Vibrating wire signal conditioning circuit

Abstract

The utility model discloses a vibrating wire signal conditioning circuit in the field of power electronics, which comprises a filter protection circuit, the filter protection circuit is connected with an excitation power supply circuit and a clamping amplification circuit, and the clamping amplification circuit is connected with an operational amplifier power supply circuit and a hysteresis comparison circuit. Vibrating wire signals of a vibrating wire sensor are received through the filtering protection circuit, the signals are filtered and then output to the clamping amplification circuit, it is ensured that the amplitude of the vibrating wire is not too large, the vibrating wire signals are amplified and then converted into digital signals through the hysteresis comparison circuit, the digital signals are finally sent to the single-chip microcomputer to be sampled, and the output digital signals are good in stability and high in reliability. The fidelity is high, the linearity is good, and the ADC sampling result is more accurate.

Description

Technical Field

[0001] The utility model relates to a vibrating wire signal conditioning circuit in the field of power electronics. Background Art

[0002] The working principle of a vibrating wire sensor is based on the resonance phenomenon of a wire. When a force acts on the wire in the sensor, it will vibrate, which causes a change in the resonance frequency of the sensor, thereby reflecting the magnitude of the external force. Usually, one end of the wire is fixed, and the other end is connected to the measuring element of the sensor. When an external force acts on the wire, the wire will vibrate, and the sensor will measure the vibration signal and convert it into a corresponding electrical signal. However, vibrating wire sensors also have some disadvantages: 1. Affected by temperature: In a high-temperature environment, the performance of the sensor may be affected. 2. Signal attenuation: The signal of the sensor may attenuate during transmission, resulting in inaccurate measurement results. Therefore, it is necessary to convert the vibrating wire signal output by the vibrating wire sensor into a digital signal and transmit it to a single-chip microcomputer for ADC sampling to monitor the vibrating wire signal in real time. However, the digital signal output by the vibrating wire signal conditioning circuit in the prior art has insufficient stability and fidelity, resulting in poor ADC sampling results. Content of the Utility Model

[0003] The purpose of the utility model is to provide a vibrating wire signal conditioning circuit, which outputs a digital signal with good stability, high fidelity and good linearity, making the ADC sampling result more accurate.

[0004] To achieve the above purpose, the utility model provides a vibrating wire signal conditioning circuit, which includes a filter protection circuit. The filter protection circuit is connected to an excitation power supply circuit and a clamping amplification circuit, and the clamping amplification circuit is connected to an operational amplifier power supply circuit and a hysteresis comparison circuit.

[0005] Compared with the prior art, the beneficial effect of the utility model is that the filter protection circuit receives the vibrating wire signal of the vibrating wire sensor, filters the signal and then outputs it to the clamping amplification circuit to ensure that the vibrating wire amplitude will not be too large, and amplifies the vibrating wire signal. Then, through the hysteresis comparison circuit, it is converted into a digital signal and finally given to the single-chip microcomputer for sampling. The output digital signal has good stability, high fidelity and good linearity, making the ADC sampling result more accurate.

[0006] As a further improvement of the present utility model, the filtering and protection circuit includes a socket J1, which is connected to the vibrating wire sensor. The pin 1 of the socket J1 is connected to the pin 2 of the TVS diode D5. The pin 2 of the socket J1 is respectively connected to the pin 1 of the TVS diode D5 and the emitter of the triode Q2. The base of the triode Q2 is connected to the excitation signal control pin WCTRL of the single-chip microcomputer through the resistor R9. The collector of the triode Q2 is respectively connected to one end of the resistor R1 and the base of the triode Q1 through the resistor R3. The emitter of the triode Q1 is respectively connected to the other end of the resistor R1, one end of the capacitor C1 and the excitation power supply circuit. The other end of the capacitor C1 is grounded. The collector of the triode Q1 is respectively connected to the pin 1 of the socket J1, one end of the resistor R7 and the negative pole of the anti-reverse diode D3. The positive pole of the anti-reverse diode D3 is respectively connected to the pin 1 of the TVS diode D5 and one end of the capacitor C6 and grounded. The other end of the capacitor C6 is respectively connected to the other end of the resistor R7 and one end of the capacitor C3. The other end of the capacitor C3 is connected to the clamping and amplifying circuit.

