Sensors and electronics

Abstract

The application provides a sensor and an electronic device, the sensor comprising a circuit board, a first integrated sensor and a second integrated sensor, the first integrated sensor and the second integrated sensor are arranged on the circuit board, and a set temperature difference is formed between the working temperature of the second integrated sensor and the working temperature of the first integrated sensor to detect a target gas volume concentration and a water vapor volume concentration. The sensor of the application realizes real-time detection of temperature and air pressure and is used to quickly compensate the influence of humidity on the monitoring of the gas volume concentration, so as to ensure the detection sensitivity, detection accuracy and long-term stability of the sensor in detecting the target gas volume concentration and the water vapor volume concentration.

Description

Technical Field

[0001] This application belongs to the field of detection technology, specifically, it relates to a sensor and electronic device. Background Technology

[0002] With the widespread application of refrigeration and air conditioning systems, leak monitoring of refrigerant gases has become a critical aspect concerning personal safety, environmental protection, and reliable equipment operation. In particular, some newer refrigerants such as R32 and R454B, while possessing excellent energy efficiency, exhibit flammable, explosive, or weakly flammable properties. When these refrigerants accumulate in enclosed or semi-enclosed spaces and reach their lower explosive limit, they directly threaten life and property. Therefore, rapid, accurate, and real-time detection of such refrigerant leaks is of paramount importance.

[0003] In related technologies, capacitive sensors are used in the field of gas sensing for gas concentration detection. Their working principle is based on the change in dielectric constant caused by the adsorption of target gas by a sensitive dielectric material, which is then used to characterize the gas concentration through changes in capacitance. However, such sensors generally face severe cross-sensitivity interference problems. For example, when using polymers or metal oxides with selective gas adsorption properties as dielectric materials, these materials also have a strong affinity for water vapor. Fluctuations in ambient humidity can lead to competitive adsorption of water molecules, resulting in significant capacitance drift, thus affecting the sensor's detection sensitivity, accuracy, and long-term stability. Summary of the Invention

[0004] One objective of this application is to provide a new technical solution for sensors and electronic devices.

[0005] According to a first aspect of the embodiments of this application, a sensor is provided, the sensor comprising: Circuit board; A first integrated sensor and a second integrated sensor are both disposed on the circuit board, and a set temperature difference is formed between the operating temperature of the second integrated sensor and the operating temperature of the first integrated sensor to detect the target gas volume concentration and water vapor volume concentration.

[0006] Optionally, the set temperature difference is 5℃-50℃.

[0007] Optionally, the first integrated sensor and the second integrated sensor have the same structure.

[0008] Optionally, the first integrated sensor includes a first gas sensing unit and a first pressure sensing unit, and at least one of the first gas sensing unit and the first pressure sensing unit has a first temperature sensing unit. The second integrated sensor includes a second gas sensing unit and a second pressure sensing unit, and at least one of the second gas sensing unit and the second pressure sensing unit has a second temperature sensing unit.

[0009] Optionally, at least one of the first integrated sensor and the second integrated sensor is provided with a heating unit to create a set temperature difference between the operating temperature of the second integrated sensor and the operating temperature of the first integrated sensor.

[0010] Optionally, the sensitivity coefficients of the first integrated sensor to the target gas and humidity are aG1 and aH1, respectively. Within a set temperature range, aG1 decreases as the temperature increases, and aH1 increases as the temperature increases. The second integrated sensor has sensitivity coefficients of aG2 and aH2 for the target gas and humidity, respectively. Within a set temperature range, aG2 decreases as the temperature increases, while aH2 increases as the temperature increases.

[0011] Optionally, the output of the first integrated sensor is GS1, and the output of the second integrated sensor is GS2; GS1 = aG(T1,P)*c + aH(T1,P)*h GS2 = aG(T2,P)*c + aH(T2,P)*h Wherein, T1 is the operating temperature of the first integrated sensor, T2 is the operating temperature of the second integrated sensor, P is the ambient pressure of the first integrated sensor and the second integrated sensor, c is the target gas volume concentration, and h is the water vapor volume concentration.

