Transmitter circuit board connecting structure of diffused silicon pressure sensor

Abstract

The invention discloses a transmitter circuit board connecting structure of a diffused silicon pressure sensor, which relates to the technical field of industrial control instruments, and comprises a sensor main body, a bottom circuit board, a top circuit board, a connecting mechanism, a fixing mechanism and a heat dissipation structure, the top layer circuit board is embedded in the sensor main body and located above the bottom layer circuit board, the connecting mechanism is arranged between the bottom layer circuit board and the top layer circuit board, the fixing mechanism is arranged between the sensor main body and the bottom layer circuit board, and the heat dissipation structure is arranged between the sensor main body and the bottom layer circuit board. Through a layered circuit board structure, plug-in connection and heat dissipation isolation design, and in combination with software temperature compensation modeling, high-precision measurement of the diffused silicon pressure sensor without hardware temperature compensation in a wide temperature region is realized, and the temperature adaptation range, the compensation precision and the structural reliability are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of industrial control instrumentation technology, and in particular to a transmitter circuit board connection structure for a diffused silicon pressure sensor. Background Technology

[0002] Diffused silicon sensors are a new type of semiconductor sensor that has been widely used in industrial automation, aerospace, and medical devices due to their advantages such as high sensitivity, high stability, miniaturization, and integration. The principle of diffused silicon sensors is mainly based on the piezoresistive effect of silicon. When silicon is subjected to external force, its resistance changes. By accurately measuring the change in resistance, various physical quantities, such as pressure, temperature, and acceleration, can be measured.

[0003] Transmitters convert non-standard electrical signals from sensors into standard electrical signals. Depending on their industrial applications, they are typically categorized as temperature, pressure, and level transmitters. Transmitters offer high measurement accuracy, meeting the measurement and control needs of various industrial processes. In practical applications of pressure sensors, temperature variations significantly impact measurement accuracy, leading to errors in the results. Temperature compensation of the transmitter is necessary to counteract drift caused by temperature changes, ensuring that the sensor outputs the correct pressure at different temperatures.

[0004] However, while hardware temperature compensation in transmitters offers stable compensation without software intervention, it typically relies on experience-based tuning, limiting its flexibility and accuracy, particularly regarding the temperature compensation range. Under the premise of a nominal accuracy of 0.1%FS, industry-standard hardware temperature compensation usually only achieves 0-70℃, a very limited range significantly smaller than the common industrial temperature range of -40-85℃. In other words, within the ambient temperature range where the instrument can operate, the sensor cannot achieve full-temperature compensation, often failing to meet the accuracy requirements. Furthermore, it imposes certain requirements on assembly space and methods, making it unsuitable for some sensor needs. Therefore, we propose a transmitter circuit board connection structure for a diffused silicon pressure sensor. Summary of the Invention

[0005] The purpose of this invention is to provide a transmitter circuit board connection structure for a diffused silicon pressure sensor to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a transmitter circuit board connection structure for a diffused silicon pressure sensor, comprising: Sensor body; The bottom circuit board is embedded inside the sensor body; A top-level circuit board, which is embedded inside the sensor body and located above the bottom-level circuit board; A connecting mechanism is disposed between the bottom circuit board and the top circuit board; A fixing mechanism is provided between the sensor body and the bottom circuit board; A heat dissipation structure is disposed between the sensor body and the underlying circuit board.

[0007] Preferably, both the top circuit board and the bottom circuit board are circular circuit boards, and the outer walls of both the top circuit board and the bottom circuit board are cut off on both sides.

[0008] Preferably, the heat dissipation structure includes: A sensor heat sink is disposed inside the sensor body; A heat dissipation through-hole is provided at the top of the bottom circuit board, and the sensor heat dissipation tube is inserted inside the heat dissipation through-hole.

[0009] Preferably, the fixing mechanism includes: Sensor pins, which are located inside the sensor body; The bottom plate sensor via is located at the top of the bottom circuit board. The bottom circuit board is soldered to the sensor pins through the bottom plate sensor vias. The contact surfaces of the outer wall of the bottom circuit board and the inner wall of the sensor body are coated with adhesive to avoid short circuits caused by the metal parts of the bottom circuit board contacting the metal shell of the sensor body, and to prevent the sensor pins from bending, being damaged and falling off due to repeated disassembly and shaking of the bottom circuit board by the top circuit board.