[0007] In this way, the TVS diode D5 can protect the vibrating wire signal output by the vibrating wire sensor, and the anti-reverse diode D3 protects the coil energy inside the vibrating wire sensor, thereby protecting the safety of the circuit. The vibrating wire signal filters out high-frequency signals through the resistor R7 and the capacitor C6, and the capacitor C3 filters out the DC signal in the vibrating wire signal, thereby obtaining the desired low-frequency vibrating wire signal.

[0008] As a further improvement of the present utility model, the clamping and amplifying circuit includes a diode D1. The negative pole of the diode D1 is connected to the operational amplifier power supply circuit. The positive pole of the diode D1 is respectively connected to the other end of the capacitor C3, one end of the resistor R8 and the negative pole of the diode D2. The positive pole of the diode D2 is connected to one end of the capacitor C5 and grounded. The other end of the capacitor C5 is respectively connected to the other end of the resistor R8 and the pin 2 of the operational amplifier U1A. A resistor R2 is connected between the pin 2 and the pin 1 of the operational amplifier U1A. The pin 3 of the operational amplifier U1A is connected to one end of the resistor R12. The other end of the resistor R12 is connected to the operational amplifier power supply circuit. The pin 4 of the operational amplifier U1A is connected to the operational amplifier power supply circuit. The pin 11 of the operational amplifier U1A is grounded. The pin 1 of the operational amplifier U1A is connected to the pin 13 of the operational amplifier U1D through the capacitor C4 and the resistor R11. A resistor R5 is connected between the pin 13 and the pin 14 of the operational amplifier U1D. The resistor R5 is connected in parallel with the capacitor C2. The pin 12 of the operational amplifier U1D is connected to one end of the resistor R14. The other end of the resistor R14 is connected to the operational amplifier power supply circuit. The pin 14 of the operational amplifier U1D is connected to the hysteresis comparison circuit.

[0009] In this way, D1 and D2 play a clamping role, making the amplitude of the vibrating string between 0 and 3.3V. The AC signal of the vibrating string passes through the amplifier circuit composed of R8, R2, and U1A. The 3rd pin of U1A is the center voltage of the vibrating string signal. After amplifying the vibrating string signal by 1000 times, the phase is opposite to the original one. C4 removes the DC signal of the vibrating string signal. The AC signal of the vibrating string passes through the amplifier circuit composed of R11, R5, and U1D, and the phase is the same as the original one, obtaining the vibrating string AC signal with the amplified string amplitude between 0 and 3.3V as required.

[0010] As a further improvement of the present utility model, the hysteresis comparison circuit includes an operational amplifier U1C. The 10th pin of the operational amplifier U1C is connected to the 14th pin of the operational amplifier U1D through a resistor R13. A resistor R15 is connected between the 10th pin and the 8th pin of the operational amplifier U1C. The 9th pin of the operational amplifier U1C is connected to one end of a resistor R6, and the other end of the resistor R6 is connected to the operational amplifier power supply circuit. The 8th pin of the operational amplifier U1C is connected to one end of a resistor 10, and the other end of the resistor 10 is connected to the SAMP2 pin of the single-chip microcomputer.

[0011] In this way, the vibrating string signal is converted into a digital signal and given to the single-chip microcomputer for ADC sampling.

