Temperature drift wheatstone bridge model establishing method and device and computer equipment

Abstract

The application discloses a temperature drift Wheatstone bridge model establishing method and device and computer equipment, and relates to the field of circuits. The method comprises the following steps: acquiring voltage data actually output by a Wheatstone bridge under different temperatures to obtain a measured voltage-temperature curve; calculating model parameters of a Wheatstone bridge model according to the voltage-temperature curve, wherein the model parameters comprise a sensitivity drift parameter and a zero-point drift parameter; and establishing a model expression based on the sensitivity drift parameter and the zero-point drift parameter to obtain the Wheatstone bridge model. The Wheatstone bridge model constructed by the method can not only accurately measure resistance, but also can maintain the measurement accuracy and reliability under different temperature conditions.

Description

Technical Field

[0001] This invention relates to the field of circuit technology, and in particular to a method, apparatus, and computer equipment for establishing a temperature-drift Wheatstone bridge model. Background Technology

[0002] A Wheatstone bridge is a circuit used to measure the resistance change of resistive elements. It has two parallel resistive branches that act as voltage dividers for the excitation voltage. The nominal output of each resistive voltage divider is half the excitation voltage. In the ideal condition without a load, the resistance change of the elements is zero, each voltage divider is at the same potential, and the output voltage of the differential bridge is zero. When a load is applied, one or more elements change their resistance, causing a change in the output voltage of the differential bridge. This change can be accurately calculated by differentially measuring the differential bridge. Wheatstone bridges are commonly used in MEMS (Micro-Electro-Mechanical Systems) sensor devices. Based on the piezoresistive effect, they provide feedback signals on the device's state output, further enabling closed-loop control. The piezoresistive effect refers to the phenomenon that the resistance of certain materials changes when subjected to force. This effect can be used to convert mechanical stress into an electrical signal, thereby enabling the detection of physical quantities such as stress and pressure. Piezoresistive sensors are widely used in industry, automotive, and medical fields, and one of their core components is the Wheatstone bridge.

[0003] In modern electronic design automation (EDA), simulation and modeling are crucial for ensuring design reliability and performance. Verilog-A, a hardware description language for simulating circuit behavior, can accurately describe the electrical characteristics of analog circuits, making the design process more flexible, enabling rapid iteration, shortening design cycles, and improving development efficiency. Modeling the Wheatstone bridge using Verilog-A allows for accurate simulation during the circuit design phase, predicting its response under different operating conditions, optimizing design parameters, and, in integrated circuit design, enabling co-simulation with other analog circuit modules to verify the functionality and performance of the entire system.

[0004] The Wheatstone bridge models established in related technologies typically do not consider the effects of temperature on the resistance and sensitivity of components, leading to a decrease in measurement accuracy under varying temperature conditions and an inability to accurately predict actual outputs at different temperatures. Therefore, the applicability of existing models is limited in high-precision measurements and temperature-sensitive applications. Summary of the Invention

[0005] In view of this, this application provides a method and apparatus for establishing a temperature-drift Wheatstone bridge model, the main purpose of which is to solve the technical problem that the measurement results of the existing Wheatstone bridge model are inaccurate due to the influence of temperature.

[0006] According to a first aspect of the present invention, a method for establishing a temperature-drift Wheatstone bridge model is provided, the method comprising:

[0007] Obtain the actual output voltage data of the Wheatstone bridge at different temperatures to obtain the measured voltage-temperature curve;

[0008] Based on the voltage-temperature curve, the model parameters of the Wheatstone bridge model are calculated, including the sensitivity drift parameter and the zero-point drift parameter.

[0009] Based on the sensitivity drift parameter and the zero-point drift parameter, a model expression is established to obtain the Wheatstone bridge model.

[0010] Further, the calculation of the model parameters of the Wheatstone bridge model based on the voltage-temperature curve includes:

[0011] By fitting the voltage-temperature curve, the relationship between the output voltage and temperature of the Wheatstone bridge can be obtained;

[0012] Based on the relationship between output voltage and temperature and the calculated relationship between piezoresistive sensitivity and output voltage, the relationship between piezoresistive sensitivity and temperature is obtained.

[0013] The sensitivity drift parameter is calculated based on the relationship between piezoresistive sensitivity and temperature.

[0014] Based on the voltage-temperature curve, the process error of each resistor in the Wheatstone bridge is measured, and the zero-point drift parameter is obtained.

[0015] Furthermore, the relationship between the piezoresistive sensitivity and temperature includes:

[0016] S = a0 - a(T - T0);

[0017] Where S is the piezoresistive sensitivity, a0 is the initial voltage value, a is the temperature drift coefficient, T is the current temperature, and T0 is the operating temperature.

[0018] Furthermore, the sensitivity drift parameter is calculated based on the relationship between piezoresistive sensitivity and temperature, including:

[0019] Based on the relationship between piezoresistive sensitivity and temperature, the actual sensitivity corresponding to the current temperature can be calculated.

[0020] The sensitivity drift parameter is calculated based on the actual sensitivity.