[0010] Preferably, the connecting mechanism includes: A 6-pin header is provided at the top of the bottom circuit board, and a first pin header slot is provided at the bottom of the top circuit board. The 6-pin header is positioned corresponding to the first pin header slot. A 4-pin header is provided at the top of the bottom circuit board, and a second pin slot is provided at the bottom of the top circuit board. The 4-pin header is positioned corresponding to the second pin slot. The bottom circuit board and the top circuit board are connected to the first pin header slot via a 6-pin header and to the second pin header slot via a 4-pin header.

[0011] Preferably, both the 6-pin header and the 4-pin header adopt a parallel header design so that the lead-out pins can communicate with each other on the multi-layer board. The installation and removal of the top board on the bottom board only requires plugging and unplugging.

[0012] Preferably, the bottom circuit board has a single-sided layout, and the top circuit board has a double-sided layout. The bottom circuit board is used for mounting sensitive devices, and the top circuit board is used for mounting heat-generating devices. The distance between the bottom circuit board and the top circuit board is greater than 7 mm to reduce heat radiation.

[0013] Preferably, the sensor body is a diffused silicon pressure sensor without hardware temperature compensation. The pressure transmitter adopts constant current drive or constant voltage drive, so that the sensor generates different voltage outputs under different pressures. The sensor includes a temperature sensing element. The variable pressure transmitter measures the sensor bridge output voltage reflecting the pressure magnitude and the ambient temperature reflecting the bridge resistance through two channels of the ADC, which are the pressure sampling value and temperature sampling value, respectively. The output characteristics of the transmitter and sensor as a whole are measured in different temperature ranges to find the extreme points of the slope change rate in the "pressure sampling value-temperature curve". These temperature points are used as the main temperature compensation target points.

[0014] Preferably, temperature compensation is performed in the high and low temperature chamber: the high and low temperature chamber is adjusted to the above target temperature point one by one, and pressure calibration is performed at several pressure points from zero to full at each temperature point. The sensor pressure sampling value at each pressure point is recorded, and the temperature sampling value at each target temperature point is recorded to form a "two-dimensional pressure sampling value-temperature table" and a "temperature and temperature sampling value linear table". Based on the "pressure sampling value-temperature curve," different degrees of compensation are applied to the curve characteristics of different compensation temperature ranges. For ranges with high nonlinearity, high-order polynomial fitting is used; for ranges with good linearity, quadratic fitting or linear fitting can be used.

[0015] Preferably, during the actual measurement process, the transmitter measures the real-time pressure output and temperature output. Using the temperature sampling value and the obtained temperature and temperature sampling value linear table, the position of the current temperature in the two-dimensional pressure-temperature table is found. Then, the fitting method selected for the temperature range is used to fit the "pressure value-pressure sampling value curve" of the actual temperature point. Finally, the current pressure value is obtained by using the pressure sampling value through linear interpolation.

[0016] The technical effects and advantages of this invention are as follows: This invention achieves effective isolation between sensitive and heat-generating devices through layered embedding of the bottom and top circuit boards, pluggable pin header connections, and a coordinated design of heat dissipation and fixing structures. This significantly reduces internal thermal coupling and mechanical interference. In applications using diffused silicon pressure sensors without hardware temperature compensation, this structure provides a more stable and controllable hardware environment for software-based temperature compensation algorithms, improving the consistency and repeatability of temperature and pressure sampling. Simultaneously, through a reasonable circuit board layout, heat dissipation channel design, and reliable fixing methods, it reduces pin stress and signal drift caused by temperature changes, vibration, and repeated assembly, enabling the transmitter to maintain stable operation over a wider ambient temperature range. This structure does not rely on complex hardware temperature compensation components, avoiding the limitations of traditional hardware temperature compensation methods in terms of compensation range, accuracy adjustment, and assembly space. Combined with software temperature compensation methods, it effectively expands the usable temperature range of the pressure transmitter and improves measurement accuracy across the entire temperature range, making it suitable for industrial applications requiring high reliability and wide temperature adaptability. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the split structure of the present invention. In the attached image:

[0018] 1. 6-pin header; 2. 4-pin header; 3. Sensor pins; 4. Sensor heat sink; 5. Heat dissipation through-hole; 6. Sensor via on base plate. Detailed Implementation

[0019] 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.