[0012] As a further improvement of the present utility model, the operational amplifier power supply circuit includes a step-down chip U2. The 3rd pin of the step-down chip U2 is connected to the 5V power supply and grounded through a capacitor C17. The 1st pin of the step-down chip U2 is grounded. The 2nd pin of the step-down chip U2 is respectively connected to one end of a capacitor C7 and one end of a capacitor C8. The other end of the capacitor C7 and the other end of the capacitor C8 are connected and grounded. One end of the capacitor C8 is connected to the negative pole of a diode D1 and the 4th pin of the operational amplifier U1A. One end of the capacitor C8 is also connected to one end of a resistor R16. The other end of the resistor R16 is connected to one end of a resistor R17, one end of a capacitor C9, and one end of a capacitor C10. The other end of the resistor R17 is connected to the other end of the capacitor C9 and the other end of the capacitor C10 and grounded. One end of the capacitor C10 is connected to the 5th pin of the operational amplifier U1B. The 6th pin and the 7th pin of the operational amplifier U1B are connected. The 7th pin of the operational amplifier U1B is respectively connected to the other end of a resistor R12, the other end of a resistor R14, and the other end of a resistor R6.

[0013] In this way, a 3.3V voltage is output through the step-down chip U2, and then a signal bias voltage of 1.65V is output by the operational amplifier U1B.

[0014] As a further improvement of the present utility model, the excitation power supply circuit includes a boost chip U3. The 5th pin of the boost chip U3 is respectively connected to the 5V power supply and the positive electrode of the capacitor C11. The negative electrode of the capacitor C11 is grounded. The 4th pin of the boost chip U3 is connected to the POWEREN pin of the single-chip microcomputer via the resistor R19. An inductor L1 is connected between the 5th pin and the 1st pin of the boost chip U3. The 2nd pin of the boost chip U3 is grounded. The 1st pin of the boost chip U3 is connected to the positive electrode of the anti-reverse diode D4. The negative electrode of the anti-reverse diode D4 is connected to one end of the resistor R18. The other end of the resistor R18 is respectively connected to one end of the resistor R20 and the 3rd pin of the boost chip U3. The other end of the resistor R20 is connected to the 3rd pin of the MOS transistor Q3. The 2nd pin of the MOS transistor Q3 is grounded and connected to the 3rd pin of the boost chip U3 via the resistor R21. The 1st pin of the MOS transistor Q3 is connected to the PVCTRL pin of the single-chip microcomputer via the resistor R22. One end of the resistor R18 is connected to the positive electrodes of the capacitors C13, C14, and C15. The negative electrodes of the capacitors C13, C14, and C15 and the negative electrode of the capacitor C12 are connected and grounded. The positive electrode of the capacitor C12 is connected to one end of the capacitor C1.

[0015] In this way, the excitation voltage required by the vibrating wire sensor is generated through the excitation power supply circuit. There are two gear selections. By default, it is 25V. It is also possible to output a high level through the PVCTRL pin of the single-chip microcomputer, so that the MOS transistor Q3 is turned on, the resistors R21 and R20 are connected in parallel, and thus the finally output excitation voltage is switched to 36V. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is the main circuit diagram of the present utility model.

[0017] Figure 2 It is the operational amplifier power supply circuit diagram of the present utility model.

[0018] Figure 3 It is the excitation power supply circuit diagram of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] The present utility model will be further described below with reference to the accompanying drawings:

[0020] As Figures 1 - 3 shown, a vibrating wire signal conditioning circuit includes a filtering and protection circuit. The filtering and protection circuit is connected to the excitation power supply circuit and the clamping and amplifying circuit. The clamping and amplifying circuit is connected to the operational amplifier power supply circuit and the hysteresis comparison circuit.

