A method, compensation circuit and mainboard for compensating the measurement accuracy of a silicon voltage sensor.

Abstract

This invention relates to the field of silicon pressure sensor detection technology, and more specifically, to a method, compensation circuit, and mainboard for compensating the measurement accuracy of silicon pressure sensors. This invention proposes a method for linear calibration, which can correct nonlinear errors as needed. This invention integrates a temperature detection module into the target silicon pressure sensor, enabling temperature detection of the target silicon pressure sensor, and provides a temperature compensation method that can promptly correct the temperature drift error of the target silicon pressure sensor. Furthermore, the resources consumed by the linear calibration and temperature compensation calculations of this invention are far less than those of traditional lookup table methods or other conventional methods. This invention solves the problem of two types of errors existing in current silicon pressure sensors.

Description

Technical Field

[0001] This invention relates to the field of silicon voltage sensor detection technology, and in particular to: 1. a method for compensating the measurement accuracy of a silicon voltage sensor; 2. a circuit for compensating the measurement accuracy of a silicon voltage sensor; 3. a mainboard for compensating the measurement accuracy of a silicon voltage sensor. Background Technology

[0002] Silicon pressure sensors are a type of pressure sensor that are now widely used in various fields.

[0003] However, the inventors discovered two shortcomings in its use for high-precision measurement:

[0004] 1. There is a significant temperature drift error, which can reach up to 2% within the ambient temperature range. For example... Figure 1 As shown, this is because the actual zero value, full scale value and standard pressure value of the silicon pressure sensor are not the same at different temperatures (temperature 1, temperature 2), which will cause an error in the pressure linear curve - up to 2%.

[0005] 2. Nonlinear errors exist, typically reaching 0.5%. For example... Figure 2 As shown, at a certain temperature, there is an error between the pressure linear curve and the measured pressure value—up to 0.5%.

[0006] To minimize the impact of the two factors mentioned above, the inventors designed a data processing method and then linearized the measurement data based on microcontroller technology, which can improve the accuracy of the silicon voltage sensor from 2% to 0.04%, thus meeting the requirements for high-precision measurement. Summary of the Invention

[0007] Therefore, it is necessary to provide a measurement accuracy compensation method, compensation circuit and main board for silicon voltage sensors to address the two types of errors present in existing silicon voltage sensors.

[0008] This invention is achieved using the following technical solution:

[0009] In a first aspect, the present invention discloses a method for compensating the measurement accuracy of a silicon pressure sensor, used to compensate the measurement accuracy of a target silicon pressure sensor; the target silicon pressure sensor integrates a temperature detection module.

[0010] The methods for measurement accuracy compensation include:

[0011] S1, perform linear calibration on the target silicon voltage sensor;

[0012] S1 includes:

[0013] S1.1, Obtain the temperature T0 of the target silicon pressure sensor during actual use;

[0014] Keeping T0 constant, N standard pressure values ​​are applied to the target silicon pressure sensor successively, and the target silicon pressure sensor detects N corresponding measured pressure values; where 5≥N≥2;

[0015] S1.2, construct a calibration function based on the N standard pressure values ​​and N measured pressure values ​​corresponding to T0 to obtain the linearly calibrated pressure measurement value P.

[0016] S2, temperature compensation for the target silicon voltage sensor;

[0017] S2 includes:

[0018] S2 includes:

[0019] S2.1, Place the target silicon voltage sensor successively at M preset temperatures T1 to T2. M Below, and at the m-th preset temperature T m X is applied sequentially to the target silicon voltage sensor. SL X SH The target silicon pressure sensor detects the corresponding value.

[0020] Among them, X SL X represents the zero-point pressure value of the target silicon pressure sensor. SH The target silicon pressure sensor's full-scale pressure value. For the target silicon voltage sensor in X SL T m The measured pressure value under the pressure, For X SH The target silicon voltage sensor in X SL T m Measured pressure value;

[0021] S2.2, Select the two preset temperatures T that are closest to T0 from the M preset temperatures. p T q Among them, T P For the p-th preset temperature, T q T is the qth preset temperature; p ≤T0, T q ≥T0;

[0022] S2.3, according to T p T q Based on the data, a set of compensation functions is constructed to obtain the temperature-compensated pressure measurement value P′.

[0023] The measurement accuracy compensation method of this silicon voltage sensor implements the method or process according to embodiments of this disclosure.

[0024] Secondly, the present invention discloses a measurement accuracy compensation circuit for a silicon pressure sensor, comprising: a target silicon pressure sensor, a temperature detection module, a signal amplification module, an STC microcontroller, and peripheral functional circuits.