[0020] This invention provides, for example Figure 1 The transmitter circuit board connection structure of a diffused silicon pressure sensor shown includes a sensor body, a bottom circuit board, a top circuit board, a connecting mechanism, a fixing mechanism, and a heat dissipation structure. The bottom circuit board is embedded inside the sensor body, the top circuit board is embedded inside the sensor body and located above the bottom circuit board, the connecting mechanism is located between the bottom circuit board and the top circuit board, the fixing mechanism is located between the sensor body and the bottom circuit board, and the heat dissipation structure is located between the sensor body and the bottom circuit board. In the specific implementation process, the sensor body is a metal shell structure, which forms a cavity space for installing the transmitter circuit board. The bottom circuit board is installed in the cavity by embedding and forms a stable structural fit with the sensor body. It is used to support the sensitive signal processing device that is directly connected to the diffused silicon pressure sensor. The top circuit board is also embedded in the sensor body and is set above the bottom circuit board. It achieves electrical connection and signal interaction with the bottom circuit board through the connection mechanism, thus forming a layered circuit board layout structure. By setting a fixing mechanism between the sensor body and the bottom circuit board, the bottom circuit board is effectively constrained in both the axial and radial directions, avoiding displacement or stress concentration caused by vibration or external force during installation, transportation or long-term operation. At the same time, a heat dissipation structure is set between the sensor body and the bottom circuit board, so that the heat on the bottom circuit board can form an effective heat conduction path through the sensor body, thereby reducing the temperature rise of the circuit board and local areas of the sensor. The above structure achieves reliable electrical connection by arranging the bottom and top circuit boards in layers and combining them with a connection mechanism. While ensuring the overall compactness of the circuit, it effectively reduces thermal and mechanical interference between different functional components, improves the structural stability and operational reliability of the transmitter circuit under complex working conditions such as high temperature and vibration, and provides a good hardware foundation for the stable operation of subsequent pressure signal acquisition and temperature compensation algorithms.

[0021] Both the top and bottom circuit boards are circular circuit boards, and the outer walls of both the top and bottom circuit boards are cut on both sides. In the specific implementation process, both the top and bottom circuit boards adopt a circular board structure to match the cylindrical cavity inside the sensor body, which facilitates the coaxial installation and positioning of the circuit boards inside the sensor body. In order to adapt to the internal structure and internal space layout requirements of the sensor body, the outer walls of both the top and bottom circuit boards are set to be chamfered on both sides, so that the circular circuit boards can form flat edge areas locally while maintaining the overall structural strength. By setting two side-cutting structures on the outer periphery of the circular circuit board, the necessary assembly space can be reserved for the circuit board inside the sensor body, avoiding interference between the outer edge of the circuit board and the inner wall of the sensor body, and providing space for the arrangement of internal leads, fixing structures and heat dissipation channels. The aforementioned circular design, combined with the cut edges on both sides, achieves efficient use of internal space without increasing the overall size of the circuit board. This ensures the stability of the circuit board installation, reduces assembly difficulty, and improves the reliability of the transmitter's overall structure and the controllability of mass production.

