Calibration method and device for pressure sensor

Abstract

The application relates to the technical field of pressure sensor calibration, in particular to a pressure sensor calibration method and device. The method comprises the following steps: collecting temperature variation data output by a pressure sensitive element in a pressure sensor under different temperatures and different pressure points, and simultaneously storing analog voltage values corresponding to the temperature variation data; calculating compensation parameters according to the temperature variation data, and inputting the compensation parameters into the pressure sensor; cutting off the connection between the pressure sensitive element and a signal conversion device in the pressure sensor, inputting the analog voltage values into the signal conversion device, and replacing the actual output of the pressure sensitive element to perform error checking; if the checking is qualified, restoring the connection between the pressure sensitive element and the signal conversion device, burning the compensation parameters, and completing the calibration. The application can solve the problems in the prior art, such as that the invariable temperature rechecking is unqualified at different temperature points, the variable temperature rechecking reduces the production efficiency and increases the production cost in the pressure sensor calibration process.

Description

Technical Field

[0001] This invention relates to the field of pressure sensor calibration technology, and in particular to a method and apparatus for calibrating a pressure sensor. Background Technology

[0002] In many fields such as industrial control, automotive electronics, and aerospace, pressure sensors serve as core detection components, and their measurement accuracy directly affects the stability and reliability of system operation. Temperature is a key factor affecting the performance of pressure sensors. During operation, sensors are prone to zero-point drift and sensitivity drift due to changes in ambient temperature, leading to measurement data deviations. Therefore, calibration and temperature compensation are necessary to offset the drift effects and ensure detection accuracy.

[0003] Currently in the industry, during the calibration process of pressure sensors, after collecting temperature variation data, compensation parameters are calculated. In order to verify the rationality of the compensation parameter calculation, two verification methods are mainly used: one is constant temperature retest, which directly tests the parameter effect at the current temperature; the other is variable temperature retest, which simulates different temperature environments to comprehensively test the pressure sensor to ensure that the parameters are applicable across the entire temperature range.

[0004] While constant-temperature retesting can save calibration time and improve efficiency, it cannot cover different temperature scenarios and there is a risk that the parameters will not meet the requirements at the actual operating temperature. While variable-temperature retesting can reduce the risk of non-compliance across the entire temperature range, it requires additional time to adjust the temperature, which prolongs the sensor production cycle and increases time and production costs. It is difficult to balance efficiency and reliability in both methods. Summary of the Invention

[0005] This invention provides a calibration method and apparatus for a pressure sensor, which solves the problems in the prior art where constant-temperature re-inspection fails at different temperature points and variable-temperature re-inspection reduces production efficiency and increases production costs during the pressure sensor calibration process.

[0006] In a first aspect, embodiments of the present invention provide a calibration method for a pressure sensor, comprising:

[0007] The system collects temperature change data output by the pressure-sensitive element in the pressure sensor at different temperatures and pressure points, and stores the analog voltage value corresponding to the temperature change data.

[0008] The compensation parameters are calculated based on the temperature variation data, and the compensation parameters are input into the pressure sensor;

[0009] Disconnect the pressure-sensitive element from the signal conversion device in the pressure sensor, and input the analog voltage value into the signal conversion device to perform error verification instead of the actual output of the pressure-sensitive element;

[0010] If the calibration is successful, the connection between the pressure-sensitive element and the signal conversion device is restored, and the compensation parameters are programmed to complete the calibration.

[0011] In one possible implementation, storing the analog voltage value corresponding to the temperature variation data includes:

[0012] The output voltage of the pressure-sensitive element is compared with the output voltage of the adjustable voltage device by a comparator. The control device adjusts the adjustable voltage device according to the comparison result. The control device acquires and stores the voltage value that is closest to the voltage output by the pressure-sensitive element at different temperatures and pressure points.

[0013] In one possible implementation, calculating compensation parameters based on the temperature variation data includes:

[0014] After adjusting the adjustable voltage device, the control device controls the multiplexer to connect the output voltage of the pressure-sensitive element to the signal conversion device. The host computer synchronously collects the original output data corresponding to the temperature change data at different temperatures and pressure points, and calculates compensation parameters based on the original output data.

[0015] In one possible implementation, disconnecting the pressure-sensitive element from the signal conversion device in the pressure sensor and inputting the analog voltage value into the signal conversion device includes:

[0016] The control device disconnects the pressure-sensitive element from the signal conversion device via a multiplexer, connects the output of the adjustable voltage device to the signal conversion device, and inputs the stored analog voltage values ​​into the signal conversion device sequentially according to the operating conditions.

[0017] In one possible implementation, error verification includes:

[0018] After receiving the analog voltage value, the signal conversion device performs analog-to-digital conversion and inputs it to the calibration and compensation device. The calibration and compensation device, in conjunction with the compensation parameters, performs temperature drift correction processing on the converted voltage value and outputs the corresponding digital signal.