[0021] The filtering protection circuit includes socket J1. Socket J1 is connected to the vibrating wire sensor. Pin 1 of socket J1 is connected to pin 2 of TVS diode D5. Pin 2 of socket J1 is respectively connected to pin 1 of TVS diode D5 and the emitter of triode Q2. The base of triode Q2 is connected to the excitation signal control pin WCTRL of the single-chip microcomputer via resistor R9. The collector of triode Q2 is respectively connected to one end of resistor R1 and the base of triode Q1 via resistor R3. The emitter of triode Q1 is respectively connected to the other end of resistor R1, one end of capacitor C1 and the excitation power supply circuit. The other end of capacitor C1 is grounded. The collector of triode Q1 is respectively connected to pin 1 of socket J1, one end of resistor R7 and the negative pole of the reverse protection diode D3. The positive pole of the reverse protection diode D3 is respectively connected to pin 1 of TVS diode D5 and one end of capacitor C6 and grounded. The other end of capacitor C6 is respectively connected to the other end of resistor R7 and one end of capacitor C3. The other end of capacitor C3 is connected to the clamping and amplifying circuit.

[0022] The clamping and amplifying circuit includes diode D1. The negative pole of diode D1 is connected to the operational amplifier power supply circuit. The positive pole of diode D1 is respectively connected to the other end of capacitor C3, one end of resistor R8 and the negative pole of diode D2. The positive pole of diode D2 is connected to one end of capacitor C5 and grounded. The other end of capacitor C5 is respectively connected to the other end of resistor R8 and pin 2 of operational amplifier U1A. A resistor R2 is connected between pin 2 and pin 1 of operational amplifier U1A. Pin 3 of operational amplifier U1A is connected to one end of resistor R12. The other end of resistor R12 is connected to the operational amplifier power supply circuit. Pin 4 of operational amplifier U1A is connected to the operational amplifier power supply circuit. Pin 11 of operational amplifier U1A is grounded. Pin 1 of operational amplifier U1A is connected to pin 13 of operational amplifier U1D via capacitor C4 and resistor R11; A resistor R5 is connected between pin 13 and pin 14 of operational amplifier U1D. Resistor R5 is in parallel with capacitor C2. Pin 12 of operational amplifier U1D is connected to one end of resistor R14. The other end of resistor R14 is connected to the operational amplifier power supply circuit. Pin 14 of operational amplifier U1D is connected to the hysteresis comparison circuit.

[0023] The hysteresis comparison circuit includes operational amplifier U1C. Pin 10 of operational amplifier U1C is connected to pin 14 of operational amplifier U1D via resistor R13. A resistor R15 is connected between pin 10 and pin 8 of operational amplifier U1C. Pin 9 of operational amplifier U1C is connected to one end of resistor R6. The other end of resistor R6 is connected to the operational amplifier power supply circuit. Pin 8 of operational amplifier U1C is connected to one end of resistor 10. The other end of resistor 10 is connected to the SAMP2 pin of the single-chip microcomputer.

[0024] The operational amplifier power supply circuit includes a step-down chip U2. The 3rd pin of the step-down chip U2 is connected to the 5V power supply and grounded through a capacitor C17. The 1st pin of the step-down chip U2 is grounded. The 2nd pin of the step-down chip U2 is respectively connected to one end of a capacitor C7 and one end of a capacitor C8. The other end of the capacitor C7 and the other end of the capacitor C8 are connected together and grounded. One end of the capacitor C8 is connected to the negative pole of a diode D1 and the 4th pin of an operational amplifier U1A. One end of the capacitor C8 is also connected to one end of a resistor R16. The other end of the resistor R16 is connected to one end of a resistor R17, one end of a capacitor C9, and one end of a capacitor C10. The other end of the resistor R17 is connected to the other end of the capacitor C9 and the other end of the capacitor C10 and grounded. One end of the capacitor C10 is connected to the 5th pin of an operational amplifier U1B. The 6th pin and the 7th pin of the operational amplifier U1B are connected together. The 7th pin of the operational amplifier U1B is respectively connected to the other end of a resistor R12, the other end of a resistor R14, and the other end of a resistor R6.