[0021] The formulas for calculating the actual sensitivity and the sensitivity drift parameter are as follows:

[0022]

[0023] Wherein, sen_temp is the actual sensitivity, a0 is the initial voltage value, a is the temperature drift coefficient, T is the current temperature, R_sen is the sensitivity drift parameter, and V(sig) is the driving signal.

[0024] Further, the step of establishing a model expression based on the sensitivity drift parameter and the zero-point drift parameter to obtain the Wheatstone bridge model includes:

[0025] Construct the individual arms of the Wheatstone bridge, where each arm contains a resistor;

[0026] Based on the sensitivity drift parameter and the zero-point drift parameter, each resistor is compensated, and a resistance compensation expression is established.

[0027] Based on the resistance compensation expression, the voltage corresponding to each resistor is calculated, the model expression is established, and the Wheatstone bridge model is obtained.

[0028] Furthermore, the step of calculating the voltage corresponding to each resistor based on the resistance compensation expression and establishing a model expression includes:

[0029]

[0030] Wherein, R1 is the first resistor, V1 is the voltage corresponding to the first resistor, I1 is the current corresponding to the first resistor, delta1 is the zero-point drift parameter of the first resistor, R2 is the second resistor, V2 is the voltage corresponding to the second resistor, I2 is the current corresponding to the second resistor, delta2 is the zero-point drift parameter of the second resistor, R3 is the third resistor, V3 is the voltage corresponding to the third resistor, I3 is the current corresponding to the third resistor, delta3 is the zero-point drift parameter of the third resistor, R4 is the fourth resistor, V4 is the voltage corresponding to the fourth resistor, I4 is the current corresponding to the fourth resistor, delta4 is the zero-point drift parameter of the fourth resistor, and R_sen is the sensitivity drift parameter.

[0031] Furthermore, after obtaining the Wheatstone bridge model, the method further includes:

[0032] Simulations were performed based on the Wheatstone bridge model to obtain the simulated voltage-temperature curves.

[0033] The temperature drift characteristics of the Wheatstone bridge are verified based on the simulated voltage-temperature curves.

[0034] According to a second aspect of the present invention, a temperature-drift Wheatstone bridge model building apparatus is provided, the apparatus comprising:

[0035] The data processing module is used to acquire the actual output voltage data of the Wheatstone bridge at different temperatures and obtain the measured voltage-temperature curve.

[0036] The parameter calculation module is used to calculate the model parameters of the Wheatstone bridge model based on the voltage-temperature curve, wherein the model parameters include sensitivity drift parameters and zero-point drift parameters;

[0037] The model building module is used to establish a model expression based on the sensitivity drift parameter and the zero-point drift parameter, thereby obtaining the Wheatstone bridge model.

[0038] According to a third aspect of the present invention, a storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the above-described method for establishing a temperature drift Wheatstone bridge model.

[0039] According to a fourth aspect of the present invention, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the above-described method for establishing a temperature-drift Wheatstone bridge model.

[0040] This invention provides a method, apparatus, storage medium, and computer device for establishing a temperature-drift Wheatstone bridge model. First, the actual voltage output data of the Wheatstone bridge at different temperatures is acquired to obtain a measured voltage-temperature curve. Then, based on the voltage-temperature curve, the model parameters of the Wheatstone bridge model are calculated, including sensitivity drift parameters and zero-point drift parameters. Finally, based on the sensitivity drift parameters and the zero-point drift parameters, a model expression is established to obtain the Wheatstone bridge model. This application considers the zero-point drift and sensitivity drift characteristics of the Wheatstone bridge and uses Verilog A to construct the Wheatstone bridge model. The Wheatstone bridge model constructed in this way can not only accurately measure resistance but also maintain measurement accuracy and reliability under different temperature conditions.

[0041] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0042] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0043] Figure 1A circuit diagram of a basic Wheatstone bridge provided by an embodiment of the present invention is shown;

[0044] Figure 2 A flowchart illustrating a method for establishing a temperature-drift Wheatstone bridge model according to an embodiment of the present invention is shown.

[0045] Figure 3 This diagram illustrates a measured voltage-temperature curve of a Wheatstone bridge according to an embodiment of the present invention.

[0046] Figure 4 This diagram illustrates the voltage-temperature curve of a simulated Wheatstone bridge model provided in an embodiment of the present invention.

[0047] Figure 5 This diagram illustrates the structure of a temperature drift Wheatstone bridge model building device provided in an embodiment of the present invention.

[0048] Figure 6 The diagram shows a schematic of the structure of a computer device for implementing a method for establishing a temperature-drift Wheatstone bridge model, according to an embodiment of the present invention. Detailed Implementation

[0049] The present invention will be described in detail below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. In the various embodiments shown below, the terms "first," "second," and various numerical designations are merely for descriptive convenience and are not intended to limit the scope of the embodiments of this application.

[0050] The Wheatstone bridge is commonly used in MEMS (Micro-Electro-Mechanical System) sensor devices. Based on the piezoresistive effect, it provides feedback signals to the device's state, further enabling closed-loop control. The piezoresistive effect refers to the phenomenon where the resistance of certain materials changes when subjected to force. This effect can be used to convert mechanical stress into an electrical signal, thereby enabling the detection of physical quantities such as stress and pressure. Piezoresistive sensors are widely used in industrial, automotive, and medical fields, and one of their core components is the Wheatstone bridge.