[0012] Optionally, the changing trend of aG2 / aG1 is opposite to the changing trend of aH2 / aH1.

[0013] Optionally, the first gas sensing unit includes a first MEMS chip, the first MEMS chip includes a first electrode plate and a second electrode plate, a cavity is formed between the first electrode plate and the second electrode plate, the dielectric material in the cavity is gas, the first electrode plate is provided with a first vent hole, and the cavity is connected to the outside through the first vent hole.

[0014] According to a second aspect of the embodiments of this application, an electronic device is provided, the electronic device including the sensor described above.

[0015] One technical advantage of this application is: This application provides a sensor comprising a circuit board, a first integrated sensor, and a second integrated sensor. Both the first and second integrated sensors are mounted on the circuit board, and a set temperature difference is established between the operating temperatures of the second integrated sensor and the first integrated sensor to detect the target gas volume concentration and water vapor volume concentration. The sensor in this application provides real-time detection of temperature and air pressure and is used to quickly compensate for the influence of humidity on gas volume concentration monitoring, ensuring the sensor's detection sensitivity, accuracy, and long-term stability in detecting the target gas volume concentration and water vapor volume concentration.

[0016] Other features and advantages of this application will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the present application and, together with their description, serve to explain the principles of the present application.

[0018] Figure 1 This is a schematic diagram of the structure of a sensor provided in one embodiment of this application; Figure 2 A schematic diagram of the structure of a sensor provided in another embodiment of this application; Figure 3 This is a schematic diagram of a first integrated sensor structure provided in one embodiment of the present application; Figure 4 This is a schematic diagram of a first MEMS chip structure for a sensor provided in one embodiment of this application; Figure 5 A graph showing the characteristic of R32 gas and humidity sensitivity as a function of reference temperature T1, provided in one embodiment of this application; Figure 6 The graph shows the change of the gas and humidity sensitivity T2 / T1 heating ratio with reference temperature T1 as provided in one embodiment of this application.

[0019] in: 1. Circuit board; 2. First integrated sensor; 21. First gas sensing unit; 22. First pressure sensing unit; 211. First MEMS chip; 201. First electrode plate; 202. Second electrode plate; 203. First vent; 3. Second integrated sensor; 31. Second gas sensing unit; 32. Second pressure sensing unit; 4. Heating unit; 5. Control unit. Detailed Implementation

[0020] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0021] The embodiments of this application will now be described in detail, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0022] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0023] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0024] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0025] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0026] In related technologies, capacitive sensors are used in the field of gas sensing for gas concentration detection. Their working principle is based on the change in dielectric constant caused by the adsorption of target gas by a sensitive dielectric material, which is then used to characterize the gas concentration through changes in capacitance. However, such sensors generally face severe cross-sensitivity interference problems. For example, when using polymers or metal oxides with selective gas adsorption properties as dielectric materials, these materials also have a strong affinity for water vapor. Fluctuations in ambient humidity can lead to competitive adsorption of water molecules, resulting in significant capacitance drift, thus affecting the sensor's detection sensitivity, accuracy, and long-term stability.

[0027] The sensor provided in this application embodiment enables real-time detection of temperature and air pressure and is used to quickly compensate for the influence of humidity on gas volume concentration monitoring, ensuring the sensor's detection sensitivity, detection accuracy, and long-term stability in detecting target gas volume concentration and water vapor volume concentration.

[0028] Reference Figure 1 and Figure 2 This application provides a sensor, which includes: Circuit board 1; The first integrated sensor 2 and the second integrated sensor 3 are both mounted on the circuit board 1, and a set temperature difference is formed between the operating temperature of the second integrated sensor 3 and the operating temperature of the first integrated sensor 2, so as to detect the target gas volume concentration and water vapor volume concentration.

[0029] In the above embodiments, circuit board 1, as the basic supporting structure of the sensor, provides electrical connection and mechanical support for the first integrated sensor 2 and the second integrated sensor 3, ensuring the integrated layout of the two sensors and helping to reduce the overall size of the sensor. Simultaneously, circuit board 1 provides a channel for signal transmission between the first integrated sensor 2, the second integrated sensor 3, and the external control system, enabling real-time output of detection data.