[0025] The temperature detection module is integrated into the target silicon pressure sensor and is used to detect the temperature T0 at which the target silicon pressure sensor is actually used. The signal amplification module amplifies the detection signal from the target silicon pressure sensor to obtain the measured pressure value. The STC microcontroller is connected to the temperature detection module and the signal amplification module and is used to compensate the measurement accuracy of the target silicon pressure sensor according to the silicon pressure sensor measurement accuracy compensation method disclosed in the first aspect. The peripheral functional circuits are used to ensure the normal operation of the target silicon pressure sensor, the temperature detection module, the signal amplification module, and the STC microcontroller.

[0026] The measurement accuracy compensation circuit of this silicon voltage sensor implements the method or process according to embodiments of this disclosure.

[0027] Thirdly, the present invention discloses a measurement accuracy compensation motherboard for a silicon voltage sensor. The motherboard has a measurement accuracy compensation circuit for the silicon voltage sensor as described in the second aspect printed on it.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. Based on a large amount of experimental data, the inventors of this invention have found that the nonlinear characteristics of silicon voltage sensors are approximately parabolic. Therefore, this invention proposes a method for linear calibration, which can correct nonlinear errors as needed. Furthermore, the computational resources required are far less than those of traditional table lookup methods or other conventional methods.

[0030] 2. This invention integrates a temperature detection module into the target silicon voltage sensor to achieve temperature detection of the target silicon voltage sensor and provides a temperature compensation method that can promptly correct the temperature drift error of the target silicon voltage sensor; moreover, the computational resources required are far less than those of traditional table lookup methods or other conventional methods.

[0031] 3. The method of the present invention has very low technical requirements for microcontrollers. Accuracy compensation can be completed using a domestically produced general-purpose STC microcontroller with a unit price of only 3 yuan, which can meet the high-precision measurement requirements and significantly reduce product costs. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the temperature drift error mentioned in the background art of this invention;

[0033] Figure 2 This is a schematic diagram of the nonlinear error mentioned in the background technology of this invention;

[0034] Figure 3This is a flowchart of the measurement accuracy compensation method for the silicon voltage sensor in Embodiment 1 of the present invention;

[0035] Figure 4 This is a schematic diagram illustrating the principle of two-point calibration in Embodiment 1 of the present invention;

[0036] Figure 5 This is a schematic diagram illustrating the principle of five-point calibration in Embodiment 1 of the present invention;

[0037] Figure 6 This is a comparison of the linear pressure curves at two different temperatures after temperature compensation in Embodiment 1 of the present invention.

[0038] Figure 7 This is a structural diagram of the measurement accuracy compensation circuit of the silicon voltage sensor in Embodiment 2 of the present invention;

[0039] Figure 8 for Figure 6 Enlarged view of the STC microcontroller;

[0040] Figure 9 for Figure 6 Enlarged view of the target silicon pressure sensor and temperature detection module;

[0041] Figure 10 for Figure 6 Enlarged view of the power supply voltage regulator module;

[0042] Figure 11 for Figure 6 Enlarged view of the medium-to-high precision reference module;

[0043] Figure 12 for Figure 6 Enlarged view of the signal amplification module;

[0044] Figure 13 for Figure 6 Enlarged view of the data display module and button operation module;

[0045] Figure 14 for Figure 6 Enlarged view of the RS485 communication module. Detailed Implementation

[0046] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] It should be noted that when a component is said to be "installed on" another component, it can be directly on the other component or it may be in a component that is centered on it. When a component is said to be "set on" another component, it can be directly set on the other component or it may also be in a component that is centered on it. When a component is said to be "fixed to" another component, it can be directly fixed to the other component or it may also be in a component that is centered on it.

[0048] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0049] Example 1

[0050] See Figure 3 , Figure 3 This is a flowchart of the measurement accuracy compensation method for the silicon voltage sensor in Embodiment 1. The measurement accuracy compensation method provided in Embodiment 1 is used to compensate the measurement accuracy of the target silicon voltage sensor. It should be noted that the target silicon voltage sensor integrates a temperature detection module.

[0051] For details, please refer to Figure 3 Methods for compensating for measurement accuracy include:

[0052] S1, perform linear calibration on the target silicon voltage sensor;

[0053] S1 includes:

[0054] S1.1, Obtain the temperature T0 of the target silicon pressure sensor during actual use;

[0055] Keeping T0 constant, N standard pressure values ​​are applied to the target silicon pressure sensor successively, and the target silicon pressure sensor detects N corresponding measured pressure values; where 5≥N≥3;

[0056] S1.2, construct a calibration function based on N standard pressure values ​​and N measured pressure values ​​to obtain the linearly calibrated pressure measurement value P.