[0051] A Wheatstone bridge is a circuit used to measure the resistance change of resistive elements. It has two sets of parallel resistor branches that act as the excitation voltage V. EXCITATION A voltage divider. The nominal output of each resistor divider is the excitation voltage V. EXCITATION Half of the resistance, without any applied load, results in zero change in resistance ΔR for the component. Assume an ideal system, such as... Figure 1As shown, a basic configuration circuit of a Wheatstone bridge is provided, wherein the nominal resistance of each component is R, each voltage divider is at the same potential, and the output voltage of the differential bridge is V. out The resistance is zero. When a load is applied, one or more components will change their resistance, making ΔR≠0Ω, which causes the output voltage of the differential bridge to change. This change can be accurately calculated by performing differential measurements on the differential bridge.

[0052] In modern electronic design automation (EDA), simulation and modeling are crucial for ensuring design reliability and performance. Verilog-A, a hardware description language for simulating circuit behavior, can accurately describe the electrical characteristics of analog circuits, making the design process more flexible, enabling rapid iteration, shortening design cycles, and improving development efficiency. Modeling the Wheatstone bridge using Verilog-A allows for accurate simulation during the circuit design phase, predicting its response under different operating conditions, optimizing design parameters, and, in integrated circuit design, enabling co-simulation with other analog circuit modules to verify the functionality and performance of the entire system.

[0053] The Wheatstone bridge models established in related technologies typically do not consider the effects of temperature on the resistance and sensitivity of components, leading to a decrease in measurement accuracy under varying temperature conditions and an inability to accurately predict actual outputs at different temperatures. Therefore, the applicability of existing models is limited in high-precision measurements and temperature-sensitive applications.

[0054] Based on the above problems, this application provides a method for establishing a temperature-drift Wheatstone bridge model. In one embodiment, as follows: Figure 2 As shown, the method includes the following steps:

[0055] 101. Obtain the actual output voltage data of the Wheatstone bridge at different temperatures to obtain the measured voltage-temperature curve.

[0056] 102. Based on the voltage-temperature curve, the model parameters of the Wheatstone bridge model are calculated, including the sensitivity drift parameter and the zero-point drift parameter.

[0057] 103. Based on the sensitivity drift parameter and the zero drift parameter, establish the model expression to obtain the Wheatstone bridge model.

[0058] In this embodiment, a Wheatstone bridge in a MEMS can be measured to obtain a voltage-temperature curve. Specifically, a preset temperature range can be established, such as -20 degrees Celsius to 80 degrees Celsius. Output voltage data of the Wheatstone bridge at different temperatures within this preset range can be collected, and a voltage-temperature curve can be plotted based on the corresponding output voltage data at different temperatures. In one example, the voltage-temperature curve can be as follows: Figure 3 As shown.

[0059] After obtaining the voltage-temperature curve, it is fitted to derive the voltage-temperature relationship. Based on the calculated relationship between the output voltage and piezoresistive sensitivity of the Wheatstone bridge, the relationship between piezoresistive sensitivity and temperature is obtained. Then, based on this relationship, the sensitivity drift parameter is calculated. Furthermore, based on the voltage-temperature curve, the zero-point drift parameter of each resistor in the Wheatstone bridge due to process errors is obtained. Based on the zero-point drift parameter and the sensitivity drift parameter, the model parameters of the Wheatstone bridge model are obtained.

[0060] In this embodiment, considering the zero-point drift and sensitivity drift characteristics of the Wheatstone bridge, temperature drift of the Wheatstone bridge is compensated using zero-point drift parameters and sensitivity drift parameters. Zero-point drift refers to the zero-point output caused by the resistance values ​​on the four arms of the Wheatstone bridge not being completely equal due to manufacturing processes, etc. Sensitivity drift refers to the change in resistance under pressure caused by the change in the piezoresistive coefficient with temperature. Therefore, when establishing the Wheatstone bridge model, sensitivity drift parameters and zero-point drift parameters are introduced into the model expression to construct a temperature-drift Wheatstone bridge model.

[0061] This invention provides a method, apparatus, storage medium, and computer device for establishing a temperature-drift Wheatstone bridge model. First, the actual voltage output data of the Wheatstone bridge at different temperatures is acquired to obtain a measured voltage-temperature curve. Then, based on the voltage-temperature curve, the model parameters of the Wheatstone bridge model are calculated, including sensitivity drift parameters and zero-point drift parameters. Finally, based on the sensitivity drift parameters and the zero-point drift parameters, a model expression is established to obtain the Wheatstone bridge model. This application considers the zero-point drift and sensitivity drift characteristics of the Wheatstone bridge and uses Verilog A language to construct the Wheatstone bridge model. The Wheatstone bridge model constructed in this way can not only accurately measure resistance but also maintain measurement accuracy and reliability under different temperature conditions.