[0030] See Figure 1 and Figure 2 The first integrated sensor 2, as the basic sensing unit in the detection array, can integrate a gas sensing unit and a pressure sensing unit to generate a capacitive response to the target gas and water vapor at a set operating temperature. Furthermore, the detection data from the first integrated sensor 2 can serve as a reference standard, providing basic data for the second integrated sensor 3 and the first integrated sensor 2 to separate the cross-sensitive signals of the target gas and water vapor through temperature difference comparison, thus achieving simultaneous detection of two parameters.

[0031] See Figure 1The second integrated sensor 3 and the first integrated sensor 2 are both mounted on the circuit board 1 but separated from each other. For example, a heat insulation structure can be used to separate the second integrated sensor 3 from the first integrated sensor 2, creating a set temperature difference between the operating temperatures of the second integrated sensor 3 and the first integrated sensor 2. For example, the operating temperature of the second integrated sensor 3 may be 10°C, 20°C, 30°C, or 40°C higher than that of the first integrated sensor 2. Since the adsorption / desorption characteristics of water vapor differ from those of the target gas at different temperatures, the capacitance change of the second integrated sensor 3 at different temperatures differs from that of the first integrated sensor 2. The capacitance difference between the two can effectively distinguish between water vapor interference and the target gas signal, thereby achieving decoupled detection of the target gas volume concentration and water vapor volume concentration, eliminating the capacitance drift problem caused by humidity cross-sensitivity, and improving detection sensitivity, detection accuracy, and long-term stability of the sensor.

[0032] This embodiment of the application establishes a temperature gradient between the second integrated sensor 3 and the first integrated sensor 2, creating a quantifiable difference in their responses to water vapor, while maintaining a relatively small difference in their responses to the target gas. By combining real-time temperature and pressure detection data with algorithmic compensation, the interference of water vapor on the capacitance value can be quickly separated, ensuring that the sensor can accurately output the true volume concentration of the target gas even in complex humidity environments. This effectively solves the detection drift problem caused by the competitive adsorption of water vapor in existing capacitive sensors.

[0033] The sensor provided in this embodiment includes a circuit board 1, a first integrated sensor 2, and a second integrated sensor 3. Both the first integrated sensor 2 and the second integrated sensor 3 are disposed on the circuit board 1, and a set temperature difference is formed between the operating temperature of the second integrated sensor 3 and the operating temperature of the first integrated sensor 2 to detect the target gas volume concentration and water vapor volume concentration. This sensor enables real-time detection of temperature and air pressure and is used to quickly compensate for the influence of humidity on gas volume concentration monitoring, ensuring the sensor's detection sensitivity, detection accuracy, and long-term stability in detecting the target gas volume concentration and water vapor volume concentration.

[0034] In one embodiment, both the first integrated sensor 2 and the second integrated sensor 3 can be formed on a substrate such as FR4, FR5, BT, glass, or ceramic using a PCB, and welded together with a metal cap to form an encapsulation cavity. A vent is opened on one side of the PCB or the metal cap, and a dustproof and waterproof mesh film is attached externally or internally. The MEMS chip and ASIC chip are connected to the PCB in the form of die-bond, wire-bond, or flip-chip.

[0035] In some embodiments, see Figure 1 and Figure 2 The circuit board 1 is equipped with a control unit 5. The first integrated sensor 2 and the second integrated sensor 3 are electrically connected to the control unit 5, so that the acquisition, processing and compensation calculation of the sensing signals are all completed on the same carrier, which improves the integration and response speed of the sensors. Moreover, based on the difference between the two signals and combined with the set temperature difference conditions, the control unit 5 can separate the target gas volume concentration and water vapor volume concentration through algorithm calculation, and use parameters such as temperature and air pressure to perform real-time compensation for humidity cross-sensitivity, and finally output the corrected high-precision detection result, ensuring the reliable operation of the dual-sensor differential compensation mechanism.