[0057] The calibration function constructed varies depending on the value of N:

[0058] First, it should be noted that if N=2, see [link / reference]. Figure 4 This can be considered as two-point calibration:

[0059] In this case, the two standard pressure values ​​include: X SL XSH ; where X SL X represents the zero-point pressure value of the target silicon pressure sensor. SH The target silicon pressure sensor's full-scale pressure value; two measured pressure values ​​include: P SL P SH Among them, P SL For the target silicon voltage sensor at T0, X SL The measured pressure value under the following conditions, P SH For the target silicon voltage sensor at T0, X SH Measured pressure value;

[0060] The calibration function is then P = K * D; where K represents the proportionality coefficient, K = (P SH -P SL ) / P SH D represents the measured pressure value of the target silicon pressure sensor.

[0061] The calibration function has an error of 0.5% compared to the measured pressure curve. In other words, when N is 2, the nonlinear error is not eliminated.

[0062] Therefore, take N≥3:

[0063] 1. When N=3, the three standard pressure values ​​include: X SL X SH X S1 ; where X SL X represents the zero-point pressure value of the target silicon pressure sensor. SH X represents the full-scale pressure value of the target silicon pressure sensor. S1 The pressure value is within the range of the target silicon pressure sensor; X SL <X S1 <X SH ;

[0064] The three measured pressure values ​​include: P SL P SH P1; where P SL For the target silicon voltage sensor at T0, X SL The measured pressure value under the following conditions, P SH For the target silicon voltage sensor at T0, X SH The measured pressure value under the following conditions, P1 is the target silicon pressure sensor at T0, X S1 Measured pressure value under; P SL <P S1 <P SH ;

[0065] Then: when D≤P1, the calibration function is P=K×D×[1+(X S1 -P1) / P1];

[0066] When D≥P1, the calibration function is P=K×D+(X SH -K×D)×(X S1 -P1) / (X SH -P1);

[0067] In the formula, K represents the proportionality coefficient, K = (P SH -P SL ) / P SH D represents the measured pressure value of the target silicon pressure sensor.

[0068] In other words, when N=3, it can be considered that 3-point calibration has been performed.

[0069] 2. When N=4, the four standard pressure values ​​include: X SL X SH X S1 X S2 ; where X SL X represents the zero-point pressure value of the target silicon pressure sensor. SH X represents the full-scale pressure value of the target silicon pressure sensor. S1 X S2 All are pressure values ​​within the range of the target silicon pressure sensor; X SL <X S1 <X S2 <X SH ;

[0070] The four measured pressure values ​​include: P SL P SH P1, P2; where P SL For the target silicon voltage sensor at T0, X SL The measured pressure value under the following conditions, P SH For the target silicon voltage sensor at T0, X SH The measured pressure value under the following conditions, P1 is the target silicon pressure sensor at T0, X S1 The measured pressure value under the following conditions, P2 is the target silicon pressure sensor at T0, X S2 Measured pressure value under; P SL <P1<P2<P SH ;

[0071] Then: when D≤P1, the calibration function is P=K×D×[1+(X S1 -P1) / P1];

[0072] When P1≤D≤P2, the calibration function is:

[0073] P = K × D + X S1 -P1-(K×D-P1)×[(X S1 -P1)-(X S2-P2)] / (P2-P1);

[0074] When D≥P2, the calibration function is: P=K×D+(X SH -K×D)×(X S2 -P2) / (X SH -P2);

[0075] In the formula, K represents the proportionality coefficient, K = (P SH -P SL ) / P SH D represents the measured pressure value of the target silicon pressure sensor.

[0076] In other words, when N=4, it can be considered that 4-point calibration has been performed.