[0022] The heat dissipation structure includes a sensor heat dissipation pipe 4 and a heat dissipation through hole 5. The sensor heat dissipation pipe 4 is located inside the sensor body, and the heat dissipation through hole 5 is opened at the top of the bottom circuit board. The sensor heat dissipation pipe 4 is inserted into the heat dissipation through hole 5. In the specific implementation process, the sensor heat sink 4 is arranged along the axial direction of the sensor body, and one end of it forms a good thermal contact with the sensor body so as to conduct the heat generated inside the sensor body to the outside. The top of the bottom circuit board is provided with a heat dissipation through hole 5 corresponding to the position of the sensor heat sink 4. The sensor heat sink 4 is inserted into the heat dissipation through hole 5, so that the heat dissipation through hole 5 and the sensor heat sink 4 form a through heat dissipation channel structure. By inserting the sensor heat pipe 4 into the heat dissipation through hole 5 of the bottom circuit board, the bottom circuit board can maintain a normal electrical layout while reserving a direct path for heat conduction, thereby avoiding the circuit board from blocking the heat conduction path. The heat generated on the bottom circuit board and the heat locally accumulated inside the sensor body can be quickly transferred to the sensor heat pipe 4 through the heat dissipation through hole 5, and further dissipated to the external environment through the sensor body. The above-mentioned heat dissipation structure forms an efficient heat dissipation path consisting of the bottom circuit board, heat dissipation through-hole 5 and sensor heat pipe 4 without increasing the number of additional heat dissipation devices. This effectively reduces the temperature rise inside the sensor and reduces the accumulation of heat near the bottom circuit board and sensitive device. This is beneficial to improving the measurement stability and reliability of the diffused silicon pressure sensor during long-term operation and provides a more stable thermal environment for subsequent temperature compensation algorithms.

[0023] The fixing mechanism includes sensor pin 3 and sensor through hole 6. The sensor pin 3 is located inside the sensor body, and the sensor through hole 6 is opened at the top of the bottom circuit board. The bottom circuit board is soldered to the sensor pin 3 through the bottom plate sensor via 6. The contact surfaces of the outer wall of the bottom circuit board and the inner wall of the sensor body are coated with glue to avoid short circuits caused by the metal part of the bottom circuit board contacting the metal shell of the sensor body, and to prevent the sensor pin 3 from bending, being damaged and falling off due to repeated disassembly and shaking of the bottom circuit board by the top circuit board. In the specific implementation process, the sensor body is provided with several sensor pins 3 inside. The sensor pins 3 are used to realize the electrical connection between the diffused silicon pressure sensor and the bottom circuit board. The bottom circuit board has a bottom plate sensor through hole 6 corresponding to the position of the sensor pins 3. The sensor pins 3 pass through the bottom plate sensor through hole 6 and are reliably electrically connected and mechanically fixed to the bottom circuit board by welding. After welding is completed, the contact area between the outer wall of the bottom circuit board and the inner wall of the sensor body is coated with adhesive to form a flexible support and buffer structure in the radial direction of the bottom circuit board. On the one hand, the adhesive layer can electrically isolate the metal edge of the bottom circuit board and avoid the risk of short circuit caused by direct contact between the bottom circuit board and the metal shell of the sensor body. On the other hand, after curing, the adhesive layer forms a fixed medium with a certain elasticity, which can absorb the small vibrations and displacements generated during assembly, transportation or operation. By combining welding and adhesive buffering, the bottom circuit board achieves a stable and reliable installation state inside the sensor body, effectively limiting the axial and radial shaking of the bottom circuit board. When the top circuit board is repeatedly plugged in or removed, the bottom circuit board can remain relatively stationary, thereby avoiding bending, fatigue, or desoldering of the sensor pins due to shaking, improving the reliability of electrical connections and the durability of the overall structure.

