and performs compensation and calibration based on the measurement values ​​of the selected sensor and the Pirani sensor. The compensated and calibrated data is then output through the communication interface circuit.

2. The high vacuum level measuring sensor according to claim 1, characterized in that The power conversion module has an input voltage of 24V DC and converts it into 3.3V DC, 4.086V DC, and 5V DC. The 3.3V DC is used to power the core data processing unit, the 4.086V DC is used to power the Pirani measurement sensor, and the 5V DC is used to power the silicon resonant measurement sensor and the piezoresistive measurement sensor.

3. A high vacuum level measuring sensor according to claim 2, characterized in that The FPGA digital processing chip provides a stable sinusoidal resonant signal and constructs a negative feedback loop to modulate the output frequency in real time, providing a 5V sinusoidal excitation source for the silicon resonant measurement sensor.

4. The high vacuum level measuring sensor according to claim 2, characterized in that The power conversion module uses the SGM61720 switching power management chip to convert 24V DC voltage to 5.32V DC voltage. Then, the 5.32V DC voltage is converted into 3.3V DC voltage, 4.086V DC voltage and 5V DC voltage respectively through LDO chips.

5. A high vacuum level measuring sensor according to claim 4, characterized in that The LDO chip is SGM2211.

6. The high vacuum level measuring sensor according to claim 1, characterized in that The core data processing unit determines whether the measurement signal of the Pirani measuring sensor is higher than a set threshold. If it is higher, the piezoresistive measuring sensor is selected, meaning that the piezoresistive measuring sensor and the Pirani measuring sensor perform measurements simultaneously. If it is not higher, the silicon resonant measuring sensor is selected, meaning that the silicon resonant measuring sensor and the Pirani measuring sensor perform measurements simultaneously.

7. A high vacuum level measuring sensor according to claim 6, characterized in that The piezoresistive measuring sensor has a measurement range of 20 mbar to 1000 mbar; the Pirani measuring sensor has a measurement range of 1 × 10⁻⁶ mbar. -3 mbar~50mbar; the silicon resonant measurement sensor has a measurement range of 5×10 -6 mbar~3×10 -3 mbar.

8. The high vacuum level measuring sensor according to claim 6, characterized in that A pre-trained neural network is used to compensate and calibrate the input signal. When the signal from the Pirani measurement sensor is higher than a set threshold, the input signal includes the measurement signals from the piezoresistive measurement sensor and the Pirani measurement sensor; otherwise, the input signal includes the measurement signals from the silicon resonant measurement sensor and the Pirani measurement sensor.

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