A signal acquisition and processing circuit system for a frictional nanogenerator

Abstract

The application discloses a signal acquisition and processing circuit system for a friction nanogenerator, comprising a potentiometer and a voltage follower circuit, a second-order low-pass active filter circuit and a voltage comparison output circuit, wherein the potentiometer and the voltage follower circuit, the second-order low-pass active filter circuit and the voltage comparison output circuit are connected in sequence. By using the application, the signal waveforms generated by friction nanogenerators with different modes and different structures can be collected and regularized, so that the normalization processing of the friction nanogenerator signals can be realized. The application can be widely applied to the field of integrated circuit power management technology as a signal acquisition and processing circuit system for a friction nanogenerator.

Description

Technical Field

[0001] This invention relates to the field of integrated circuit power management technology, and in particular to a signal acquisition and processing circuit system for a triboelectric nanogenerator. Background Technology

[0002] As fundamental equipment for acquiring raw data, sensors have become indispensable in various intelligent applications. Sensor technology has matured significantly over generations. Today, sensors with multiple functions, such as temperature, humidity, gas, light, vibration, and pressure sensors, are already in practical applications. Meanwhile, next-generation micron- and nanometer-scale sensors are under research and development. With the advent of the 5G era, there is an urgent need to address the large-scale deployment of sensors in networks to meet the requirements of comprehensive data acquisition and achieve the goals of the intelligent era. Triboelectric nanogenerators, based on the friction effect, are a novel mechanical energy harvesting device that has been researched and applied in various fields. Their self-powered characteristics effectively solve the problems of short lifespan and environmental pollution associated with traditional active sensors powered by batteries. Triboelectric nanogenerators possess advantages such as a wide variety of materials, low cost, and diverse structures and forms to meet different environmental requirements and are suitable for acquiring various physical quantity signals. A series of triboelectric nanogenerators... The advantages of this technology fully meet the needs of distributed sensors and large-scale low-level signal acquisition in the Internet of Things (IoT) era, further supplementing the development of IoT technology in a series of fields such as smart healthcare, smart homes, smart transportation, and smart cities. Currently, research on the application of triboelectric nanogenerators in the sensing field mainly focuses on the applicable fields, structural forms, and output performance of the devices themselves. Subsequent research on signal conditioning circuits and applications is still in the research and device-specific circuit stage, such as directly using integrated operational amplifiers to follow small-amplitude voltage signals, using transistors to amplify weak currents, and using capacitors to convert the voltage of transferred charges. Each of these dedicated circuits cannot handle the different output ranges of triboelectric nanogenerators, from a few volts to hundreds or even thousands of volts, and they have different delay response times and voltage output waveform shapes, lacking versatility. Summary of the Invention

[0003] To address the aforementioned technical problems, the present invention aims to provide a signal acquisition and processing circuit system for triboelectric nanogenerators. By acquiring and normalizing the signal waveforms generated by triboelectric nanogenerators of different modes and structures, the system can achieve normalization processing of the triboelectric nanogenerator signals.

[0004] The first technical solution adopted in this invention is: a signal acquisition and processing circuit system for a triboelectric nanogenerator, comprising a potentiometer and voltage follower circuit, a second-order low-pass active filter circuit, and a voltage comparison output circuit, wherein the potentiometer and voltage follower circuit, the second-order low-pass active filter circuit, and the voltage comparison output circuit are connected in sequence:

[0005] The potentiometer and voltage follower circuit includes a DC bias circuit, a voltage follower circuit, and a voltage follower circuit.

[0006] The DC bias circuit is used to raise the static operating point voltage from the ground plane reference voltage value to half the supply voltage value and adjust the input impedance of the entire circuit, thereby adjusting the voltage value when the triboelectric nanogenerator generates a signal.

[0007] The voltage follower circuit is used to convert the high output impedance of the triboelectric nanogenerator to a low output impedance and to raise the AC output quiescent point of the triboelectric nanogenerator to half the power supply voltage value.

[0008] The voltage follower circuit achieves impedance conversion by obtaining a preset voltage with an input impedance greater than a preset threshold and outputting a signal with a low output impedance.

[0009] The second-order low-pass active filter circuit is used to filter out high-frequency noise mixed in the output waveform of the triboelectric nanogenerator, so as to achieve a smoother and purer waveform output.

[0010] The voltage comparison output circuit includes a first-stage hysteresis comparator circuit and a second-stage hysteresis comparator circuit.