[0024] The connection mechanism includes a 6PIN header 1 and a 4PIN header 2. The 6PIN header 1 is located at the top of the bottom circuit board, and a first header slot is located at the bottom of the top circuit board. The 6PIN header 1 is positioned opposite to the first header slot. The 4PIN header 2 is located at the top of the bottom circuit board, and a second header slot is located at the bottom of the top circuit board. The 4PIN header 2 is positioned opposite to the second header slot. The bottom circuit board and the top circuit board are connected to the first pin header slot via 6-pin header 1 and the second pin header slot via 4-pin header 2; In the specific implementation process, the top of the bottom circuit board is provided with 6-pin headers and 4-pin headers respectively to realize the electrical connection between the bottom circuit board and the top circuit board. The bottom of the top circuit board is provided with a first pin header slot and a second pin header slot. The first pin header slot corresponds to the 6-pin header in terms of position and pin arrangement, and the second pin header slot corresponds to the 4-pin header in terms of position and pin arrangement. During assembly, the top-level circuit board is installed on the bottom-level circuit board from top to bottom. By aligning and inserting the first row of pin slots with the 6-pin header and simultaneously aligning and inserting the second row of pin slots with the 4-pin header, the top-level circuit board and the bottom-level circuit board complete the electrical connection of multiple signals and power in a single insertion operation. By using the insertion method of pin headers and pin slots, direct soldering between the bottom-level circuit board and the top-level circuit board is avoided, and the top-level circuit board can be disassembled by plugging and unplugging when maintenance or replacement is required. The aforementioned connection mechanism creates a stable, reliable, and repeatable electrical connection structure between the top and bottom circuit boards. While ensuring the integrity of multi-channel signal transmission, it effectively reduces assembly and maintenance difficulty. At the same time, the plug-in connection method reduces the risk of solder joint fatigue and damage caused by repeated soldering, which is conducive to improving the overall assembly consistency and long-term reliability of the transmitter circuit.

[0025] Among them, the 6PIN header 1 and the 4PIN header 2 both adopt a parallel header design so that the pins can be brought out and communicated with each other on the multi-layer board. The installation and removal of the top board on the bottom board only requires plugging and unplugging. In the specific implementation process, both 6PIN headers and 4PIN headers adopt a parallel header structure, with each pin arranged in parallel along the same direction and mounted on the bottom circuit board at a fixed interval, so that each pin has a stable and consistent geometric relationship. By adopting the parallel header design, multiple power signals, control signals and data signals can be led out simultaneously in a limited board space, realizing multi-channel communication connection between the bottom circuit board and the top circuit board. The top circuit board is plugged into the parallel pin header through the corresponding pin header slots. During assembly or maintenance, the installation and removal of the top circuit board on the bottom circuit board can be completed simply by inserting or pulling the top circuit board vertically. No additional soldering or disassembly of fasteners is required. This plug-in connection method makes the replacement and maintenance of the top circuit board more convenient and helps to shorten assembly and repair time. By using the parallel pin header and plug-in connection structure described above, the communication stability between multi-layer circuit boards is ensured, while the risk of mechanical stress and solder joint damage caused by repeated disassembly and assembly is reduced, thereby improving the reliability and maintainability of the circuit board connection structure. It is especially suitable for pressure transmitter applications that require multiple debugging or replacement of functional modules.

[0026] The bottom circuit board is a single-sided layout, while the top circuit board is a double-sided layout. The bottom circuit board is used for mounting sensitive devices, and the top circuit board is used for mounting heat-generating devices. The spacing between the bottom and top circuit boards is greater than 7 mm to reduce heat radiation. In the specific implementation process, the bottom circuit board adopts a single-sided layout to install sensitive devices and low-noise signal processing devices directly related to the diffused silicon pressure sensor. The single-sided layout reduces the number of wiring layers, reduces the possibility of parasitic parameters and mutual interference, and thus helps to improve the stability and consistency of pressure signal acquisition. The top circuit board adopts a double-sided layout, with the top and bottom sides used to arrange relatively high-power heat-generating devices and functional devices related to signal processing and communication. This allows the heat-generating devices to be concentrated in a position away from the sensor's sensitive area. By arranging the heat-generating devices and sensitive devices on different levels of the circuit board, the direct impact of heat sources on the diffused silicon pressure sensor and its front-end signal circuit can be effectively reduced. In addition, the mounting spacing between the bottom and top circuit boards is set to be greater than 7 mm, so that a stable air insulation space is formed between the two circuit boards, thereby reducing the impact of heat radiation and heat convection on the bottom circuit board. Through the combination of single-sided and double-sided layout and reasonable setting of board spacing, while ensuring the integration of circuit functions, the degree of internal thermal coupling is effectively reduced, and the measurement stability and long-term reliability of the pressure transmitter under different ambient temperature conditions are improved.