[0019] The error is calculated by comparing the digital signal with the preset standard value under the corresponding working condition;

[0020] If the error is within the preset allowable range, the verification is deemed successful.

[0021] If the error is not within the preset allowable range, the verification is deemed unqualified.

[0022] In one possible implementation, after determining that the verification is unqualified if the error is not within the preset allowable range, the following steps are also included:

[0023] If the verification fails, proceed to the step of "calculate the compensation parameters based on the temperature change data and input the compensation parameters into the pressure sensor" to recalculate the compensation parameters;

[0024] If the second verification still fails, the process will jump to the step of "collecting the temperature change data output by the pressure-sensitive element in the pressure sensor at different temperatures and pressure points, and storing the analog voltage value corresponding to the temperature change data" and repeat the process until the verification is successful or an alarm is triggered.

[0025] In one possible implementation, if the verification is successful, restoring the connection between the pressure-sensitive element and the signal conversion device, and programming the compensation parameters to complete the calibration, includes:

[0026] If the verification is successful, the control device controls the multiplexer to re-establish the connection between the pressure-sensitive element and the signal conversion device, and controls the execution of the compensation parameter burning operation.

[0027] Secondly, embodiments of the present invention provide a calibration device for a pressure sensor, comprising: a pressure sensor and a host computer connected to the pressure sensor;

[0028] The host computer is used to collect temperature change data output by the pressure-sensitive element in the pressure sensor at different temperatures and pressure points, calculate compensation parameters based on the temperature change data, and input the compensation parameters into the pressure sensor.

[0029] The pressure sensor is used to simultaneously store the analog voltage value corresponding to the temperature change data during the acquisition of temperature change data; and to disconnect the connection between the pressure-sensitive element and the signal conversion device in the pressure sensor, input the analog voltage value into the signal conversion device to replace the actual output of the pressure-sensitive element for error verification; if the verification is qualified, the connection between the pressure-sensitive element and the signal conversion device is restored, and the compensation parameters are burned in to complete the calibration.

[0030] In one possible implementation, the pressure sensor includes: a pressure-sensitive element, an adjustable voltage device, a comparator, a control device, a multiplexer, a signal conversion device, a calibration and compensation device, and a storage device.

[0031] The input terminal of the comparator is connected to the output terminal of the pressure-sensitive element and the adjustable voltage device, respectively, and the output terminal of the comparator is connected to the input terminal of the control device;

[0032] The input terminal of the multiplexer is connected to the output terminal of the pressure-sensitive element and the adjustable voltage device, respectively; the control terminal of the multiplexer is connected to the output terminal of the control device; and the output terminal of the multiplexer is connected to the input terminal of the signal conversion device.

[0033] The output terminal of the signal conversion device is connected to the input terminal of the calibration compensation device, and the output terminal of the calibration compensation device is used to output the corresponding digital signal.

[0034] The control device is bidirectionally connected to the storage device, and the output terminal of the control device is also connected to the input terminal of the adjustable voltage device.

[0035] In one possible implementation, the signal conversion device is an AD conversion device.

[0036] This invention provides a calibration method and apparatus for a pressure sensor. The method involves collecting temperature-varying data output by the pressure-sensitive element in the pressure sensor at different temperatures and pressure points, and simultaneously storing the corresponding analog voltage values. Compensation parameters are calculated based on the temperature-varying data and input into the pressure sensor. The connection between the pressure-sensitive element and the signal conversion device in the pressure sensor is disconnected, and the analog voltage values ​​are input into the signal conversion device to perform error verification instead of the actual output of the pressure-sensitive element. If the verification is successful, the connection between the pressure-sensitive element and the signal conversion device is restored, and the compensation parameters are programmed to complete the calibration. This invention, through its technical feature of "collecting temperature-varying data at different temperature and pressure points and storing corresponding analog voltage values," pre-captures the output characteristics of the pressure sensor across its entire operating range. Furthermore, by employing the core design of "disconnecting the pressure-sensitive element and using the stored analog voltage value to replace the actual output for verification," it achieves "full-condition re-inspection without changing the temperature." This means that verification does not require readjusting the temperature environment; the stored analog voltage signal for all operating conditions is directly invoked. This comprehensively covers the verification scenarios at all target temperature points and completely eliminates the waiting time for secondary temperature changes. It achieves the effect of completing temperature-varying re-inspection without changing the temperature, improving sensor production efficiency, reducing the risk of failure at different temperature points, and indirectly increasing the yield of pressure sensors. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1This is a flowchart illustrating the implementation of the calibration method for a pressure sensor provided in an embodiment of the present invention.

[0039] Figure 2 This is a schematic diagram of the structure of the pressure sensor provided in an embodiment of the present invention;

[0040] Figure 3 This is a schematic diagram of the structure of the calibration device for the pressure sensor provided in an embodiment of the present invention. Detailed Implementation

[0041] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the invention. However, those skilled in the art will understand that the invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the invention with unnecessary detail.