[0036] In addition, both the first integrated sensor 2 and the second integrated sensor 3 form MEMS capacitive gas sensors, avoiding the use of humidity sensors and realizing the miniaturization of the sensors.

[0037] In some embodiments, the temperature difference is set to 5℃-50℃, for example, the temperature difference is set to 10℃, 15℃, 20℃, 25℃, 30℃, 35℃, 40℃ or 45℃.

[0038] In the above embodiments, when the operating temperature difference between the second integrated sensor 3 and the first integrated sensor 2 is less than 5°C, the difference in the capacitive response of the first integrated sensor 2 and the second integrated sensor 3 to water vapor is too small, making it difficult to effectively distinguish between water vapor interference and target gas signals through differential operation; when the operating temperature difference between the second integrated sensor 3 and the first integrated sensor 2 exceeds 50°C, the large temperature difference will cause the adsorption characteristics of the sensitive dielectric material to change drastically, and may even cause material structure degradation, reducing detection accuracy and long-term stability.

[0039] In this embodiment, the operating temperature difference between the second integrated sensor 3 and the first integrated sensor 2 is limited to the range of 5℃-50℃. This ensures that the two sensors produce a sufficient and quantifiable difference in their response to water vapor, while maintaining the linear response characteristics of the sensitive material within its effective operating range. Thus, while ensuring the decoupling effect of water vapor, the detection sensitivity, detection accuracy, and long-term operational reliability of the sensors are also taken into account, achieving high-precision synchronous detection of the target gas volume concentration and water vapor volume concentration.

[0040] In some embodiments, the first integrated sensor 2 and the second integrated sensor 3 have the same structure.

[0041] In the above embodiments, the first integrated sensor 2 can integrate a gas sensing unit and a pressure sensing unit, and the second integrated sensor 3 can also integrate a gas sensing unit and a pressure sensing unit. The gas sensing unit and pressure sensing unit in the first integrated sensor 2 have the same structure as those in the second integrated sensor 3, so that the two sensors have the same response characteristics to the target gas and water vapor. This ensures that the signal difference between the first integrated sensor 2 and the second integrated sensor 3 comes only from the single variable of the set temperature difference, which simplifies the manufacturing process of the sensor, reduces production costs and consistency calibration difficulty, and provides a reliable foundation for subsequent accurate decoupling of water vapor and target gas based on dual-channel signal differential operation, ensuring high sensitivity, high accuracy and long-term stability of the sensor detection results.

[0042] In some embodiments, see Figures 1 to 3 The first integrated sensor 2 includes a first gas sensing unit 21 and a first pressure sensing unit 22, and at least one of the first gas sensing unit 21 and the first pressure sensing unit 22 has a first temperature sensing unit. The second integrated sensor 3 includes a second gas sensing unit 31 and a second pressure sensing unit 32, at least one of the second gas sensing unit 31 and the second pressure sensing unit 32 having a second temperature sensing unit.

[0043] In the above embodiment, the first gas sensing unit 21 in the first integrated sensor 2 senses the gas concentration by detecting the capacitance change caused by the adsorption of target gas and water vapor by a sensitive dielectric material; the first pressure sensing unit 22 can collect ambient air pressure data in real time. Integrating the first gas sensing unit 21 and the first pressure sensing unit 22 into the first integrated sensor 2 allows the sensor to simultaneously acquire ambient pressure parameters while outputting the gas response signal. This provides pressure compensation data for correcting the capacitance change to volume concentration, avoiding concentration conversion errors caused by air pressure fluctuations.

[0044] Furthermore, at least one of the first gas sensing unit 21 and the first pressure sensing unit 22 has a first temperature sensing unit, enabling the first integrated sensor 2 to acquire its own operating temperature in real time. Since the adsorption characteristics and capacitive response of the sensitive dielectric material are closely related to temperature, the temperature data collected by the first temperature sensing unit facilitates temperature compensation and water vapor decoupling calculations, thus balancing the functional integrity and structural simplicity of the first integrated sensor 2.