[0027] The sensor body is a diffused silicon pressure sensor without hardware temperature compensation. The pressure transmitter adopts constant current drive or constant voltage drive, so that the sensor generates different voltage outputs under different pressures. The sensor contains a temperature sensing element. The variable pressure transmitter measures the output voltage of the sensor bridge that reflects the pressure and the ambient temperature of the bridge resistance through two channels of the ADC. These are the pressure sampling value and the temperature sampling value, respectively. The overall output characteristics of the transmitter and sensor are measured in different temperature ranges to find the extreme points of the slope change rate in the "pressure sampling value-temperature curve". These temperature points are used as the main temperature compensation target points. In the specific implementation process, the main body of the sensor is a diffused silicon pressure sensor without hardware temperature compensation. It has a bridge structure for sensing pressure changes. The pressure transmitter uses constant current drive or constant voltage drive for the diffused silicon pressure sensor, so that the sensor generates a bridge output voltage that changes with the pressure magnitude under different pressures, as an analog signal reflecting the pressure magnitude. The diffused silicon pressure sensor also includes a temperature sensing element that is closely positioned within the bridge structure to reflect the temperature changes in the area where the bridge is located in real time. The pressure transmitter samples the output voltage of the bridge through two independent channels of the analog-to-digital conversion module to obtain the pressure sampling value, and samples the output signal of the temperature sensing element to obtain the temperature sampling value, thereby achieving synchronous acquisition of pressure and temperature information. During the compensation modeling stage, the pressure transmitter and diffused silicon pressure sensor were tested in multiple temperature ranges to obtain the output characteristic curve of the pressure sample value as a function of temperature. By analyzing the slope change of the pressure sample value-temperature curve in different temperature ranges, the location where the slope change rate reaches the extreme value was identified, and the corresponding temperature point was determined as the main temperature compensation target point for subsequent temperature compensation model establishment. Through the above implementation method, the selection of temperature compensation target points is based on the actual output characteristic changes of the sensor, rather than a simple equal-interval temperature division. This improves the compensation accuracy in the range where temperature characteristics change drastically and reduces unnecessary computational complexity in the range where temperature characteristics are relatively stable. This effectively improves the measurement accuracy and stability of diffused silicon pressure sensors without hardware temperature compensation over a wide temperature range.

[0028] Temperature compensation is performed in the high and low temperature chambers: the high and low temperature chambers are adjusted to the target temperature points one by one, and pressure calibration is performed at several pressure points from zero to full at each temperature point. The sensor pressure sampling values ​​at each pressure point are recorded, and the temperature sampling values ​​at each target temperature point are recorded to form a "two-dimensional pressure sampling value-temperature table" and a "temperature and temperature sampling value linear table". Based on the "pressure sampling value-temperature curve", different degrees of compensation are performed for the curve characteristics of different compensation temperature ranges. For ranges with large nonlinearity, high-order polynomial fitting is used, while for ranges with good linearity, quadratic fitting or linear fitting can be used. In the specific implementation process, during the temperature compensation modeling stage, the pressure transmitter and diffused silicon pressure sensor are placed in a high and low temperature chamber. By controlling the working state of the high and low temperature chamber, the internal ambient temperature is stabilized at each predetermined temperature compensation target point. At each target temperature point, after the sensor body, circuit board and internal temperature measuring element reach thermal equilibrium, several calibration pressure points are selected from zero to full scale, and standard pressure is applied point by point and pressure calibration is performed. During the calibration process, for each pressure calibration point, the corresponding sensor pressure sampling value is recorded, and the temperature sampling value at the target temperature point is also recorded. This establishes a two-dimensional pressure sampling value-temperature data table containing different temperature points and different pressure points. In addition, by recording the actual temperature and temperature sampling value at each target temperature point, a linear mapping relationship between temperature and temperature sampling value is established, forming a temperature-temperature sampling value linear table for subsequent real-time temperature positioning and conversion. After completing the above data collection, based on the characteristics of the pressure sample value-temperature curve obtained in the compensation modeling stage, different temperature compensation intervals are modeled separately. For temperature intervals where the pressure sample value shows obvious nonlinear characteristics with temperature change, a high-order polynomial fitting method is used to establish the pressure compensation model; for temperature intervals where the pressure sample value has good linearity with temperature change, a quadratic fitting or linear fitting method is used for modeling to reduce computational complexity while ensuring compensation accuracy. Through the above implementation method, by utilizing calibration data collected in a controlled environment using a high and low temperature chamber, and combining it with differentiated fitting strategies for different temperature ranges, a fine modeling of the temperature characteristics of a diffused silicon pressure sensor is achieved. This method can improve compensation accuracy in ranges with drastic temperature changes and reduce the risk of overfitting in ranges with stable temperature characteristics, thereby improving the overall measurement accuracy and stability of the pressure transmitter over a wide temperature range and providing a reliable data foundation for two-dimensional interpolation calculations in the real-time measurement stage.