[0062] Furthermore, to fully illustrate the implementation process of this embodiment, the specific implementation methods of the above embodiments are refined and expanded below. Specifically, in the above embodiments, taking... Figure 1Taking the Wheatstone bridge shown as an example, the output voltage of the Wheatstone bridge is calculated from the voltage difference between the resistors on both sides, as shown in the following expression:

[0063]

[0064] In formula (1), V out V is the output voltage of the Wheatstone bridge. EXCIATION R is the excitation voltage, R is the resistance of each resistive element, and ΔR is the change in resistance.

[0065] An electrical model of a Wheatstone bridge can be established based on formula (1). In the use of Wheatstone bridges, a constant current source is often used to power the bridge. The expression for the output voltage of the Wheatstone bridge can be transformed into formula (2):

[0066] V out =I in ΔR; (2)

[0067] In formula (2), I in The current is the constant current source.

[0068] In reality, the resistive elements in a Wheatstone bridge are typically made of semiconductor materials, exhibiting temperature sensitivity. The ambient temperature affects the resistance value, leading to errors in the output of sensors that use the Wheatstone bridge as a core component. For embedded piezoresistors, temperature drift includes zero-point temperature drift and sensitivity temperature drift. Zero-point temperature drift is primarily caused by the manufacturing process, resulting in slightly different resistance values ​​for each resistor. Sensitivity drift includes the change in bridge arm resistance due to temperature variations, denoted as ΔR. t The change in resistance under pressure due to temperature-induced changes in the piezoresistive coefficient, and consequently the change in resistance, is denoted as ΔR. r Based on this, the formula for calculating the output voltage of a temperature-drifted Wheatstone bridge can be expressed as:

[0069]

[0070] In formula (3), V out V is the output voltage of the Wheatstone bridge. ref R is the supply voltage, R is the nominal resistance of the Wheatstone bridge, and ΔR is the change in resistance caused by the load (pressure). ΔR in the numerator of formula (3) t It is canceled out, and ΔR t It is usually much smaller than R, so ΔR t This can be ignored. Therefore, the expression for the output voltage of the Wheatstone bridge is approximately:

[0071]

[0072] Therefore, in the embodiments of this application, the sensitivity temperature drift is mainly caused by the change of the piezoresistive coefficient with temperature. In one example, if in an N-type silicon semiconductor... <100> Diffusion doping on surface-oriented thin films <110> For a P-type resistor with a specific crystal orientation, the piezoresistive coefficient is approximately:

[0073] π l =-π t =π 44 / 2;(5)

[0074] Where, π l π is the longitudinal piezoresistive coefficient. t π is the transverse piezoresistive coefficient. 44 Let be the piezoresistive coefficient along the crystal axis. According to formula (5), the change in piezoresistive resistance is:

[0075]

[0076] In formula (6), σ x The transverse stress of the resistor is proportional to the pressure of the silicon thin film, σ. y The stress in the longitudinal direction of the resistor is proportional to the pressure of the silicon thin film.

[0077] Based on formulas (4) and (6), the calculation formulas for the output voltage and piezoresistive sensitivity of the Wheatstone bridge are as follows:

[0078]

[0079] Where S is the piezoresistive sensitivity. Furthermore, the piezoresistive sensitivity can be expressed as:

[0080]

[0081] According to formula (9), it can be seen that the piezoresistive sensitivity is inversely proportional to the temperature.

[0082] In one embodiment, in step 102, the model parameters of the Wheatstone bridge model are calculated based on the voltage-temperature curve. Specifically, this can be achieved by: fitting the voltage-temperature curve to obtain the relationship between the output voltage and temperature of the Wheatstone bridge; obtaining the relationship between the piezoresistive sensitivity and temperature based on the relationship between the output voltage and temperature and the calculated relationship between the piezoresistive sensitivity and the output voltage; calculating the sensitivity drift parameter based on the relationship between the piezoresistive sensitivity and temperature; and measuring the process error of each resistor in the Wheatstone bridge based on the voltage-temperature curve to obtain the zero-point drift parameter.

[0083] In the above embodiments, the measured voltage-temperature curve of the Wheatstone bridge is as follows: Figure 3As shown, by fitting the voltage-temperature curve, the specific relationship between the Wheatstone bridge and temperature is as follows:

[0084] V out =V0-k(T-T0); (10)

[0085] In formula (10), V out V0 represents the output voltage of the Wheatstone bridge, V0 is the corresponding voltage value, k is a coefficient, T is the current temperature, and T0 is the operating temperature. The coefficient k can be determined by the output voltage V0. out The derivative with respect to temperature T is obtained.

[0086] Then, based on formula (10) and the calculated relationship between the output voltage of the Wheatstone bridge and the piezoresistive sensitivity, the relationship between piezoresistive sensitivity and temperature can be obtained:

[0087] S = a0 - a(T - T0); (11)

[0088] Where S is the piezoresistive sensitivity, a0 is the initial voltage value, a is the temperature drift coefficient, T is the current temperature, and T0 is the operating temperature.

[0089] The sensitivity drift parameter can be calculated using formula (11).