[0045] See Figure 1 and Figure 2The second gas sensing unit 31 of the second integrated sensor 3 generates a differential capacitance response to the target gas and water vapor under a set temperature difference; the second pressure sensing unit 32 works in conjunction with the first pressure sensing unit 22 to collect ambient air pressure in real time. In this embodiment, the second gas sensing unit 31 and the second pressure sensing unit 32 are integrated into the second integrated sensor 3, enabling the second integrated sensor 3 to possess both gas sensing and air pressure monitoring capabilities, providing complete environmental parameter input for the dual-channel differential compensation algorithm.

[0046] Furthermore, the inclusion of a second temperature sensing unit enables the second integrated sensor 3 to acquire its own operating temperature in real time. By combining the temperature data from the first integrated sensor 2 acquired by the first temperature sensing unit, the second temperature sensing unit can accurately calculate the actual temperature difference between the first integrated sensor 2 and the second integrated sensor 3, ensuring the accuracy and controllability of the set temperature difference. Simultaneously, the temperature data acquired by the second temperature sensing unit serves as another independent temperature input, cross-validating with the data from the first temperature sensing unit. This further enhances the accuracy and reliability of the temperature compensation calculation, thereby ensuring the sensitivity and accuracy of the decoupled detection of the target gas volume concentration and water vapor volume concentration.

[0047] In some embodiments, see Figure 1 and Figure 2 A heating unit 4 is provided on at least one of the first integrated sensor 2 and the second integrated sensor 3 so that a set temperature difference is formed between the operating temperature of the second integrated sensor 3 and the operating temperature of the first integrated sensor 2.

[0048] In the above embodiments, the operating temperature of the first integrated sensor 2 and / or the second integrated sensor 3 can be actively controlled by the heating unit 4, so that a stable and controllable temperature gradient is formed between the first integrated sensor 2 and the second integrated sensor 3; and the independence of the operating temperature of the first integrated sensor 2 and the second integrated sensor 3 can be ensured by means of heat insulation and temperature feedback devices.

[0049] In this embodiment, the active thermal management of the heating unit 4 precisely controls the temperature difference between the two integrated sensors to a set range of 5℃-50℃, so that the capacitive responses of the first integrated sensor 2 and the second integrated sensor 3 to water vapor produce a sufficient and quantifiable difference, while the response difference to the target gas is relatively controllable. This provides the control unit 5 with the conditions to separate the volume concentration of the target gas and the volume concentration of water vapor through dual-channel differential operation, eliminates the capacitive drift caused by humidity cross-sensitivity, and ensures detection sensitivity, detection accuracy and long-term stability.

[0050] In some embodiments, the sensitivity coefficients of the first integrated sensor 2 to the target gas and humidity are aG1 and aH1, respectively. Within a set temperature range, aG1 decreases as the temperature increases, while aH1 increases as the temperature increases. The second integrated sensor 3 has sensitivity coefficients of aG2 and aH2 for the target gas and humidity, respectively. Within the set temperature range, aG2 decreases as the temperature increases, while aH2 increases as the temperature increases.

[0051] In the above embodiments, aG1 decreases with increasing temperature, meaning the adsorption capacity of the target gas weakens at higher temperatures, resulting in a lower capacitive response. Conversely, aH1 increases with increasing temperature, indicating that the adsorption of water vapor increases at higher temperatures, leading to a stronger capacitive response. The opposite trends of aG1 and aH1 with temperature facilitate decoupling between water vapor and the target gas. For example, when a set temperature difference exists between the first integrated sensor 2 and the second integrated sensor 3, the difference in their responses to water vapor will be amplified, while the difference in their responses to the target gas will be relatively small. This provides a mathematical model basis for the control unit 5 to accurately separate the volume concentration of the target gas and the volume concentration of water vapor through dual-channel differential calculations, eliminating capacitive drift caused by humidity cross-sensitivity.