[0029] In the actual measurement process, the transmitter measures the real-time pressure and temperature outputs. Using the temperature sampling values ​​and the obtained temperature and temperature sampling value linear table, the position of the current temperature in the two-dimensional pressure-temperature table is found. Then, the fitting method selected for the temperature range is used to fit the "pressure value-pressure sampling value curve" of the actual temperature point. Finally, the current pressure value is obtained by using the pressure sampling values ​​through linear interpolation. In the specific implementation process, when the pressure transmitter is in normal working condition, it collects the bridge output voltage of the diffused silicon pressure sensor and the output signal of the temperature sensing element inside the sensor in real time, and obtains the pressure sampling value and temperature sampling value through analog-to-digital conversion respectively. The temperature sampling value is used as a characterization parameter of the current working temperature and is used for positioning in the established temperature compensation data. During real-time compensation calculations, the actual temperature range corresponding to the current temperature sample value is first determined based on the mapping relationship between the temperature sample value and the temperature-temperature sample value linear table. Then, the calibration temperature point adjacent to this temperature range is located in the two-dimensional pressure sample value-temperature data table. Subsequently, according to the pre-selected fitting method for this temperature range, the pressure calibration data at the adjacent calibration temperature points are calculated and processed to generate a pressure value-pressure sample value relationship curve corresponding to the current actual temperature. After obtaining the relationship curve, the real-time collected pressure sampling values ​​are substituted into the relationship curve, and linear interpolation is used to calculate the pressure output corresponding to the current pressure sampling value. Through the above real-time measurement and compensation process, dynamic temperature compensation for the pressure measurement results is achieved. Through the above implementation method, the pressure transmitter can automatically match the most suitable compensation model based on the real-time operating temperature and perform accurate interpolation calculations in the two-dimensional pressure-temperature space, thereby avoiding the accuracy degradation problem caused by a single compensation model across the entire temperature range. This method significantly improves the accuracy and stability of pressure measurement under different temperature conditions while ensuring computational efficiency, and is suitable for high-precision measurement applications using diffused silicon pressure sensors without hardware temperature compensation.

[0030] 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 transmitter circuit board connection structure for a diffused silicon pressure sensor, characterized in that, include: Sensor body; The bottom circuit board is embedded inside the sensor body; A top-level circuit board, which is embedded inside the sensor body and located above the bottom-level circuit board; A connecting mechanism is disposed between the bottom circuit board and the top circuit board; A fixing mechanism is provided between the sensor body and the bottom circuit board; A heat dissipation structure is disposed between the sensor body and the underlying circuit board.

2. The transmitter circuit board connection structure of the diffused silicon pressure sensor according to claim 1, characterized in that, Both the top-layer circuit board and the bottom-layer circuit board are circular circuit boards, and the outer walls of both the top-layer circuit board and the bottom-layer circuit board are cut off on both sides.

3. The transmitter circuit board connection structure of the diffused silicon pressure sensor according to claim 1, characterized in that, The heat dissipation structure includes: The sensor heat sink (4) is located inside the sensor body; Heat dissipation through hole (5) is opened at the top of the bottom circuit board, and the sensor heat dissipation pipe (4) is inserted inside the heat dissipation through hole (5).