[0077] 3. When N=5, the five standard pressure values ​​include: X SL X SH X S1 X S2 X S3 ; where X SL X represents the zero-point pressure value of the target silicon pressure sensor. SH X represents the full-scale pressure value of the target silicon pressure sensor. S1 X S2 X S3 All are pressure values ​​within the range of the target silicon pressure sensor; X SL <X S1 <X S2 <X S3 <X SH ;

[0078] The five measured pressure values ​​include: P SL P SH P1, P2, P3; where P SL For T0, X SL The measured pressure value of the target silicon pressure sensor, P SH For the target silicon voltage sensor at T0, X SH The measured pressure value under the following conditions, P1 is the target silicon pressure sensor at T0, X S1 The measured pressure value under the following conditions, P2 is the target silicon pressure sensor at T0, X S2 The measured pressure value under the following conditions; P3 is the target silicon pressure sensor at T0, X S3 Measured pressure value under; P SL <P1<P2<P3<P SH ;

[0079] Then: when D≤P1, the calibration function is P=K×D×[1+(X S1 -P1) / P1];

[0080] When P1≤D≤P2, the calibration function is:

[0081] P = K × D + X S1 -P1-(K×D-P1)×[(X S1 -P1)-(X S2 -P2)] / (P2-P1);

[0082] When P2≤D≤P3, the calibration function is:

[0083] P = K × D + X S2 -P2-(K×D-P2)×[(X S2 -P2)-(X S3 -P3)] / (P3-P2);

[0084] When D≥P3, the calibration function is: P=K×D+(X SH -K×D)×(X S3 -P3) / (X SH -P3);

[0085] In the formula, K represents the proportionality coefficient, K = (P SH -P SL ) / P SH D represents the measured pressure value of the target silicon pressure sensor.

[0086] In other words, see Figure 5 When N=5, it can be considered that 5-point calibration has been performed: the error of the calibration function can be reduced to 0.04% compared with the measured pressure curve.

[0087] It should be noted that users can choose the value of N according to their actual needs. The larger the value of N, the greater the computational workload, but the higher the accuracy after linear calibration.

[0088] S2 performs temperature compensation on the target silicon voltage sensor.

[0089] S2 includes:

[0090] S2.1, Place the target silicon voltage sensor successively at M preset temperatures T1 to T2. M Below, and at the m-th preset temperature T m X is applied sequentially to the target silicon voltage sensor. SL X SH The target silicon pressure sensor detects the corresponding value.

[0091] Among them, X SL X represents the zero-point pressure value of the target silicon pressure sensor. SH The target silicon pressure sensor's full-scale pressure value. For the target silicon voltage sensor in X SL T m The measured pressure value under the pressure, For X SH The target silicon voltage sensor in X SL T m The measured pressure value.

[0092] S2.2, Select the two preset temperatures T that are closest to T0 from the M preset temperatures. p T q Among them, T P For the p-th preset temperature, T q T is the qth preset temperature; p ≤T0, T q ≥T0; S2.3, based on T p T q Based on the data, a set of compensation functions is constructed to obtain the temperature-compensated pressure measurement value P′.

[0093] Specifically, the compensation function set is as follows:

[0094]

[0095] In the formula, ΔT represents the temperature difference;

[0096] Indicates the target silicon voltage sensor in X SL T p Measured pressure value;

[0097] Indicates the target silicon voltage sensor in X SL T q Measured pressure value;

[0098] K p T represents p The K value below;

[0099] K q T represents q The K value below.

[0100] Similar to linear calibration, users can select the value of M based on their specific needs. A larger value for M results in a greater computational workload but also higher accuracy after temperature compensation.

[0101] Additionally, see Figure 6 It showed Figure 1 After temperature compensation, the pressure linear curves at two different temperatures (temperature 1 and temperature 2) show that the temperature drift error decreased from 2% to 0.01%.

[0102] Based on the above processing, the measured value of the target silicon pressure sensor can be corrected to obtain accurate data.

[0103] Example 2

[0104] This embodiment 2 designs and discloses a measurement accuracy compensation circuit for a silicon voltage sensor to apply the method of embodiment 1.

[0105] See Figure 7 In summary, the measurement accuracy compensation circuit includes: a target silicon voltage sensor, a temperature detection module, a signal amplification module, an STC microcontroller, and peripheral functional circuits.

[0106] The temperature detection module is integrated into the target silicon voltage sensor and is used to detect the temperature T0 at which the target silicon voltage sensor is actually used.

[0107] The signal amplification module is used to amplify the detection signal from the target silicon pressure sensor to obtain the measured pressure value.

[0108] The STC microcontroller is connected to the temperature detection module and the signal amplification module, and is used to compensate the measurement accuracy of the target silicon voltage sensor according to the silicon voltage sensor measurement accuracy compensation method disclosed in Example 1.

[0109] The peripheral functional circuits are used to ensure the normal operation of the target silicon voltage sensor, temperature detection module, signal amplification module, and STC microcontroller.

[0110] The peripheral functional circuitry includes a power supply module and a voltage regulator module. The power supply module converts +24V to +3.3V and provides power. The voltage regulator module converts +3.3V to +2.5V and provides power, as well as a precise reference for the STC microcontroller's A / D conversion.