[0042] To make the objectives, technical solutions, and advantages of the present invention clearer, specific embodiments will be described below in conjunction with the accompanying drawings.

[0043] Figure 1 The following is a detailed flowchart of a calibration method for a pressure sensor provided in an embodiment of the present invention:

[0044] Step 101: Collect the temperature change data output by the pressure-sensitive element in the pressure sensor at different temperatures and pressure points, and store the analog voltage value corresponding to the temperature change data.

[0045] Optional, see Figure 2 The diagram shows the structure of a pressure sensor, which includes: a pressure-sensitive element, an adjustable voltage device, a comparator, a control device, a multiplexer, a signal conversion device, a calibration and compensation device, and a storage device.

[0046] The input terminals of the comparator are connected to the output terminals of the pressure-sensitive element and the adjustable voltage device, respectively, and the output terminal of the comparator is connected to the input terminal of the control device.

[0047] The input terminals of the multiplexer are connected to the output terminals of the pressure-sensitive element and the adjustable voltage device, respectively; the control terminal of the multiplexer is connected to the output terminal of the control device; and the output terminal of the multiplexer is connected to the input terminal of the signal conversion device.

[0048] The output of the signal conversion device is connected to the input of the calibration and compensation device, and the output of the calibration and compensation device is used to output the corresponding digital signal.

[0049] The control device and the storage device are bidirectionally connected, and the output of the control device is also connected to the input of the adjustable voltage device.

[0050] This step is used to obtain Figure 2 The pressure sensor data shown provides a basis for subsequent error verification and compensation parameter calculation. The specific operation is as follows:

[0051] First, construct a test environment covering the target operating range: determine the different temperature conditions to be covered (including the expected operating temperature range of the pressure sensor), and select at least zero-point pressure, typical operating pressure point, and full-scale pressure point to form a combination of temperature and pressure test conditions; then, under each combination of test conditions, collect the temperature change data output by the pressure-sensitive element in the pressure sensor, and simultaneously store the analog voltage value corresponding to each set of temperature change data to establish a "temperature-pressure-analog voltage" correlation dataset, providing basic data support for subsequent error analysis and determination of compensation parameters.

[0052] In one embodiment, see Figure 2 As shown, storing the analog voltage values ​​corresponding to the temperature variation data can include:

[0053] The output voltage of the pressure-sensitive element is compared with the output voltage of the adjustable voltage device by a comparator. The control device adjusts the adjustable voltage device according to the comparison result, and obtains and stores the voltage value that is closest to the voltage output by the pressure-sensitive element at different temperatures and pressure points.

[0054] Under various temperature-pressure combination test conditions, the temperature variation data output by the pressure-sensitive element is stored according to the following method to obtain the corresponding analog voltage value:

[0055] First, the voltage signal output by the pressure-sensitive element under the current operating condition is connected to the first signal input terminal of the comparator, and the output voltage of the adjustable voltage device is connected to the second signal input terminal of the comparator.

[0056] Subsequently, the comparator compares the two input voltages in real time and feeds back the comparison results (such as voltage difference and level relationship) to the control device. Based on the comparison results, the control device dynamically adjusts the output voltage of the adjustable voltage device (for example, if the output voltage of the pressure-sensitive element is higher than the output voltage of the adjustable voltage device, the adjustable voltage device is controlled to increase its output voltage; if the former is lower than the latter, the adjustable voltage device is controlled to decrease its output voltage). The above adjustment operation is continuously executed until the output voltage of the adjustable voltage device and the current output voltage of the pressure-sensitive element reach a preset level of closeness (such as the voltage difference being less than a set accuracy threshold).

[0057] Finally, the control device acquires and stores the output voltage value of the adjustable voltage device at this time, and associates and binds the voltage value with the temperature variation data under the corresponding temperature and pressure conditions, thereby completing the construction of the "temperature-pressure-analog voltage" associated dataset.

[0058] Step 102: Calculate the compensation parameters based on the temperature variation data and input the compensation parameters into the pressure sensor.

[0059] In one embodiment, calculating compensation parameters based on temperature variation data may include:

[0060] After the adjustable voltage device is adjusted, the control device controls the multiplexer to connect the output voltage of the pressure-sensitive element to the signal conversion device. The host computer synchronously collects the original output data corresponding to the temperature change data at different temperatures and pressure points, and calculates the compensation parameters based on the original output data.

[0061] The core of this step is to determine the compensation parameters used to correct the pressure sensor error based on the temperature variation data obtained in step 101, and then configure them into the pressure sensor to provide a basis for correction in subsequent error verification.