4. The transmitter circuit board connection structure of the diffused silicon pressure sensor according to claim 1, characterized in that, The fixing mechanism includes: Sensor pin (3), the sensor pin (3) is disposed inside the sensor body; The bottom plate sensor via (6) is located at the top of the bottom circuit board; The bottom circuit board is soldered to the sensor pin (3) through the bottom plate sensor through hole (6). The contact surfaces of the outer wall of the bottom circuit board and the inner wall of the sensor body are coated with glue to avoid short circuit caused by the metal part of the bottom circuit board contacting the metal shell of the sensor body, and to prevent the sensor (3) pin from bending, being damaged and falling off due to repeated disassembly and shaking of the bottom circuit board by the top circuit board.

5. The transmitter circuit board connection structure of the diffused silicon pressure sensor according to claim 1, characterized in that, The connecting mechanism includes: A 6PIN header (1) is provided at the top of the bottom circuit board, and a first header slot is provided at the bottom of the top circuit board. The 6PIN header (1) is positioned corresponding to the first header slot. 4PIN header (2), the 4PIN header (2) is disposed at the top of the bottom circuit board, and the bottom of the top circuit board is provided with a second header slot, the 4PIN header (2) and the second header slot are positioned corresponding to each other; The bottom circuit board and the top circuit board are connected to the first pin header slot via a 6-pin header (1) and to the second pin header slot via a 4-pin header (2).

6. The transmitter circuit board connection structure of the diffused silicon pressure sensor according to claim 5, characterized in that, Both the 6PIN header (1) and the 4PIN header (2) adopt a parallel header design so that the multi-layer boards can communicate with each other. The installation and removal of the top board on the bottom board only requires plugging and unplugging.

7. The transmitter circuit board connection structure of the diffused silicon pressure sensor according to claim 1, characterized in that, The bottom circuit board has a single-sided layout, and the top circuit board has a double-sided layout. The bottom circuit board is used for mounting sensitive devices, and the top circuit board is used for mounting heat-generating devices. The distance between the bottom circuit board and the top circuit board is greater than 7 mm to reduce heat radiation.

8. The transmitter circuit board connection structure of the diffused silicon pressure sensor according to claim 1, characterized in that, The sensor body is a diffused silicon pressure sensor without hardware temperature compensation. The pressure transmitter adopts constant current drive or constant voltage drive, so that the sensor generates different voltage outputs under different pressures. The sensor includes a temperature sensing element. The pressure transmitter measures the sensor bridge output voltage reflecting the pressure magnitude and the ambient temperature reflecting the bridge resistance through two channels of the ADC. These are the pressure sampling value and temperature sampling value, respectively. The output characteristics of the transmitter and sensor as a whole are measured in different temperature ranges to find the extreme points of the slope change rate in the "pressure sampling value-temperature curve". These temperature points are used as the main temperature compensation target points.

9. The transmitter circuit board connection structure of the diffused silicon pressure sensor according to claim 8, characterized in that, Temperature compensation is performed in the high and low temperature chamber: the high and low temperature chambers are adjusted to the target temperature points mentioned above one by one, and pressure calibration is performed at several pressure points from zero to full at each temperature point. The sensor pressure sampling values ​​at each pressure point are recorded, and the temperature sampling values ​​at each target temperature point are recorded to form a "two-dimensional pressure sampling value-temperature table" and a "temperature and temperature sampling value linear table". Based on the "pressure sampling value-temperature curve", different degrees of compensation are performed for the curve characteristics of different compensation temperature ranges. For ranges with large nonlinearity, high-order polynomial fitting is used, while for ranges with good linearity, quadratic fitting or linear fitting can be used.

10. The transmitter circuit board connection structure of the diffused silicon pressure sensor according to claim 9, characterized in that, In the actual measurement process, the transmitter measures the real-time pressure and temperature outputs. Using the temperature sampled values ​​and the obtained linear table of temperature and temperature sampled values, the position of the current temperature in the two-dimensional pressure-temperature table is found. Then, the fitting method selected for the temperature range is used to fit the "pressure value-pressure sampled value curve" of the actual temperature point. Finally, the current pressure value is obtained by using the pressure sampled values ​​through linear interpolation.

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