[0111] Of course, the peripheral functional circuitry can also provide other functions, including: a data display module, a button operation module, and an RS485 communication module. The data display module is electrically connected to the STC microcontroller and displays the pressure measurement value after accuracy compensation by the STC microcontroller. The button operation module is electrically connected to the STC microcontroller and extends the STC microcontroller's button functionality. The RS485 communication module is electrically connected to the STC microcontroller and extends the STC microcontroller's RS485 interface.

[0112] The following is an explanation of each part:

[0113] 1. See Figure 8 In this embodiment 2, the STC microcontroller used is the STC8H, which has a total of 48 pins:

[0114] Set pin 1 to empty;

[0115] Pin 2 is designated as the O terminal, also known as the O terminal;

[0116] Pin 3 is designated as the D terminal, also known as the d terminal;

[0117] Pin 4 is designated as the E terminal, also known as the e terminal;

[0118] Pins 5 through 8 should be left unused.

[0119] Pin 9 is designated as D4, also known as P1.5-D4.

[0120] Pin 10 is designated as the AD1 terminal, also known as the P1.6-AD1+ terminal;

[0121] Pin 11 is designated as the AD2 terminal, also known as the P1.7-AD2- terminal;

[0122] Pin 12 is designated as the AD3 terminal, also known as the P1.3-TAD3 terminal;

[0123] Pins 13 and 14 should be left empty.

[0124] Pins 15 and 17 are used together: Pin 15 is connected to the first terminal of capacitor C6, and pin 17 is connected to the second terminal of capacitor C6; the first terminal of C6 is connected to the +3.3V power supply, and the second terminal is connected to GND.

[0125] Pin 16 is connected to a +2.5V power supply. It should be noted that this pin is connected to a +2.5V power supply to provide a precise reference for the STC microcontroller's A / D conversion.

[0126] Pin 18 should be left empty;

[0127] Pins 19 and 20 are used together: pin 19 connects to the second terminal of J5, and pin 20 connects to the third terminal of J5; the first terminal of J5 is connected to the +3.3V power supply, and the fourth terminal is connected to GND; J5 is the STC microcontroller program download interface.

[0128] Pin 21 is designated as terminal K1, also known as terminal K1-P3.2.

[0129] Pin 22 is designated as terminal K2, also known as terminal K2-P3.3;

[0130] Pin 23 is designated as terminal K3, also known as terminal K2-P3.4;

[0131] Pin 24 is designated as the K0 terminal, also known as the K0-P5.0 terminal;

[0132] Pins 25-30 should be left unused.

[0133] Pin 31 is used as the RX terminal, also known as RX-P4.3 or P4.3-RX terminal;

[0134] Pin 32 is designated as the TX terminal, also known as the TX-P4.4 or P4.4-TX terminal;

[0135] Pins 33-38 should be left unused.

[0136] Pin 39 is designated as the RE terminal, also known as RE-P2.6 or P2.6.

[0137] Pin 40 should be left empty;

[0138] Pin 41 is designated as the D2 terminal, also known as the D2-P4.5 terminal;

[0139] Pin 42 is designated as the D1 terminal, also known as the D1-P4.6 terminal;

[0140] Pin 43 is designated as the C terminal, also known as the C terminal;

[0141] Pin 44 is designated as the G terminal, also known as the g terminal;

[0142] Pin 45 is designated as terminal A, also known as terminal a;

[0143] Pin 46 is designated as the F terminal, also known as the f terminal;

[0144] Pin 47 is designated as terminal B, also known as terminal b;

[0145] Pin 48 is designated as the D3 terminal, also known as the D3-P5.2 terminal.

[0146] 2. See Figure 9 The target silicon voltage sensor PC has its power supply terminal connected to a +2.5V power supply and its ground terminal connected to GND. The target silicon voltage sensor PC has two signal output terminals: +S and -S.

[0147] See Figure 4 The temperature detection module is integrated into the target silicon pressure sensor and is used to detect the temperature T0 at which the target silicon pressure sensor is actually used.

[0148] The temperature detection module includes: a temperature detection diode DT, a resistor R1, and a capacitor C9. The first terminal of R1 is connected to a +3.3V power supply, and the second terminal is connected to the AD3 terminal. The positive terminal of DT is connected to the AD3 terminal, and the negative terminal is connected to GND. The first terminal of C9 is connected to the AD3 terminal, and the negative terminal is connected to GND.