[0090] In one embodiment, the sensitivity drift parameter is calculated based on the relationship between piezoresistive sensitivity and temperature. Specifically, this can be achieved by: calculating the actual sensitivity corresponding to the current temperature based on the relationship between piezoresistive sensitivity and temperature; and calculating the sensitivity drift parameter based on the actual sensitivity. The calculation formulas for the actual sensitivity and the sensitivity drift parameter are as follows:

[0091] sen_temp = a0 - a*T; (12)

[0092] R_sen=V(sig)*sen_temp; (13)

[0093] Wherein, sen_temp is the actual sensitivity, a0 is the initial voltage value, a is the temperature drift coefficient, T is the current temperature, R_sen is the sensitivity drift parameter, and V(sig) is the driving signal.

[0094] After obtaining the zero-point drift parameters and sensitivity drift parameters for each resistor, temperature drift is compensated using these parameters to construct a Wheatstone bridge model. In one embodiment, the specific construction method of the Wheatstone bridge model is as follows: construct each arm of the Wheatstone bridge, wherein each arm contains a resistor; compensate for each resistor based on the sensitivity drift parameters and zero-point drift parameters, and establish a resistance compensation expression; calculate the voltage corresponding to each resistor based on the resistance compensation expression, establish a model expression, and obtain the Wheatstone bridge model.

[0095] Based on the analysis of the temperature drift of the Wheatstone bridge and the formula for its output voltage in the above embodiments, each resistor in the Wheatstone bridge is compensated using temperature drift parameters and sensitivity drift parameters to obtain a resistance compensation expression. A Wheatstone bridge model is then constructed based on this expression. The resistance compensation expression for each resistor in the Wheatstone bridge is as follows:

[0096]

[0097] Wherein, R1 is the first resistor, delta1 is the zero-point drift parameter of the first resistor, R2 is the second resistor, delta2 is the zero-point drift parameter of the second resistor, R3 is the third resistor, delta3 is the zero-point drift parameter of the third resistor, R4 is the fourth resistor, delta4 is the zero-point drift parameter of the fourth resistor, and R_sen is the sensitivity drift parameter.

[0098] Furthermore, in this embodiment of the application, based on the resistance compensation expression, the voltage corresponding to each resistor is calculated, and a model expression is established, including:

[0099]

[0100] Where V1 is the voltage corresponding to the first resistor, I1 is the current corresponding to the first resistor, V2 is the voltage corresponding to the second resistor, I2 is the current corresponding to the second resistor, V3 is the voltage corresponding to the third resistor, I3 is the current corresponding to the third resistor, V4 is the voltage corresponding to the fourth resistor, and I4 is the current corresponding to the fourth resistor.

[0101] In a specific example, based on the above embodiments, the following is a partial code of the temperature-drift Wheatstone bridge model built using Verilog A:

[0102] 1. include "constants.vams" / / Includes a file named "constants.vams", which may define some constants or parameters for use by subsequent code.

[0103] 2. include "disciplines.vams" / / Includes a file named "disciplines.vams", which may define some model or behavioral specifications for use by subsequent code.

[0104] 3. module bridge(VDD, sig, von, vop, GND); / / Defines a module named "bridge" with five ports: VDD, sig, von, vop, and GND. VDD and GND are input ports, sig is an input port, and von and vop are output ports.

[0105] 4. input sig; / / Declare an input port named sig.

[0106] 5. input VDD, GND; / / Declares two input ports, VDD and GND.

[0107] 6.output von, vop; / / Declares two output ports, von and vop.

[0108] 7. electrical sig,VDD,GND,von,vop; / / Declares the electrical variables sig,VDD,GND,von, andvop, where von is the negative terminal of the Wheatstone bridge output and vop is the positive terminal of the output.

[0109] 8. branch(VDD, von) res1; / / Declare a branch (bridge arm) named res1 that connects VDD and von.

[0110] 9. parameter real R1 = X; / / Defines a real parameter named R1 (first resistor), with a default value of X.

[0111] 10. branch(VDD, vop) res2; / / Declare a branch (bridge arm) named res2 that connects VDD and vop.

[0112] 11. parameter real R2 = X; / / Defines a real parameter named R2 (second resistor), with a default value of X.

[0113] 12.branch(von,GND)res3; / / Declare a branch (bridge arm) named res3, which connects von and GND.

[0114] 13. parameter real R3 = X; / / Defines a real parameter named R3 (third resistor), with a default value of X.

[0115] 14. branch(vop, GND) res4; / / Declare a branch (bridge arm) named res4, which connects vop and GND.

[0116] 15. parameter real R4 = X; / / Defines a real parameter named R4 (fourth resistor), with a default value of X.

[0117] 16. parameter real sen = A; / / Defines a real number parameter named sen, with a default value of A, which is a in the above example.

[0118] 17. parameter real delta1 = B; / / Defines a real number parameter named delta1, with a default value of B.

[0119] 18. parameter real delta2 = B; / / Defines a real number parameter named delta2, with a default value of B.

[0120] 19. parameter real delta3 = B; / / Defines a real number parameter named delta3, with a default value of B.

[0121] 20. parameter real delta4 = B; / / Defines a real number parameter named delta4, with a default value of B.