[0025] The excitation power supply circuit includes a boost chip U3. The 5th pin of the boost chip U3 is respectively connected to the 5V power supply and the positive pole of a capacitor C11. The negative pole of the capacitor C11 is grounded. The 4th pin of the boost chip U3 is connected to the POWEREN pin of the single-chip microcomputer through a resistor R19. An inductor L1 is connected between the 5th pin and the 1st pin of the boost chip U3. The 2nd pin of the boost chip U3 is grounded. The 1st pin of the boost chip U3 is connected to the positive pole of an anti-reverse diode D4. The negative pole of the anti-reverse diode D4 is connected to one end of a resistor R18. The other end of the resistor R18 is respectively connected to one end of a resistor R20 and the 3rd pin of the boost chip U3. The other end of the resistor R20 is connected to the 3rd pin of a MOS transistor Q3. The 2nd pin of the MOS transistor Q3 is grounded and connected to the 3rd pin of the boost chip U3 through a resistor R21. The 1st pin of the MOS transistor Q3 is connected to the PVCTRL pin of the single-chip microcomputer through a resistor R22. One end of the resistor R18 is connected to the positive pole of a capacitor C13, the positive pole of a capacitor C14, and the positive pole of a capacitor C15. The negative pole of the capacitor C13, the negative pole of the capacitor C14, the negative pole of the capacitor C15, and the negative pole of a capacitor C12 are connected together and grounded. The positive pole of the capacitor C12 is connected to one end of a capacitor C1.

[0026] In the present utility model, the vibrating wire sensor is connected through a socket J1. The PV+36V is the excitation power supply voltage of the vibrating wire sensor, which is obtained by boosting the 5V voltage through the boost chip U3. When the controllable PVCTRL pin of the single-chip microcomputer outputs a low level, the MOS transistor Q3 is cut off, so that the finally output voltage is the default 25V for use. When the controllable PVCTRL pin of the single-chip microcomputer outputs a high level, the MOS transistor Q3 is turned on, so that the resistors R21 and R20 are in parallel, and thus the output voltage is 36V. The corresponding excitation voltage can be selected according to the model of the vibrating wire sensor. The operational amplifier power supply circuit generates a 3.3V operational amplifier voltage and a 1.65V signal bias voltage for use by the clamping and amplifying circuit.

[0027] The excitation signal control pin WCTRL of the single-chip microcomputer sends a continuous low-voltage pulse signal to the vibrating wire sensor at a frequency close to the self-vibration frequency of the vibrating wire sensor, causing the vibrating wire sensor to generate self-vibration. When there is an excitation signal output, the triode Q2 conducts, and then the triode Q1 conducts. That is, when WCTRL outputs 3.3V, Q1 conducts and the vibrating wire sensor vibrates self-excitedly. When WCTRL outputs 0V, the triodes Q2 and Q1 are cut off, and the vibrating wire sensor does not work.

[0028] After the single-chip microcomputer sends out the excitation signal, the vibrating wire sensor vibrates self-excitedly and outputs a vibrating wire signal. The TVS diode D5 protects the vibrating wire signal, and the anti-reverse diode D3 releases the energy of the internal coil of the vibrating wire sensor. The vibrating wire signal WIRE passes through the low-pass filter circuit composed of R7 and C6 to filter out the high-frequency signals doped inside. The capacitor C3 removes the DC signal of the vibrating wire signal. The diodes D1 and D2 play a clamping role to make the amplitude of the vibrating wire between 0 and 3.3V. The vibrating wire AC signal passes through the amplifier circuit composed of the resistor R8, the resistor R2, and the operational amplifier U1A. The 3rd pin of U1A is the center voltage of the vibrating wire signal. After amplifying the vibrating wire signal by 1000 times, the phase is opposite to the original one. The capacitor C4 removes the DC signal of the vibrating wire signal. The vibrating wire AC signal passes through the amplifier circuit composed of the resistor R11, the resistor R5, and the operational amplifier U1D, and the phase is the same as the original one. The vibrating wire AC signal passes through the hysteresis comparison circuit composed of the resistor R13, R15, and the operational amplifier U1C to convert the vibrating wire signal into a digital signal and send it to the ADC sampling inside the single-chip microcomputer.