[0062] Optionally, in this step, compensation parameters adapted to the pressure sensor are first calculated based on the "temperature-pressure-analog voltage" associated dataset. In one embodiment, the calculation process of these compensation parameters is specifically implemented as follows: First, after the adjustable voltage device is adjusted, that is, after the temperature data output by the pressure-sensitive element and the voltage value output by the adjustable voltage device reach a preset level of closeness, the control device sends a control signal to the multiplexer to control the multiplexer to switch the signal path and connect the output voltage of the pressure-sensitive element to the signal conversion device, so that the output voltage of the pressure-sensitive element can be converted into an electrical signal that can be recognized by the host computer through the signal conversion device. Subsequently, the host computer collects the original output data processed by the signal conversion device under the combined operating conditions of different temperatures and pressure points covered in step 101, and calculates compensation parameters (such as zero-point compensation coefficient, temperature compensation coefficient, gain compensation coefficient, etc.) for correcting problems such as zero-point offset, sensitivity deviation, and temperature drift of the pressure sensor by combining the operating condition variables of temperature and pressure.

[0063] After the compensation parameters are calculated, the calculated compensation parameters are input into the calibration compensation device of the pressure sensor to complete the pre-configuration of the compensation parameters in the pressure sensor, so as to provide a basis for correction parameters for subsequent error verification steps.

[0064] Step 103: Disconnect the pressure-sensitive element from the signal conversion device in the pressure sensor, and input the analog voltage value into the signal conversion device to perform error verification instead of the actual output of the pressure-sensitive element.

[0065] The core purpose of this step is to accurately verify the effectiveness of subsequent compensation parameters and the working accuracy of the signal conversion device by replacing the actual output of the pressure sensor with a simulated voltage signal, thus providing a controllable and traceable signal source basis for error verification.

[0066] In one embodiment, disconnecting the pressure-sensitive element from the signal conversion device in the pressure sensor and inputting the analog voltage value into the signal conversion device may include:

[0067] The control device disconnects the pressure-sensitive element from the signal conversion device via a multiplexer, connects the output of the adjustable voltage device to the signal conversion device, and inputs the stored analog voltage values ​​into the signal conversion device sequentially according to the operating conditions.

[0068] After the compensation parameters are calculated and input, the analog voltage value stored in step 101 is input to the signal conversion device in the following way:

[0069] First, the control device sends a control signal to the multiplexer, which then cuts off the signal connection between the pressure-sensitive element and the built-in signal conversion device of the pressure sensor. This ensures that the actual output voltage of the pressure-sensitive element no longer enters the signal conversion device, thus avoiding interference with the subsequent verification process.

[0070] Subsequently, after completing the above-mentioned disconnection operation, the control device continues to rebuild the signal path through the multiplexer, establishing a stable connection between the output terminal of the adjustable voltage device and the signal input terminal of the signal conversion device, so that the voltage signal output by the adjustable voltage device can be accurately transmitted to the signal conversion device, thus building a reliable transmission path for the input of the analog voltage value.

[0071] Finally, the control device retrieves the analog voltage values ​​stored in step 101 that correspond one-to-one with different temperature and pressure point combinations. According to the order of the test conditions carried out in step 101 (i.e., the same temperature-pressure combination sequence), the control device sends a control command to the adjustable voltage device, controlling the adjustable voltage device to output voltage signals consistent with the stored analog voltage values ​​in sequence. The voltage signals are input to the signal conversion device through the established path.

[0072] Through the above operations, the stored analog voltage value is used to replace the actual output voltage of the pressure-sensitive element under the corresponding operating conditions. Subsequently, based on the processing results of the standard analog voltage signal in the signal conversion device, error verification can be carried out to determine whether the compensation parameter can effectively correct the error. At the same time, it can also verify whether the conversion accuracy of the signal conversion device itself meets the requirements.

[0073] In one embodiment, error verification may include:

[0074] After receiving the analog voltage value, the signal conversion device performs analog-to-digital conversion and inputs it to the calibration and compensation device. The calibration and compensation device, in conjunction with the compensation parameters, performs temperature drift correction processing on the voltage value after analog-to-digital conversion and outputs the corresponding digital signal.

[0075] The error is calculated by comparing the digital signal with the preset standard value under the corresponding working condition;

[0076] If the error is within the preset allowable range, the verification is deemed successful.

[0077] If the error is not within the preset allowable range, the verification is deemed unqualified.

[0078] After the analog voltage value is input into the signal conversion device, the core execution stage of error verification begins. Through signal processing, error calculation and verification, the effectiveness of the compensation parameters and the overall accuracy of the pressure sensor are finally verified.

[0079] Optional, see Figure 2 After receiving the input analog voltage value, the signal conversion device performs analog-to-digital conversion to obtain the voltage value, which is then sent to the calibration and compensation device. The calibration and compensation device immediately calls upon the compensation parameters (including core parameters such as the temperature compensation coefficient) pre-configured in the pressure sensor to perform targeted temperature drift correction processing on the voltage value obtained from the analog-to-digital conversion. Since the analog voltage value corresponds to different temperature-pressure combinations, the temperature drift correction processing can accurately offset the interference of temperature changes on the signal, ensuring the accuracy of signal processing; after temperature drift correction, the digital signal is output.