[0122] 22.real sen_temp; / / Declare a real variable named sen_temp.

[0123] 23.real temp; / / Declare a real variable named temp.

[0124] 24.real R_sen; / / Declare a real variable named R_sen.

[0125] 25. analog begin / / Enter the simulation statement block, used to describe the simulation behavior.

[0126] 26. temp = Stemperature; / / Get the current temperature, i.e., the temperature T in the above embodiment, and assign it to the temp variable.

[0127] 27. sen_temp = C - sen * temp; / / Calculate the value of the variable sen_temp based on temperature. sen_temp represents the actual sensitivity after temperature change, used to reflect sensitivity drift. C is a parameter constant, which is the initial value of the voltage output, i.e., a0 in the above embodiment.

[0128] 28. R_sen = V(sig) * sen_temp; / / Calculate the value of the variable R_sen. This represents the value obtained under the influence of the sig signal.

[0129] 29.V(res1)<+I(res1)*(R1*(1+delta1)-R_sen);

[0130] V(res2)<+I(res2)*(R2*(1+delta2)+R_sen);

[0131] V(res3)<+I(res3)*(R3*(1+delta3)+R_sen);

[0132] V(res4)<+I(res4)*(R4*(1+delta4)-R_sen); / / Assign a value for each branch (bridge arm). (1+delta1) to (1+delta4) represent the error of resistors R1 to R4 respectively. This error is caused by zero-point drift due to process and temperature.

[0133] 30.end` / / End the simulated statement block.

[0134] 31. `Endmodule` / / End the module definition.

[0135] In one embodiment, after establishing a temperature-drift Wheatstone bridge model, simulation is performed based on the Wheatstone bridge model to obtain the simulated voltage-temperature curve; based on the simulated voltage-temperature curve, the temperature drift characteristics of the Wheatstone bridge are verified. Specifically, a voltage value of 1V can be applied to the sig signal, representing a constant pressure on the Wheatstone bridge to stabilize the output. Due to temperature changes, the voltage output of the Wheatstone bridge will change. In one example, the simulation results are as follows... Figure 4 As shown in the simulation results, the voltage-temperature curves indicate that the output voltage of the Wheatstone bridge model constructed in this embodiment satisfies the temperature drift characteristic.

[0136] The temperature drift Wheatstone bridge model establishment method provided in this application starts from a more accurate physical output mechanism and temperature drift mechanism. Based on the original Wheatstone bridge model, it adds zero-point drift parameters and sensitivity drift parameters to compensate for temperature drift. The resulting temperature drift Wheatstone bridge model has more accurate output results in circuit simulation, which is beneficial for more accurate MEMS sensor feedback circuit design.

[0137] Furthermore, as Figure 2 The specific implementation of the method shown in this embodiment provides a device for establishing a temperature-drift Wheatstone bridge model, such as... Figure 5 As shown, the device includes: a data processing module 31, a parameter calculation module 32, and a model building module 33.

[0138] Data processing module 31 can be used to acquire the actual output voltage data of Wheatstone bridge at different temperatures and obtain the measured voltage-temperature curve;

[0139] The parameter calculation module 32 can be used to calculate the model parameters of the Wheatstone bridge model based on the voltage-temperature curve, wherein the model parameters include sensitivity drift parameters and zero-point drift parameters;

[0140] The model building module 33 can be used to establish a model expression based on the sensitivity drift parameter and the zero drift parameter to obtain the Wheatstone bridge model.

[0141] In specific application scenarios, the model parameters of the Wheatstone bridge model are calculated based on the voltage-temperature curve. Specifically, the parameter calculation module 32 can be used to fit the voltage-temperature curve to obtain the relationship between the output voltage and temperature of the Wheatstone bridge; based on the relationship between the output voltage and temperature and the calculated relationship between the piezoresistive sensitivity and the output voltage, the relationship between the piezoresistive sensitivity and temperature is obtained; based on the relationship between the piezoresistive sensitivity and temperature, the sensitivity drift parameter is calculated; and based on the voltage-temperature curve, the process error of each resistor in the Wheatstone bridge is measured to obtain the zero-point drift parameter. The relationship between the piezoresistive sensitivity and temperature includes: S = a0 - a(T - T0); where S is the piezoresistive sensitivity, a0 is the initial voltage value, a is the temperature drift coefficient, T is the current temperature, and T0 is the operating temperature.

[0142] In specific application scenarios, the sensitivity drift parameter is calculated based on the relationship between piezoresistive sensitivity and temperature. Specifically, the parameter calculation module 32 can be used to calculate the actual sensitivity corresponding to the current temperature based on the relationship between piezoresistive sensitivity and temperature; and to calculate the sensitivity drift parameter based on the actual sensitivity. The calculation formulas for the actual sensitivity and the sensitivity drift parameter are as follows:

[0143]

[0144] Wherein, sen_temp is the actual sensitivity, a0 is the initial voltage value, a is the temperature drift coefficient, T is the current temperature, R_sen is the sensitivity drift parameter, and V(sig) is the driving signal.