[0052] See Figure 5 The second integrated sensor 3 exhibits the same temperature response pattern as the first integrated sensor 2, meaning that the changing trends of aG2 and aG1, and aH2 and aH1, are consistent. The sensitivity coefficients of the first integrated sensor 2 and the second integrated sensor 3 are theoretically equal at the same temperature. Therefore, the differences between aG2 and aG1, and between aH2 and aH1, are caused only by the single variable of the set temperature difference, ensuring the physical consistency of the dual-sensor differential compensation mechanism. This allows the control unit 5 to accurately quantify and eliminate the influence of temperature on the sensitivity coefficient during decoupling operations, avoiding system errors introduced by individual sensor differences, and further improving the sensitivity and accuracy of detecting the target gas volume concentration and water vapor volume concentration.

[0053] See Figure 5 , Figure 5 This is a graph showing the characteristic of R32 gas and humidity sensitivity as a function of a reference temperature T1, provided in one embodiment of this application. Figure 5 The horizontal axis represents the reference temperature T1. The operating temperature T1 of the first integrated sensor 2 ranges from -40℃ to 80℃. After heating, the operating temperature of the second integrated sensor 3 is T2 = T1 + 20℃, which is used to compare the sensitivity change of the same sensor measurement point before and after heating. Figure 5The vertical axis includes a left vertical axis and a right vertical axis. The left vertical axis (Y-axis) represents the R32 refrigerant gas sensitivity unit au (the original amplitude of the analog signal) and the response value corresponding to each 1% lower explosive limit concentration; the right vertical axis (Y-axis) represents the humidity sensitivity unit au and the response value corresponding to each 1% relative humidity. From Figure 5 It can be seen that aH1 and aH2 increase almost exponentially with increasing temperature, while aG1 and aG2 decrease almost with increasing temperature. This inverse relationship can ensure the uniqueness and accuracy of the calculation of the target gas volume concentration c, water vapor volume concentration h, or humidity.

[0054] In some embodiments, the output of the first integrated sensor 2 is GS1, and the output of the second integrated sensor 3 is GS2; Formula 1: GS1 = aG(T1,P)*c + aH(T1,P)*h Formula 2: GS2 = aG(T2,P)*c + aH(T2,P)*h Where T1 is the operating temperature of the first integrated sensor 2, T2 is the operating temperature of the second integrated sensor 3, P is the ambient pressure of the first integrated sensor 2 and the second integrated sensor 3, c is the target gas volume concentration, and h is the water vapor volume concentration.

[0055] In the above embodiments, when both the target gas volume concentration c and the water vapor volume concentration h are relatively small, such as gas R32 concentration c < 7% = 50% LFL, or water vapor volume concentration h < 8% at 40℃-100%RH or 70℃-25%RH, the effect of the mixed gas on the dielectric constant of air can be considered to be linearly superimposed (the above operating conditions cover the actual situation of target gas leakage). However, operating at two different temperatures T1, T2 = T1 + The first integrated sensor 2 and the second integrated sensor 3 under T have significantly different sets of sensitivity coefficients, and are calibrated using the following formulas 3 and 4.

[0056] [aG(T1, P)|h=0, aH(T1, P)|c=0], Formula 3 [aG(T2, P)|h=0, aH(T2, P)|c=0], Formula 4 Calibrate aG when h=0 and aH when c=0. After calibrating the above set of sensitivity coefficients, it becomes two linear equations solving for two unknowns. This allows for the simultaneous, accurate, and rapid determination of the unique solution for the target gas volume concentration c and humidity h under any operating condition. For example, the target gas volume concentration c and water vapor volume concentration h can be accurately obtained within 1 second, eliminating the problems of cross-sensitivity and slow response of humidity sensors to gases. This enables real-time detection of temperature and air pressure, as well as rapid compensation for the target gas volume concentration.

[0057] In some embodiments, the changing trend of aG2 / aG1 is opposite to that of aH2 / aH1.

[0058] In the above embodiments, aG decreases with increasing temperature, and the ratio of aG2 / aG1 decreases monotonically with increasing temperature difference; while aH increases with increasing temperature, and the ratio of aH2 / aH1 increases monotonically with increasing temperature difference, with a large variation range. The changing trend of aG2 / aG1 is opposite to that of aH2 / aH1, meaning that as the set temperature difference increases, the coefficient ratios of c and h in the two equations show a separation trend of one decreasing and the other increasing. The condition number of the coefficient matrix of the equation system is continuously optimized, and the numerical stability of solving c and h is significantly enhanced. This indicates that the larger the temperature difference, the more significant the water vapor decoupling effect, the higher the accuracy of solving the target gas volume concentration c, and the smaller the solution error of the water vapor volume concentration h.