[0029] In the above clamping amplifier circuit, the output voltage has the same amplitude and phase as the input voltage, so it has the voltage following characteristic. This characteristic makes the circuit have a lower input impedance and a higher output impedance, making the signal have less loss during transmission and improving the signal fidelity; the amplification factor is constant and will not change with the change of the input signal. This characteristic makes the circuit have better linearity and stability; the bandwidth of the circuit is usually relatively wide, which can adapt to the input of signals with different frequencies, enabling the circuit to process high-frequency signals and improving the signal processing ability; because the input impedance is high, it can reduce the loss of the signal during transmission and improve the signal fidelity.

[0030] The utility model can filter and amplify the vibrating wire signal output by the vibrating wire sensor while the vibrating wire sensor vibrates self-excitedly, and then output a faithful digital signal, so as to input the digital signal into the single-chip microcomputer for ADC sampling, and can better and more intuitively monitor the output signal of the vibrating wire sensor.

[0031] The utility model is not limited to the above embodiments. Based on the technical solutions of the present disclosure, those skilled in the art can make some substitutions and deformations to some of the technical features without creative labor according to the disclosed technical content, and these substitutions and deformations are all within the protection scope of the present utility model.

Claims

1. A vibrating-wire signal conditioning circuit, characterized in that: The invention comprises a filtering protection circuit, wherein the filtering protection circuit is connected with an excitation power supply circuit and a clamping amplifier circuit, and the clamping amplifier circuit is connected with an operational amplifier power supply circuit and a hysteresis comparison circuit.

2. A vibrating-wire signal conditioning circuit according to claim 1, characterized in that: The filter protection circuit includes a socket J1, the socket J1 is connected to the vibrating string sensor, the 1st pin of the socket J1 is connected to the 2nd pin of the TVS diode D5, the 2nd pin of the socket J1 is respectively connected to the 1st pin of the TVS diode D5 and the emitter of the transistor Q2, the base of the transistor Q2 is connected to the excitation signal control pin WCTRL of the single chip computer through the resistor R9, the collector of the transistor Q2 is respectively connected to one end of the resistor R1 and the base of the transistor Q1 through the resistor R3, and the emitter of the transistor Q1 is respectively connected to the resistor R1. The other end of the resistor R1, one end of the capacitor C1 and the excitation power supply circuit are connected, the other end of the capacitor C1 is grounded, the collector of the transistor Q1 is respectively connected to pin 1 of the socket J1, one end of the resistor R7 and the negative electrode of the anti-reverse diode D3, the positive electrode of the anti-reverse diode D3 is respectively connected to pin 1 of the TVS diode D5 and one end of the capacitor C6 and grounded, the other end of the capacitor C6 is respectively connected to the other end of the resistor R7 and one end of the capacitor C3, and the other end of the capacitor C3 is connected to the clamping amplifier circuit.

3. A vibrating-wire signal conditioning circuit according to claim 2, characterized in that: The clamp amplifier circuit includes a diode D1, the cathode of the diode D1 is connected to the operational amplifier power supply circuit, the anode of the diode D1 is respectively connected to the other end of the capacitor C3, one end of the resistor R8 and the cathode of the diode D2, the anode of the diode D2 is respectively connected to one end of the capacitor C5 and grounded, the other end of the capacitor C5 is respectively connected to the other end of the resistor R8 and the 2nd pin of the operational amplifier U1A, a resistor R2 is connected between the 2nd pin and the 1st pin of the operational amplifier U1A, the 3rd pin of the operational amplifier U1A is connected to one end of the resistor R12, the other end of the resistor R12 is connected to the operational amplifier power supply circuit, the 4th pin of the operational amplifier U1A is connected to the operational amplifier power supply circuit, the 11th pin of the operational amplifier U1A is grounded, and the 1st pin of the operational amplifier U1A is connected to the 13th pin of the operational amplifier U1D via the capacitor C4 and the resistor R11; A resistor R5 is connected between pins 13 and 14 of the operational amplifier U1D, and the resistor R5 is connected in parallel with the capacitor C2. Pin 12 of the operational amplifier U1D is connected to one end of the resistor R14, and the other end of the resistor R14 is connected to the operational amplifier power supply circuit. Pin 14 of the operational amplifier U1D is connected to the hysteresis comparator circuit.