[0145] In a specific application scenario, based on the sensitivity drift parameter and the zero-point drift parameter, a model expression is established to obtain the Wheatstone bridge model. The model establishment module 33 can be used to construct each arm of the Wheatstone bridge, wherein each arm contains a resistor; based on the sensitivity drift parameter and the zero-point drift parameter, each resistor is compensated to establish a resistor compensation expression; based on the resistor compensation expression, the voltage corresponding to each resistor is calculated to establish a model expression, thus obtaining the Wheatstone bridge model.

[0146] In specific application scenarios, the model building module 33 calculates the voltage corresponding to each resistor based on the resistance compensation expression and establishes the model expression, including:

[0147]

[0148] Wherein, R1 is the first resistor, V1 is the voltage corresponding to the first resistor, I1 is the current corresponding to the first resistor, delta1 is the zero-point drift parameter of the first resistor, R2 is the second resistor, V2 is the voltage corresponding to the second resistor, I2 is the current corresponding to the second resistor, delta2 is the zero-point drift parameter of the second resistor, R3 is the third resistor, V3 is the voltage corresponding to the third resistor, I3 is the current corresponding to the third resistor, delta3 is the zero-point drift parameter of the third resistor, R4 is the fourth resistor, V4 is the voltage corresponding to the fourth resistor, I4 is the current corresponding to the fourth resistor, delta4 is the zero-point drift parameter of the fourth resistor, and R_sen is the sensitivity drift parameter.

[0149] In specific application scenarios, this device also includes a simulation verification module 34. The simulation verification module 34 can be used to perform simulation based on the Wheatstone bridge model after obtaining the Wheatstone bridge model, and obtain the simulated voltage-temperature curve; based on the simulated voltage-temperature curve, the temperature drift characteristics of the Wheatstone bridge are verified.

[0150] It should be noted that other corresponding descriptions of the functional units involved in the temperature drift Wheatstone bridge model building device provided in this embodiment can be found in [reference]. Figure 2 The corresponding descriptions in [the document] will not be repeated here. Based on the above... Figure 2 Accordingly, this embodiment also provides a storage medium storing a computer program that, when executed by a processor, implements the above-described method. Figure 2 The method for establishing the temperature drift Wheatstone bridge model is shown.

[0151] Based on this understanding, the technical solution of this application can be embodied in the form of a software product. The software product to be identified can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, or portable hard drive), including several instructions to cause a computer device (such as a personal computer, server, or network device) to execute the methods described in the various implementation scenarios of this application.

[0152] Based on the above, Figure 2 The method shown, and Figure 5 The illustrated embodiment of the temperature drift Wheatstone bridge model building device is designed to achieve the above objectives, such as... Figure 6 As shown, this embodiment also provides a computer device for establishing a temperature-drift Wheatstone bridge model, which can be a personal computer, server, smartphone, tablet computer, smartwatch, or other network device, etc. The computer device includes a storage medium and a processor; the storage medium is used to store computer programs and an operating system; the processor is used to execute the computer program to achieve the above-mentioned... Figure 2 The method shown.

[0153] Optionally, the computer device may also include internal memory, a communication interface, a network interface, a camera, radio frequency (RF) circuitry, sensors, audio circuitry, a Wi-Fi module, a display screen, and input devices such as a keyboard. The communication interface may also include a USB interface, a card reader interface, etc. The network interface may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface).

[0154] Those skilled in the art will understand that the computer device structure established by the temperature drift Wheatstone bridge model provided in this embodiment does not constitute a limitation on the computer device, and may include more or fewer components, or combine certain components, or have different component arrangements.

[0155] The storage medium may also include an operating system and a network communication module. The operating system is a program that manages the aforementioned computer hardware and the software resources to be identified, supporting the operation of information processing programs and other software and / or programs to be identified. The network communication module is used to enable communication between the various components within the storage medium, as well as communication with other hardware and software in the information processing computer device.

[0156] Through the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented using software plus necessary general-purpose hardware platforms, or it can be implemented in hardware. By applying the technical solution of this application, firstly, the actual output voltage data of the Wheatstone bridge at different temperatures is obtained to obtain the measured voltage-temperature curve; then, based on the voltage-temperature curve, the model parameters of the Wheatstone bridge model are calculated, wherein the model parameters include sensitivity drift parameters and zero-point drift parameters; finally, based on the sensitivity drift parameters and the zero-point drift parameters, a model expression is established to obtain the Wheatstone bridge model. Compared with the prior art, this application considers the zero-point drift and sensitivity drift characteristics of the Wheatstone bridge and uses Verilog A to construct the Wheatstone bridge model. The Wheatstone bridge model constructed in this way can not only accurately measure resistance, but also maintain measurement accuracy and reliability under different temperature conditions.

[0157] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of a preferred embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing this application. Those skilled in the art will understand that the modules in the apparatus of the embodiment can be distributed within the apparatus of the embodiment as described, or can be modified to be located in one or more apparatuses different from this embodiment. The modules of the above-described embodiment can be combined into one module, or further divided into multiple sub-modules.

[0158] The serial numbers in this application are for descriptive purposes only and do not represent the superiority or inferiority of any particular implementation scenario. The above disclosures are merely a few specific implementation scenarios of this application; however, this application is not limited thereto, and any variations conceived by those skilled in the art should fall within the protection scope of this application.