[0059] Meanwhile, the opposite trend of aG2 / aG1 to aH2 / aH1 provides a theoretical basis for limiting the set temperature difference to 5℃-50℃. Within the 5℃-50℃ range, the separation between aG2 / aG1 and aH2 / aH1 is sufficient to support high-precision decoupling. However, beyond this range, excessive decay of aG or excessive increase of aH will cause the linear response assumption to fail, instead introducing nonlinear errors.

[0060] Figure 6 This is a graph showing the change of the gas and humidity sensitivity T2 / T1 temperature rise ratio with reference temperature T1, provided in one embodiment of this application. Figure 6 The horizontal axis represents the operating temperature T1 of the first integrated sensor 2, and the operating temperature T2 of the second integrated sensor 3 is T1 + 20℃. Figure 6 The vertical axis represents the ratio of aG or aH sensitivity after heating to that before heating. Figure 6 It can be seen that aG2 / aG1 and aH2 / aH1 have significant differences within the set temperature range and do not appear in equal proportions, which can ensure the uniqueness and accuracy of the calculation of the target gas volume concentration c, water vapor volume concentration h, or humidity.

[0061] In some embodiments, see Figure 3 and Figure 4 The first gas sensing unit 21 includes a first MEMS chip 211. The first MEMS chip 211 includes a first electrode plate 201 and a second electrode plate 202. A cavity is formed between the first electrode plate 201 and the second electrode plate 202. The dielectric material in the cavity is gas. The first electrode plate 201 is provided with a first vent hole 203. The cavity is connected to the outside through the first vent hole 203.

[0062] In the above embodiments, the first MEMS chip 211, as a microelectromechanical system (MEMS) chip, can realize the gas sensing function in a chip-level integrated manner, so that the first gas sensing unit 21 has the advantages of small size, low power consumption and fast response. It is convenient to integrate the first MEMS chip 211 with the first pressure sensing unit 22, the first temperature sensing unit, etc. on the same circuit board 1, thereby improving the overall integration and reliability of the first integrated sensor 2.

[0063] See Figure 4 The first electrode 201 and the second electrode 202 form a parallel-plate capacitor structure. The cavity between the first electrode 201 and the second electrode 202 is the sensing area of ​​the capacitor, and the dielectric material is directly the external gas to be measured. When the target gas or water vapor molecules diffuse into the cavity through the first vent 203, their dielectric constant changes relative to the vacuum or reference gas, directly causing a change in the capacitance value between the first electrode 201 and the second electrode 202, thereby converting the gas concentration information into a measurable electrical signal. Using the gas itself as the dielectric material avoids the long-term drift problem caused by the aging of sensitive materials, which helps to ensure the long-term stability of the detection.

[0064] In this embodiment of the application, one or more first vent holes 203 are provided in the first electrode plate 201. The first vent holes 203 provide a diffusion channel for external gas molecules to enter the cavity, so that the dielectric material in the cavity can exchange with the external environment gas in real time, ensuring the real-time performance and accuracy of the sensing response.

[0065] In a specific embodiment, taking measured data of R32 gas as an example, such as at T1=20℃, T2=40℃, and a gas pressure of 1 atm, for simplification: aGi = aG(Ti,P) = aG(Ti,P)|h=0, aHi = aH(Ti,P) = aH(Ti,P)|c=0, where i=1,2.

[0066] If the coefficient ratio aG2 / aG1 ≠ aH2 / aH1 in Formula 1 and Formula 2, then the system of equations in Formula 1 and Formula 2 has a unique solution.

[0067] The measured values ​​were aG(20℃,Po)=52.8au / 1%LFL, aG(40℃,Po)48.2au / 1%LFL, aH(20℃,Po)75au / 1%RH, and aH(40℃,Po)93au / 1%RH.