[0080] After receiving the digital signal, the control device or host computer accurately matches the temperature-pressure combination operating condition corresponding to the digital signal and retrieves the pre-set standard value under the operating condition (the standard value is the ideal value that the pressure sensor should output under the corresponding operating condition, determined based on theoretical calculations and standard calibration data); then, using a preset error calculation algorithm (such as absolute error, relative error, etc.), the difference between the currently output digital signal and the matched preset standard value is calculated to obtain the error.

[0081] The calculated error is compared with the preset error allowable range to determine the verification result: if the error is within the preset allowable range, it means that the compensation parameter can effectively correct the sensor error and the accuracy of the pressure sensor under this working condition meets the requirements, and the verification is deemed qualified; if the error is not within the preset allowable range, it means that the correction effect of the compensation parameter has not met expectations, or the sensor has other accuracy problems, and the verification is deemed unqualified. The compensation parameter needs to be re-optimized and the verification process needs to be carried out again.

[0082] After determining that the verification is unqualified if the error is not within the preset allowable range, the following steps are also included:

[0083] If the verification fails, jump to the step of "calculating compensation parameters based on the temperature-variable data and inputting the compensation parameters into the pressure sensor" to recalculate the compensation parameters.

[0084] If the secondary verification still fails, jump to the step of "collecting the temperature-variable data output by the pressure-sensitive element in the pressure sensor at different temperatures and different pressure points, and simultaneously storing the analog voltage values corresponding to the temperature-variable data" to execute again until the verification is qualified or an alarm is given.

[0085] Optionally, if the first verification fails, it may be a problem with calculating the compensation parameters. Therefore, re-optimize the compensation parameters. For example, recalculate the compensation parameters using other preset methods, and then perform verification based on the subsequent steps. If the secondary verification still fails, it may be a problem with the temperature-variable data collected in step 101. Therefore, jump to step 101 to execute again. If the verification still fails, it may be a problem with the pressure sensor itself. At this moment, the upper computer can give an alarm.

[0086] Step 104, if the verification is qualified, restore the connection between the pressure-sensitive element and the signal conversion device, and perform the burning of the compensation parameters to complete the calibration.

[0087] When the error verification is determined to be qualified, it indicates that the pre-configured compensation parameters can effectively guarantee the output accuracy of the pressure sensor under the target working conditions. At this time, enter the final stage of the calibration process. Complete the final calibration by restoring the signal path and burning the compensation parameters. The specific process is as follows:

[0088] The control device sends a path switching instruction to the multiplexer, instructing the multiplexer to disconnect the connection between the adjustable voltage device and the signal conversion device, and simultaneously re-establish the signal transmission path between the pressure-sensitive element and the signal conversion device. This operation can make the pressure sensor return to the normal working state, ensuring that in subsequent actual applications, the signal output by the pressure-sensitive element can be accurately transmitted to the calibration compensation device for processing.

[0089] After the path restoration is completed, the control device or the upper computer sends a burning instruction to the storage module (such as a non-volatile memory) of the pressure sensor, and permanently burns the verified compensation parameters (including zero-point compensation coefficient, temperature compensation coefficient, gain compensation coefficient, etc.) into the storage module. The burning process needs to ensure the integrity and accuracy of the parameter writing, avoiding the calibration effect from being invalid due to parameter loss or error. After the burning is completed, the storage module can automatically call the compensation parameters when the sensor is powered on to work, realizing real-time and accurate correction of the output signal.

[0090] This invention provides a calibration method for a pressure sensor. The method involves collecting temperature-varying data output by the pressure-sensitive element at different temperatures and pressure points, and simultaneously storing the corresponding analog voltage values. Compensation parameters are calculated based on the temperature-varying data and input into the pressure sensor. The connection between the pressure-sensitive element and the signal conversion device in the pressure sensor is disconnected, and the analog voltage values ​​are input into the signal conversion device to perform error verification instead of the actual output of the pressure-sensitive element. If the verification is successful, the connection between the pressure-sensitive element and the signal conversion device is restored, and the compensation parameters are programmed to complete the calibration. This invention, through its technical feature of "collecting temperature-varying data at different temperature and pressure points and storing corresponding analog voltage values," pre-captures the output characteristics of the pressure sensor across its entire operating range. Furthermore, by employing the core design of "disconnecting the pressure-sensitive element and using the stored analog voltage value to replace the actual output for verification," it achieves "full-condition re-inspection without changing the temperature." This means that verification does not require readjusting the temperature environment; the stored analog voltage signal for all operating conditions is directly invoked. This comprehensively covers the verification scenarios at all target temperature points and completely eliminates the waiting time for secondary temperature changes. It achieves the effect of completing temperature-varying re-inspection without changing the temperature, improving sensor production efficiency, reducing the risk of non-compliance at different temperature points, and indirectly increasing the yield of pressure sensors. This perfectly resolves the contradiction between "risk control" and "efficiency improvement" in traditional technologies.