Claims

1. A method for establishing a temperature-drift Wheatstone bridge model, characterized in that, The method includes: Obtain the actual output voltage data of the Wheatstone bridge at different temperatures to obtain the measured voltage-temperature curve; Based on the voltage-temperature curve, the model parameters of the Wheatstone bridge model are calculated, including the sensitivity drift parameter and the zero-point drift parameter. Based on the sensitivity drift parameters and the zero-point drift parameters, a model expression is established to obtain the Wheatstone bridge model, including: constructing each arm of the Wheatstone bridge, wherein each arm contains a resistor; compensating for each resistor based on the sensitivity drift parameters and the zero-point drift parameters, and establishing a resistor compensation expression; calculating the voltage corresponding to each resistor based on the resistor compensation expression, establishing a model expression, and obtaining the Wheatstone bridge model. The process involves calculating the voltage corresponding to each resistor based on the resistance compensation expression and establishing a model expression, including: ； in, The first resistor, This is the voltage corresponding to the first resistor. This represents the current corresponding to the first resistor. The zero-point drift parameter of the first resistor. For the second resistor, This is the voltage corresponding to the second resistor. This is the current corresponding to the second resistor. The zero-point drift parameter of the second resistor. The third resistor, This is the voltage corresponding to the third resistor. This is the current corresponding to the third resistor. The zero-point drift parameter of the third resistor. The fourth resistor, This is the voltage corresponding to the fourth resistor. This is the current corresponding to the fourth resistor. The zero-point drift parameter of the fourth resistor. The sensitivity drift parameter is denoted as .

2. The method according to claim 1, characterized in that, The calculation of model parameters for the Wheatstone bridge model based on the voltage-temperature curve includes: By fitting the voltage-temperature curve, the relationship between the output voltage and temperature of the Wheatstone bridge can be obtained; Based on the relationship between output voltage and temperature and the calculated relationship between piezoresistive sensitivity and output voltage, the relationship between piezoresistive sensitivity and temperature is obtained. The sensitivity drift parameter is calculated based on the relationship between piezoresistive sensitivity and temperature. Based on the voltage-temperature curve, the process error of each resistor in the Wheatstone bridge is measured, and the zero-point drift parameter is obtained.

3. The method according to claim 2, characterized in that, The relationship between the piezoresistive sensitivity and temperature includes: ； in, For piezoresistive sensitivity, This is the initial voltage value. This is the temperature drift coefficient. The current temperature. This refers to the operating temperature.

4. The method according to claim 3, characterized in that, The sensitivity drift parameters are calculated based on the relationship between piezoresistive sensitivity and temperature, including: Based on the relationship between piezoresistive sensitivity and temperature, the actual sensitivity corresponding to the current temperature can be calculated. The sensitivity drift parameter is calculated based on the actual sensitivity. The formulas for calculating the actual sensitivity and the sensitivity drift parameter are as follows: ； in, The actual sensitivity is... This is the initial voltage value. This is the temperature drift coefficient. The current temperature. The sensitivity drift parameter is... This is the driving signal.

5. The method according to claim 1, characterized in that, After obtaining the Wheatstone bridge model, the method further includes: Simulations were performed based on the Wheatstone bridge model to obtain the simulated voltage-temperature curves. The temperature drift characteristics of the Wheatstone bridge are verified based on the simulated voltage-temperature curves.

6. A device for establishing a temperature-drift Wheatstone bridge model, characterized in that, The device includes: The data processing module is used to acquire the actual output voltage data of the Wheatstone bridge at different temperatures and obtain the measured voltage-temperature curve. The parameter calculation module is used to calculate the model parameters of the Wheatstone bridge model based on the voltage-temperature curve, wherein the model parameters include sensitivity drift parameters and zero-point drift parameters; The model building module is used to establish a model expression based on the sensitivity drift parameter and the zero-point drift parameter to obtain the Wheatstone bridge model; The model building module is specifically used to build each arm of the Wheatstone bridge, wherein each arm contains a resistor; based on the sensitivity drift parameter and the zero-point drift parameter, each resistor is compensated and a resistance compensation expression is established; based on the resistance compensation expression, the voltage corresponding to each resistor is calculated and a model expression is established to obtain the Wheatstone bridge model. The step of calculating the voltage corresponding to each resistor and establishing a model expression based on the resistance compensation expression includes: ； in, The first resistor, This is the voltage corresponding to the first resistor. This represents the current corresponding to the first resistor. The zero-point drift parameter of the first resistor. For the second resistor, This is the voltage corresponding to the second resistor. This is the current corresponding to the second resistor. The zero-point drift parameter of the second resistor. The third resistor, This is the voltage corresponding to the third resistor. This is the current corresponding to the third resistor. The zero-point drift parameter of the third resistor. The fourth resistor, This is the voltage corresponding to the fourth resistor. This is the current corresponding to the fourth resistor. The zero-point drift parameter of the fourth resistor. The sensitivity drift parameter is denoted as .

7. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 5.

8. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 5.

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