[0068] In other words, Formula 1 and Formula 2 above can be expressed as follows: GS1 = 52.8 * c + 75 * h GS2 = 48.2 * c + 93 * h Therefore, it can be calculated that: c= (93*GS1-75*GS2) / (93*52.8-75*48.2) = (93*GS1- 75*GS2) / 1295 h = (GS1 - 52.8*c) / 75 The embodiments of this application solve two unknowns by using two linear equations, Formula 1 and Formula 2, which enables the simultaneous, accurate, and rapid determination of the unique solution for the target gas volume concentration c and humidity h under any operating condition. For example, the target gas volume concentration c and water vapor volume concentration h can be accurately obtained within 1 second, eliminating the problems of cross-sensitivity and slow response of humidity sensors to gases, thereby achieving real-time detection of temperature and air pressure and rapid compensation for the target gas volume concentration.

[0069] This application provides an electronic device that includes the aforementioned sensor.

[0070] While specific embodiments of this application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this application. The scope of this application is defined by the appended claims.

Claims

1. A sensor, characterized in that, include: Circuit board (1); The first integrated sensor (2) and the second integrated sensor (3) are both disposed on the circuit board (1), and the operating temperature of the second integrated sensor (3) and the operating temperature of the first integrated sensor (2) form a set temperature difference to detect the target gas volume concentration and water vapor volume concentration.

2. The sensor according to claim 1, characterized in that, The set temperature difference is 5℃-50℃.

3. The sensor according to claim 1, characterized in that, The first integrated sensor (2) and the second integrated sensor (3) have the same structure.

4. The sensor according to claim 1, characterized in that, The first integrated sensor (2) includes a first gas sensing unit (21) and a first pressure sensing unit (22), at least one of the first gas sensing unit (21) and the first pressure sensing unit (22) having a first temperature sensing unit; The second integrated sensor (3) includes a second gas sensing unit (31) and a second pressure sensing unit (32), at least one of the second gas sensing unit (31) and the second pressure sensing unit (32) having a second temperature sensing unit.

5. The sensor according to claim 1, characterized in that, A heating unit (4) is provided on at least one of the first integrated sensor (2) and the second integrated sensor (3) so that a set temperature difference is formed between the operating temperature of the second integrated sensor (3) and the operating temperature of the first integrated sensor (2).

6. The sensor according to claim 1, characterized in that, The sensitivity coefficients of the first integrated sensor (2) to the target gas and humidity are aG1 and aH1, respectively. Within the set temperature range, aG1 decreases as the temperature increases, and aH1 increases as the temperature increases. The second integrated sensor (3) has sensitivity coefficients of aG2 and aH2 for the target gas and humidity, respectively. Within the set temperature range, aG2 decreases as the temperature increases, and aH2 increases as the temperature increases.

7. The sensor according to claim 6, characterized in that, The output of the first integrated sensor (2) is GS1, and the output of the second integrated sensor (3) is GS2; GS1 = aG(T1,P)*c + aH(T1,P)*h GS2 = aG(T2,P)*c + aH(T2,P)*h Wherein, T1 is the operating temperature of the first integrated sensor (2), T2 is the operating temperature of the second integrated sensor (3), P is the environmental pressure of the first integrated sensor (2) and the second integrated sensor (3), c is the target gas volume concentration, and h is the water vapor volume concentration.

8. The sensor according to claim 6, characterized in that, The changing trend of aG2 / aG1 is opposite to the changing trend of aH2 / aH1.

9. The sensor according to claim 4, characterized in that, The first gas sensing unit (21) includes a first MEMS chip (211), the first MEMS chip (211) includes a first electrode plate (201) and a second electrode plate (202), a cavity is formed between the first electrode plate (201) and the second electrode plate (202), the dielectric material in the cavity is gas, the first electrode plate (201) is provided with a first vent hole (203), and the cavity is connected to the outside through the first vent hole (203).

10. An electronic device, characterized in that, Includes the sensor described in any one of claims 1-9.

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