4. A vibrating-wire signal conditioning circuit according to claim 3, characterized in that: The hysteresis comparison circuit includes an operational amplifier U1C, wherein the pin 10 of the operational amplifier U1C is connected to the pin 14 of the operational amplifier U1D via a resistor R13, a resistor R15 is connected between the pins 10 and 8 of the operational amplifier U1C, the pin 9 of the operational amplifier U1C is connected to one end of the resistor R6, the other end of the resistor R6 is connected to the operational amplifier power supply circuit, the pin 8 of the operational amplifier U1C is connected to one end of the resistor 10, and the other end of the resistor 10 is connected to the SAMP2 pin of the microcontroller.

5. A vibrating-wire signal conditioning circuit according to claim 4, characterized in that: The operational amplifier power supply circuit includes a step-down chip U2, wherein pin 3 of the step-down chip U2 is connected to a 5V power supply and grounded via capacitor C17, pin 1 of the step-down chip U2 is grounded, pin 2 of the step-down chip U2 is respectively connected to one end of capacitor C7 and one end of capacitor C8, the other end of capacitor C7 is connected to the other end of capacitor C8 and grounded, one end of capacitor C8 is connected to the cathode of diode D1 and pin 4 of operational amplifier U1A, one end of capacitor C8 is also connected to one end of resistor R16, the other end of resistor R16 is connected to one end of resistor R17, one end of capacitor C9 and one end of capacitor C10, the other end of resistor R17 is connected to the other end of capacitor C9 and the other end of capacitor C10 and grounded, one end of capacitor C10 is connected to pin 5 of operational amplifier U1B, pin 6 of operational amplifier U1B is connected to pin 7, and pin 7 of operational amplifier U1B is respectively connected to the other end of resistor R12, the other end of resistor R14 and the other end of resistor R6.

6. A vibrating-wire signal conditioning circuit according to claim 5, characterized in that: The excitation power supply circuit includes a boost chip U3, wherein the 5th pin of the boost chip U3 is respectively connected to a 5V power supply and the positive electrode of a capacitor C11, the negative electrode of the capacitor C11 is grounded, the 4th pin of the boost chip U3 is connected to the POWEREN pin of the single-chip computer via a resistor R19, an inductor L1 is connected between the 5th pin and the 1st pin of the boost chip U3, the 2nd pin of the boost chip U3 is grounded, the 1st pin of the boost chip U3 is connected to the positive electrode of an anti-reverse diode D4, the negative electrode of the anti-reverse diode D4 is connected to one end of a resistor R18, and the other end of the resistor R18 is respectively connected to one end of a resistor R20 and the boost chip Pin 3 of U3 is connected, the other end of resistor R20 is connected to pin 3 of MOS tube Q3, pin 2 of MOS tube Q3 is grounded and connected to pin 3 of boost chip U3 via resistor R21, pin 1 of MOS tube Q3 is connected to pin PVCTRL of microcontroller via resistor R22, one end of resistor R18 is connected to the positive electrode of capacitor C13, the positive electrode of capacitor C14 and the positive electrode of capacitor C15, the negative electrode of capacitor C13, the negative electrode of capacitor C14, the negative electrode of capacitor C15 and the negative electrode of capacitor C12 are connected and grounded, and the positive electrode of capacitor C12 is connected to one end of capacitor C1.

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