[0091] In this embodiment of the invention, compensation parameters are calculated based on variable temperature data. This ensures that the compensation parameters are derived from the temperature drift characteristics under all operating conditions, accurately matching the error patterns under different temperature and pressure combinations, rather than being generalized parameters. During subsequent verification, the design of "simulated voltage values ​​replacing actual outputs" requires that the compensation parameters be verified one by one under all stored temperature and pressure conditions—the simulated voltage value is strongly bound to the corresponding temperature and pressure condition, equivalent to recreating the real working scenario at each temperature point, effectively identifying the potential for "parameter mismatch failure at a certain temperature point." This process allows the effectiveness of the compensation parameters to be verified from all dimensions, significantly reducing the risk of sensor failure in actual use due to temperature drift, and indirectly improving the yield rate.

[0092] This invention employs a closed-loop technology of "data acquisition - parameter calculation - alternative verification - successful programming" to form a standardized process: During data acquisition, all operating condition information is stored in one go; during verification, no additional temperature adjustments or operating condition changes are required, and full-dimensional verification can be completed simply by switching signal paths using a multiplexer; after successful verification, the connection is directly restored and parameters are programmed, resulting in a seamless process without redundant steps. This design reduces the complexity of manual intervention and operating condition adjustments, shortens the calibration cycle of a single sensor, significantly improves production efficiency, and facilitates integration with automated equipment, making it suitable for industrial mass production scenarios.

[0093] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0094] The following are device embodiments of the present invention. For details not described in detail, please refer to the corresponding method embodiments described above.

[0095] Figure 3 A schematic diagram of a pressure sensor calibration device according to an embodiment of the present invention is shown. For ease of explanation, only the parts related to the embodiment of the present invention are shown, and are described in detail below:

[0096] like Figure 3 As shown, the calibration device for the pressure sensor includes a pressure sensor 31 and a host computer 32 connected to the pressure sensor 31.

[0097] The host computer 32 is used to collect the temperature change data output by the pressure sensing element in the pressure sensor 31 at different temperatures and pressure points, calculate the compensation parameters based on the temperature change data, and input the compensation parameters into the pressure sensor.

[0098] Pressure sensor 31 is used to simultaneously store the analog voltage value corresponding to the temperature change data during the acquisition of temperature change data; and to disconnect the connection between the pressure sensitive element and the signal conversion device in the pressure sensor, input the analog voltage value into the signal conversion device to replace the actual output of the pressure sensitive element for error verification; if the verification is qualified, the connection between the pressure sensitive element and the signal conversion device is restored, and the compensation parameters are burned in to complete the calibration.

[0099] In one possible implementation, such as Figure 2 As shown, the pressure sensor 31 includes: a pressure-sensitive element, an adjustable voltage device, a comparator, a control device, a multiplexer, a signal conversion device, a calibration and compensation device, and a storage device.

[0100] The input terminals of the comparator are connected to the output terminals of the pressure-sensitive element and the adjustable voltage device, respectively, and the output terminal of the comparator is connected to the input terminal of the control device.

[0101] The input terminals of the multiplexer are connected to the output terminals of the pressure-sensitive element and the adjustable voltage device, respectively; the control terminal of the multiplexer is connected to the output terminal of the control device; and the output terminal of the multiplexer is connected to the input terminal of the signal conversion device.

[0102] The output of the signal conversion device is connected to the input of the calibration and compensation device, and the output of the calibration and compensation device is used to output the corresponding digital signal.

[0103] The control device and the storage device are bidirectionally connected, and the output of the control device is also connected to the input of the adjustable voltage device.

[0104] The signal conversion device is an AD converter.

[0105] In one possible implementation, a comparator compares the output voltage of the pressure-sensitive element with the output voltage of the adjustable voltage device, and the control device adjusts the adjustable voltage device according to the comparison result; and acquires and stores the voltage value that is closest to the voltage output by the pressure-sensitive element at different temperatures and pressure points.

[0106] In one possible implementation, after the adjustable voltage device is adjusted, the control device controls the multiplexer to connect the output voltage of the pressure-sensitive element to the signal conversion device. The host computer synchronously collects the original output data corresponding to the temperature change data at different temperatures and pressure points, and calculates the compensation parameters based on the original output data.

[0107] In one possible implementation, disconnecting the pressure-sensitive element from the signal conversion device in the pressure sensor and inputting the analog voltage value into the signal conversion device includes:

[0108] The control device disconnects the pressure-sensitive element from the signal conversion device via a multiplexer, connects the output of the adjustable voltage device to the signal conversion device, and inputs the stored analog voltage values ​​into the signal conversion device sequentially according to the operating conditions.

[0109] In one possible implementation, error verification includes:

[0110] After receiving the analog voltage value, the signal conversion device performs analog-to-digital conversion and inputs it to the calibration and compensation device. The calibration and compensation device, in conjunction with the compensation parameters, performs temperature drift correction processing on the voltage value after analog-to-digital conversion and outputs the corresponding digital signal.