[0149] The DT performs temperature detection and reads the data via the STC8H through the AD3 terminal.

[0150] 3. See Figure 10 The power supply and voltage regulation module includes: diode D2, TVS diode D3, capacitor C2, linear regulator U2, capacitor C1, GDTN diode D4, capacitor C3, resistor R7, and LED.

[0151] Connect the first terminal of R7 to the +3.3V power supply. Connect the positive terminal of the LED to the second terminal of R7, and the negative terminal to GND.

[0152] Connect the positive terminal of D2 to the +24V power supply and the negative terminal to VCC. Connect the negative terminal of D3 to the negative terminal of D2 and the positive terminal to GND. Connect the first terminal of C2 to VCC and the second terminal to GND. Connect the input terminal of U2 to VCC, the output terminal to the +3.3V power supply, and the ground terminal to GND. Connect the first terminal of C1 to the +3.3V power supply and the second terminal to GND.

[0153] One end of D4 is connected to GND. The first end of C3 is connected to GND, and the second end is connected to the other end of D4. The second end of C3 also serves as the KE terminal.

[0154] 3. See Figure 11 The high-precision reference module includes: a three-terminal parallel voltage regulator U5 and a resistor R20. The first terminal of R20 is connected to a +3.3V power supply; the first terminal of U5 is connected to the second terminal, and the third terminal is connected to GND. The second terminal of U5 is connected to a +2.5V power supply.

[0155] 4. See Figure 12 The signal amplification module includes: capacitors C7, C8, C4, and C5; resistors R2, R3, R4, R5, and R6; and amplifier U8.

[0156] C7's first terminal is connected to +S, and its second terminal is connected to -S; C8's first terminal is connected to -S, and its second terminal is connected to GND; C4's first terminal is connected to AD1, and its second terminal is connected to GND; C5's first terminal is connected to GND, and its second terminal is connected to AD2.

[0157] The first end of R2 is connected to the second end of AD1; the first end of R4 is connected to the second end of R2; the first end of R6 is connected to the second end of R4; the first end of R5 is connected to the second end of R6; the first end of R3 is connected to the second end of R5; and the second end of R3 is connected to the AD2 end.

[0158] The first terminal of U8 is connected to the second terminal of R2, the second terminal is connected to the second terminal of R4, the third terminal is connected to the +S terminal, the fourth terminal is connected to GND, the fifth terminal is connected to the -S terminal, the sixth terminal is connected to the second terminal of R6, the seventh terminal is connected to the second terminal of R5, and the eighth terminal is connected to the +3.3V power supply.

[0159] 5. See Figure 13 The RS485 communication module includes: transceiver U4, RS485 communication port J2, resistor R16, resistor R17, and resistor R18.

[0160] Connect the first terminal of U4 to the RX terminal, the second terminal to the RE terminal, the third terminal to the RE terminal, the fourth terminal to the TX terminal, the fifth terminal to GND, and the eighth terminal to the +3.3V power supply.

[0161] The first terminal of J2 is connected to GND, the second terminal is connected to the +24V power supply, the third terminal is connected to the seventh terminal of U4, and the fourth terminal is connected to the sixth terminal of U4.

[0162] Connect the first terminal of R16 to the sixth terminal of U4, and the second terminal to the third terminal of J2. Connect the first terminal of R17 to the +3.3V power supply, and the second terminal to the sixth terminal of U4. Connect the first terminal of R18 to GND, and the second terminal to the seventh terminal of U4.

[0163] 6. See Figure 14 The data display module includes: an LED digital tube and resistors R8 to R15. The first end of the LED digital tube is connected to the E terminal via R9, the second end is connected to the D terminal via R8, the third end is connected to the O terminal via R10, the fourth end is connected to the C terminal via R11, the fifth end is connected to the G terminal via R12, the sixth end is connected to the D4 terminal, the seventh end is connected to the B terminal via R15, the eighth end is connected to the D3 terminal, the ninth end is connected to the D2 terminal, the tenth end is connected to the F terminal via R14, the eleventh end is connected to the A terminal via R13, and the twelfth end is connected to the D1 terminal.

[0164] The button operation module includes: micro button switch SW1, micro button switch SW2, and micro button switch SW3. One end of SW1 is connected to the KO terminal, and the other end is connected to K1. One end of SW2 is connected to the KO terminal, and the other end is connected to K2. One end of SW3 is connected to the KO terminal, and the other end is connected to K3. Among them, SW1 to SW3 are instrument operation buttons used to control the STC microcontroller.