[0011] The first-stage hysteresis comparator circuit and the second-stage hysteresis comparator circuit are used to compare the output voltage of the comparator to the reference voltage value and output a stable high or low level. When the voltage rises or falls to a certain threshold, the output level is flipped and the current level is output. The first-stage hysteresis comparator circuit and the second-stage hysteresis comparator circuit correspond to two different threshold voltages.

[0012] Furthermore, the potentiometer and voltage follower circuit includes a DC bias circuit, a voltage follower circuit, and a voltage follower circuit including variable resistors R1, R2, and R3, capacitors C1 and C2, and a TLV272ID amplifier U1A. The variable resistors R1, R2, and R3 form the DC bias circuit, the capacitors C1 and C2 form the voltage follower circuit, and the TLV272ID amplifier U1A forms the voltage follower circuit.

[0013] Furthermore, the variable resistor R1 and the TLV272ID amplifier U1A are impedance matched to normalize the triboelectric nanogenerator signal.

[0014] Furthermore, in the potentiometer and voltage follower circuit, the sliding terminal of the variable resistor R1 is connected to the positive terminal of the triboelectric nanogenerator, the first fixed terminal of the variable resistor R1 is connected to the positive terminal of the TLV272ID amplifier U1A, the second fixed terminal of the variable resistor R1 is connected to the second terminal of resistor R2, the first terminal of resistor R3, and the first terminal of capacitor C1, respectively, the second terminal of resistor R3, the second terminal of capacitor C1, and the negative terminal of the triboelectric nanogenerator are connected and grounded, the second pin of the TLV272ID amplifier U1A is connected to the second terminal of capacitor C2 and connected to a high level, the capacitor C2 and the first terminal of the TLV272ID amplifier U1A are grounded, the first terminal of resistor R2 is connected to a high level, and the third pin and the negative terminal of the TLV272ID amplifier U1A are connected to a second-order low-pass active filter circuit.

[0015] Furthermore, the second-order low-pass active filter circuit includes resistors R4, R5, R6, and R7, capacitors C3 and C4, and a TLV272ID amplifier U1B. The first terminal of resistor R4 is connected to the third pin of the TLV272ID amplifier U1A in the potentiometer and voltage follower circuit. The first terminal of resistor R6 is connected to the negative terminal of the TLV272ID amplifier U1A in the potentiometer and voltage follower circuit. The second terminal of resistor R4 is connected to the first terminal of resistor R5 and the first terminal of capacitor C4. The second terminal of resistor R5 is connected to the first terminal of capacitor C3 and the positive terminal of the TLV272ID amplifier U1B. The second terminal of capacitor C3 is connected to the second terminal of resistor R6 and grounded. The second terminal of capacitor C4 is connected to the first terminal of resistor R7 and the negative terminal of the TLV272ID amplifier U1B. The third pin of the TLV272ID amplifier U1B is connected to the voltage comparison output circuit.

[0016] Furthermore, the first-stage hysteresis comparator circuit and the second-stage hysteresis comparator circuit include resistors R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, R19, R20, and R21; capacitors C5, C6, and C7; diode LED1; and LM393DR2G voltage comparator U2A and U2B. In this circuit, resistors R8, R9, R12, R13, R17, R19, R21, capacitors C6 and C7, and LM393DR2G voltage comparator U2A form the first-stage hysteresis comparator circuit, while resistors R10, R11, R14, R15, R16, R18, R20, diode LED1, capacitor C5, and LM393DR2G voltage comparator U2B form the second-stage hysteresis comparator circuit.