[0111] The error is calculated by comparing the digital signal with the preset standard value under the corresponding working condition;

[0112] If the error is within the preset allowable range, the verification is deemed successful.

[0113] If the error is not within the preset allowable range, the verification is deemed unqualified.

[0114] In one possible implementation, after determining that the verification is unqualified if the error is not within the preset allowable range, the following steps are also included:

[0115] If the verification fails, proceed to the step of "Calculate the compensation parameters based on the temperature change data and input the compensation parameters into the pressure sensor" to recalculate the compensation parameters;

[0116] If the second verification still fails, the process will jump to the step of "collecting the temperature change data output by the pressure-sensitive element in the pressure sensor at different temperatures and pressure points, and storing the analog voltage value corresponding to the temperature change data" and repeat the process until the verification is successful or an alarm is triggered.

[0117] In one possible implementation, if the verification is successful, the connection between the pressure-sensitive element and the signal conversion device is restored, and the compensation parameters are programmed to complete the calibration, including:

[0118] If the verification is successful, the control device controls the multiplexer to re-establish the connection between the pressure-sensitive element and the signal conversion device, and controls the execution of the compensation parameter burning operation.

[0119] The above embodiment provides a calibration device for a pressure sensor. A host computer collects temperature-varying data output by the pressure-sensitive element in the pressure sensor at different temperatures and pressure points, calculates compensation parameters based on the temperature-varying data, and inputs the compensation parameters into the pressure sensor. The pressure sensor simultaneously stores the analog voltage value corresponding to the temperature-varying data during the data acquisition process. The device also disconnects the pressure-sensitive element from the signal conversion device in the pressure sensor, inputs the analog voltage value into the signal conversion device to perform error verification instead of the actual output of the pressure-sensitive element. If the verification is successful, the connection between the pressure-sensitive element and the signal conversion device is restored, and the compensation parameters are programmed to complete the calibration. This invention, through its technical feature of "collecting temperature-varying data at different temperature and pressure points and storing corresponding analog voltage values," pre-captures the output characteristics of the pressure sensor across its entire operating range. Furthermore, by employing the core design of "disconnecting the pressure-sensitive element and using the stored analog voltage value to replace the actual output for verification," it achieves "full-condition re-inspection without changing the temperature." This means that verification does not require readjusting the temperature environment; the stored analog voltage signal for all operating conditions is directly invoked. This comprehensively covers the verification scenarios at all target temperature points and completely eliminates the waiting time for secondary temperature changes. It achieves the effect of completing temperature-varying re-inspection without changing the temperature, improving sensor production efficiency, reducing the risk of non-compliance at different temperature points, and indirectly increasing the yield of pressure sensors. This perfectly resolves the contradiction between "risk control" and "efficiency improvement" in traditional technologies.

[0120] In this embodiment of the invention, compensation parameters are calculated based on variable temperature data. This ensures that the compensation parameters are derived from the temperature drift characteristics under all operating conditions, accurately matching the error patterns under different temperature and pressure combinations, rather than being generalized parameters. During subsequent verification, the design of "simulated voltage values ​​replacing actual outputs" requires that the compensation parameters be verified one by one under all stored temperature and pressure conditions—the simulated voltage value is strongly bound to the corresponding temperature and pressure condition, equivalent to recreating the real working scenario at each temperature point, effectively identifying the potential for "parameter mismatch failure at a certain temperature point." This process allows the effectiveness of the compensation parameters to be verified from all dimensions, significantly reducing the risk of sensor failure in actual use due to temperature drift, and indirectly improving the yield rate.

[0121] This invention employs a closed-loop technology of "data acquisition - parameter calculation - alternative verification - successful programming" to form a standardized process: During data acquisition, all operating condition information is stored in one go; during verification, no additional temperature adjustments or operating condition changes are required, and full-dimensional verification can be completed simply by switching signal paths using a multiplexer; after successful verification, the connection is directly restored and parameters are programmed, resulting in a seamless process without redundant steps. This design reduces the complexity of manual intervention and operating condition adjustments, shortens the calibration cycle of a single sensor, significantly improves production efficiency, and facilitates integration with automated equipment, making it suitable for industrial mass production scenarios.