[0165] For the selection of the above components, please refer to [reference needed]. Figures 3-8 Of course, other specifications of components can also be used, but their specifications must be matched to the corresponding functions.

[0166] Based on the above circuit structure, the voltage regulator module provides a regulated power supply to the target silicon voltage sensor. The target silicon voltage sensor outputs the acquired signal through the +S and -S terminals, which is then differentially amplified by the signal amplification module, where the amplification factor A = (R20 + R21) / R19. The amplified differential signal is then provided to the AD1 and AD2 terminals of the STC microcontroller for the STC microcontroller to read. At the same time, the temperature signal of DT is read by the AD3 terminal of the STC microcontroller.

[0167] The STC microcontroller performs measurement accuracy compensation according to the method in Example 1, and the final result is displayed by the data display module, which also provides RS485 standard signal output. Furthermore, relevant parameters of the STC microcontroller can be modified via RS485.

[0168] Example 3

[0169] This embodiment 3 discloses a measurement accuracy compensation motherboard for a silicon voltage sensor. The measurement accuracy compensation circuit of the silicon voltage sensor of embodiment 2 is printed on the motherboard.

[0170] Generally, the pins of this type of motherboard include: power supply pin, ground pin, and RS485 pin.

[0171] The power supply pin is used to connect to a +24V power supply. The ground pin is used to connect to GND. The RS485 pin is used to connect to J2.

[0172] This motherboard can also be fitted with a casing for protection. Additionally, referring to the above, since the second terminal of C3 is the KE terminal, the motherboard should also have additional casing pins for connecting the KE terminal. This allows the surge pulse to be discharged through the motherboard's casing by connecting to the casing via these casing pins.

[0173] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0174] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for compensating the measurement accuracy of a silicon voltage sensor, characterized in that, It is used to compensate for the measurement accuracy of the target silicon pressure sensor; the target silicon pressure sensor integrates a temperature detection module; The methods for measurement accuracy compensation include: S1, perform linear calibration on the target silicon voltage sensor; S2, temperature compensation for the target silicon voltage sensor; S1 includes: S1.1, Obtain the temperature T0 of the target silicon pressure sensor during actual use; Keeping T0 constant, apply pressure sequentially to the target silicon voltage sensor. N A standard pressure value is detected by the target silicon pressure sensor. N Measured pressure values; of which 5 ≥ N ≥3; S1.2, according to T0 N A standard pressure value, N A calibration function is constructed using measured pressure values ​​to obtain linearly calibrated pressure measurements. P ; S2 includes: S2.1, Place the target silicon voltage sensor successively at M preset temperatures T1~T M Below, and at the m-th preset temperature T m X is applied sequentially to the target silicon voltage sensor. SL X SH The target silicon pressure sensor detects the corresponding value. , m∈[1,M]; Among them, X SL X represents the zero-point pressure value of the target silicon pressure sensor. SH The target silicon pressure sensor's full-scale pressure value. For the target silicon voltage sensor in X SL , T m The measured pressure value under the pressure, For X SH The target silicon voltage sensor in X SL , T m Measured pressure value; S2.2, from M Select the two preset temperatures T0 that are closest to T0 from the preset temperatures. p T q Among them, T P For the first p A preset temperature, T q For the first q A preset temperature; T p ≤T0, T q ≥T0; S2.3, according to T p T q Based on the data, a set of compensation functions is constructed to obtain the temperature-compensated pressure measurement value. ; In S1.2, when N=3, the three standard pressure values ​​include: X SL X SH X S1 ; where X SL X represents the zero-point pressure value of the target silicon pressure sensor. SH X represents the full-scale pressure value of the target silicon pressure sensor. S1 The pressure value is within the range of the target silicon pressure sensor; X SL <X S1 <X SH ; The three measured pressure values ​​include: P SL P SH P1; where P SL For the target silicon voltage sensor at T0, X SL The measured pressure value under the following conditions, P SH For the target silicon voltage sensor at T0, X SH The measured pressure value under the following conditions, P1 is the target silicon pressure sensor at T0, X S1 Measured pressure value under; P SL <P S1 <P SH ; Therefore: when D≤P1, the calibration function is ; When D≥P1, the calibration function is: ; In the formula, K represents the proportionality coefficient. D represents the measured pressure value of the target silicon pressure sensor; In S2.3, the compensation function set is as follows: ； In the formula, Indicates the temperature difference value; Indicates the target silicon voltage sensor in X SL , T p Measured pressure value; Indicates the target silicon voltage sensor in X SL , T q Measured pressure value; K p express T p The K value below; K q express T q The K value below.

2. The measurement accuracy compensation method for the silicon voltage sensor according to claim 1, characterized in that, In S1.2, when N=4, the four standard pressure values ​​include: X SL X SH X S1 X S2 ; where X SL X represents the zero-point pressure value of the target silicon pressure sensor. SH X represents the full-scale pressure value of the target silicon pressure sensor. S1 X S2 All are pressure values ​​within the range of the target silicon pressure sensor; X SL <X S1 <X S2 <X SH ; The four measured pressure values ​​include: P SL P SH P1, P2; where P SL For the target silicon voltage sensor at T0, X SL The measured pressure value under the following conditions, P SH For the target silicon voltage sensor at T0, X SH The measured pressure value under the following conditions, P1 is the target silicon pressure sensor at T0, X S1 The measured pressure value under the following conditions, P2 is the target silicon pressure sensor at T0, X S2 Measured pressure value under; P SL <P1<P2<P SH ; Therefore: when D≤P1, the calibration function is ; When P1≤D≤P2, the calibration function is: ； When D≥P2, the calibration function is: ; In the formula, K represents the proportionality coefficient. D represents the measured pressure value of the target silicon pressure sensor.

3. The measurement accuracy compensation method for the silicon voltage sensor according to claim 1, characterized in that, In S1.2, when N=5, the five standard pressure values ​​include: X SL X SH X S1 X S2 X S3 ; where X SL X represents the zero-point pressure value of the target silicon pressure sensor. SH X represents the full-scale pressure value of the target silicon pressure sensor. S1 X S2 X S3 All are pressure values ​​within the range of the target silicon pressure sensor; X SL <X S1 <X S2 <X S3 <X SH ; The five measured pressure values ​​include: P SL P SH P1, P2, P3; where P SL For T0, X SL The measured pressure value of the target silicon pressure sensor, P SH For the target silicon voltage sensor at T0, X SH The measured pressure value under the following conditions, P1 is the target silicon pressure sensor at T0, X S1 The measured pressure value under the following conditions, P2 is the target silicon pressure sensor at T0, X S2 The measured pressure value under the following conditions; P3 is the target silicon pressure sensor at T0, X S3 Measured pressure value under; P SL <P1<P2<P3<P SH ; Therefore: when D≤P1, the calibration function is ; When P1≤D≤P2, the calibration function is: ； When P2≤D≤P3, the calibration function is: ； When D≥P3, the calibration function is: ; In the formula, K represents the proportionality coefficient. D represents the measured pressure value of the target silicon pressure sensor.

4. A measurement accuracy compensation circuit for a silicon voltage sensor, characterized in that, include: Target silicon voltage sensor, The temperature detection module, which is integrated into the target silicon voltage sensor, is used to detect the temperature T0 at which the target silicon voltage sensor is actually used. The signal amplification module is used to amplify the detection signal of the target silicon pressure sensor to obtain the measured pressure value; An STC microcontroller, connected to a temperature detection module and a signal amplification module, is used to compensate the measurement accuracy of the target silicon voltage sensor according to the measurement accuracy compensation method for silicon voltage sensors as described in any one of claims 1-3. as well as The peripheral functional circuitry is used to ensure the normal operation of the target silicon voltage sensor, temperature detection module, signal amplification module, and STC microcontroller.

5. The measurement accuracy compensation circuit for the silicon voltage sensor according to claim 4, characterized in that, The peripheral functional circuit includes: The power supply regulator module is used to convert +24V power to +3.3V power and provide power. The high-precision reference module is used to convert +3.3V power to +2.5V power, provide power, and provide a precise reference for the STC microcontroller's A / D conversion.

6. The measurement accuracy compensation circuit for the silicon voltage sensor according to claim 5, characterized in that, The peripheral functional circuit also includes: The data display module is electrically connected to the STC microcontroller and is used to display the pressure measurement value after the STC microcontroller's measurement accuracy has been compensated. as well as The button operation module is electrically connected to the STC microcontroller and is used to extend the button control function of the STC microcontroller.

7. The measurement accuracy compensation circuit for the silicon voltage sensor according to claim 6, characterized in that, The peripheral functional circuit also includes: The RS485 communication module is electrically connected to the STC microcontroller and is used to expand the STC microcontroller to have an RS485 interface.

8. A measurement accuracy compensation motherboard for a silicon voltage sensor, characterized in that, The motherboard is printed with a measurement accuracy compensation circuit for the silicon voltage sensor as described in any one of claims 5-7.

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