[0122] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A calibration method for a pressure sensor, characterized in that, include: The system collects temperature change data output by the pressure-sensitive element in the pressure sensor at different temperatures and pressure points, and stores the analog voltage value corresponding to the temperature change data. Storing the analog voltage value corresponding to the temperature variation data includes: comparing the output voltage of the pressure-sensitive element with the output voltage of the adjustable voltage device using a comparator, and adjusting the adjustable voltage device by a control device according to the comparison result; acquiring and storing the voltage value closest to the voltage output by the pressure-sensitive element at different temperatures and pressure points. The compensation parameters are calculated based on the temperature variation data, and the compensation parameters are input into the pressure sensor; Disconnecting the pressure-sensitive element from the signal conversion device in the pressure sensor, and inputting the analog voltage value into the signal conversion device to perform error verification instead of the actual output of the pressure-sensitive element; includes: the control device disconnecting the pressure-sensitive element from the signal conversion device via a multiplexer, connecting the output terminal of the adjustable voltage device to the signal conversion device, and sequentially inputting the stored analog voltage values ​​into the signal conversion device according to the operating condition sequence; If the calibration is successful, the connection between the pressure-sensitive element and the signal conversion device is restored, and the compensation parameters are programmed to complete the calibration.

2. The calibration method for a pressure sensor according to claim 1, characterized in that, The compensation parameters are calculated based on the temperature variation data, including: After the adjustable voltage device is adjusted, the control device controls the multiplexer in the pressure sensor to connect the output voltage of the pressure-sensitive element to the signal conversion device. The host computer synchronously collects the original output data corresponding to the temperature change data at different temperatures and pressure points, and calculates compensation parameters based on the original output data.

3. The calibration method for a pressure sensor according to claim 2, characterized in that, Error verification includes: After receiving the analog voltage value, the signal conversion device performs analog-to-digital conversion and inputs it to the calibration and compensation device. The calibration and compensation device, in conjunction with the compensation parameters, performs temperature drift correction processing on the converted voltage value and outputs the corresponding digital signal. The error is calculated by comparing the digital signal with the preset standard value under the corresponding working condition; If the error is within the preset allowable range, the verification is deemed successful. If the error is not within the preset allowable range, the verification is deemed unqualified.

4. The calibration method for a pressure sensor according to claim 3, characterized in that, After determining that the verification is unqualified if the error is not within the preset allowable range, the following steps are also included: If the verification fails, proceed to the step of "calculate the compensation parameters based on the temperature change data and input the compensation parameters into the pressure sensor" to recalculate the compensation parameters; If the second verification still fails, the process will jump to the step of "collecting the temperature change data output by the pressure-sensitive element in the pressure sensor at different temperatures and pressure points, and storing the analog voltage value corresponding to the temperature change data" and repeat the process until the verification is successful or an alarm is triggered.

5. The calibration method for a pressure sensor according to claim 4, characterized in that, If the verification is successful, the connection between the pressure-sensitive element and the signal conversion device is restored, and the compensation parameters are programmed to complete the calibration, including: If the verification is successful, the control device controls the multiplexer to re-establish the connection between the pressure-sensitive element and the signal conversion device, and controls the execution of the compensation parameter burning operation.

6. A calibration device for a pressure sensor, characterized in that, include: A pressure sensor and a host computer connected to the pressure sensor; The host computer is used to collect temperature change data output by the pressure-sensitive element in the pressure sensor at different temperatures and pressure points, calculate compensation parameters based on the temperature change data, and input the compensation parameters into the pressure sensor. The pressure sensor is used to simultaneously store the analog voltage value corresponding to the temperature change data during the process of acquiring temperature change data. And disconnect the pressure-sensitive element from the signal conversion device in the pressure sensor, and input the analog voltage value into the signal conversion device to perform error verification instead of the actual output of the pressure-sensitive element; If the calibration is successful, the connection between the pressure-sensitive element and the signal conversion device is restored, and the compensation parameters are programmed to complete the calibration. The pressure sensor includes: a pressure-sensitive element, an adjustable voltage device, a comparator, a control device, a multiplexer, a signal conversion device, a calibration and compensation device, and a storage device; The input terminal of the comparator is connected to the output terminal of the pressure-sensitive element and the adjustable voltage device, respectively, and the output terminal of the comparator is connected to the input terminal of the control device; The input terminal of the multiplexer is connected to the output terminal of the pressure-sensitive element and the adjustable voltage device, respectively; the control terminal of the multiplexer is connected to the output terminal of the control device; and the output terminal of the multiplexer is connected to the input terminal of the signal conversion device. The output terminal of the signal conversion device is connected to the input terminal of the calibration compensation device, and the output terminal of the calibration compensation device is used to output the corresponding digital signal. The control device is bidirectionally connected to the storage device, and the output terminal of the control device is also connected to the input terminal of the adjustable voltage device; The output voltage of the pressure-sensitive element is compared with the output voltage of the adjustable voltage device using a comparator. The control device adjusts the adjustable voltage device according to the comparison result. The control device acquires and stores the voltage value that is closest to the voltage output by the pressure-sensitive element at different temperatures and pressure points. The control device disconnects the pressure-sensitive element from the signal conversion device via a multiplexer, connects the output of the adjustable voltage device to the signal conversion device, and inputs the stored analog voltage values ​​into the signal conversion device sequentially according to the operating conditions.

7. The calibration device for a pressure sensor according to claim 6, characterized in that, The signal conversion device is an AD converter.

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