[0017] Furthermore, in the voltage comparison output circuit, the first end of resistor R8 is connected to the third pin of the TLV272ID amplifier U1B in the second-order low-pass active filter circuit. The second end of resistor R8 is connected to the first end of resistor R9, the positive terminal of LM393DR2G voltage comparator U2A, the positive terminal of LM393DR2G voltage comparator U2B, the first end of resistor R15, and the first end of resistor R14. The negative terminal of LM393DR2G voltage comparator U2A is connected to the first end of capacitor C6. The second end of capacitor C6 is connected to the second end of resistor R13 and grounded. The second end of resistor R12 is connected to the first end of resistor R13, and the first end of resistor R12 is connected to a high level. The first pin of LM393DR2G voltage comparator U2A is connected to the first end of resistor R17 and the first end of capacitor C7 and connected to a high level. The second pin of LM393DR2G voltage comparator U2A and the second end of capacitor C7 are grounded. The second terminal of resistor R15 is connected to the second terminal of resistor R17, the third pin of LM393DR2G voltage comparator U2A, and the first terminal of resistor R19. The second terminal of capacitor C5 is connected to the second terminal of resistor R11 and grounded. The first terminal of capacitor C5 is connected to the first terminal of resistor R11, the second terminal of resistor R10, and the negative terminal of LM393DR2G voltage comparator U2B. The first terminal of resistor R10 is connected to a high level. The second terminal of resistor R14 is connected to the second terminal of resistor R16, the first terminal of resistor R18, and the third pin of LM393DR2G voltage comparator U2B. The first terminal of resistor R16 is connected to a high level. The second terminal of resistor R18 is connected to the negative terminal of diode LED1 and outputs a low-level digital signal. The positive terminal of diode LED1 is connected to the second terminal of resistor R20. The first terminal of resistor R20 is connected to a high level. The second terminal of resistor R19 is connected to the first terminal of resistor R21 and outputs a high-level digital signal.

[0018] The beneficial effects of the circuit and device of this invention are as follows: By using a series and parallel connection of resistors and variable resistors to change the input reference voltage and input impedance of the circuit, the circuit can acquire signals from triboelectric nanogenerators with different structures and outputs. The wide input voltage range makes it a universal signal processing circuit for triboelectric nanogenerators. Combining existing technology with the low-frequency characteristics of triboelectric nanogenerators, low-pass filtering is performed, which greatly reduces the interference noise generated by the triboelectric nanogenerators and outputs a good analog signal. Furthermore, the addition of two digital output ports further enhances the circuit's anti-interference capability. It can collect and normalize the signal waveforms generated by triboelectric nanogenerators of different modes and structures, and realize the normalization processing of triboelectric nanogenerator signals. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the signal acquisition and processing circuit system for a triboelectric nanogenerator according to the present invention;

[0020] Figure 2 This is a schematic diagram of the static reference voltage for the general analog circuit design of signal acquisition and processing of low-frequency triboelectric nanogenerators, applicable to the present invention.

[0021] Figure 3 This is a schematic diagram simulating the open-circuit voltage and normalized signal of a triboelectric nanogenerator, applicable to signal acquisition of a low-frequency triboelectric nanogenerator according to the present invention.

[0022] Figure 4 This is a schematic diagram of the normalized output of the voltage signal of the triboelectric nanogenerator in contact separation mode, based on the general analog circuit design of the present invention for signal acquisition and processing of low-frequency triboelectric nanogenerators.

[0023] Figure 5 This is a schematic diagram of the normalized output of the voltage signal of the triboelectric nanogenerator in sliding mode, based on the general analog circuit design of the present invention for signal acquisition and processing of low-frequency triboelectric nanogenerators.

[0024] Figure 6 This is a physical diagram of a signal acquisition and processing circuit for a triboelectric nanogenerator according to the present invention. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The step numbers in the following embodiments are only for ease of explanation and do not limit the order of the steps. The execution order of each step in the embodiments can be adapted according to the understanding of those skilled in the art.

[0026] Reference Figure 1 and Figure 6 The present invention provides a signal acquisition and processing circuit system for a triboelectric nanogenerator, comprising a potentiometer and voltage follower circuit, a second-order low-pass active filter circuit and a voltage comparison output circuit, wherein the potentiometer and voltage follower circuit, the second-order low-pass active filter circuit and the voltage comparison output circuit are connected in sequence.

[0027] Furthermore, this invention relates to a general analog circuit suitable for signal acquisition and processing of low-frequency triboelectric nanogenerators, comprising a modular interface and an internal signal processing unit, wherein the modular interface includes a set of input interfaces (included in...) Figure 1 Part 1, with ports named TENG+ and TENG-, is used to connect the two electrodes of the triboelectric nanogenerator; in single-electrode mode, only the TENG+ port needs to be connected. It also includes a set of power supply interfaces (included in...). Figure 6 ( Figure 1 (Not shown in the image) On the right side of the output pin group, one pin is connected to power (bottom), and one pin is connected to ground (top), used to power the entire system. There is also a set of output interfaces, including a high-level output interface (included in...). Figure 1 The middle part consists of three parts: a port named TTL_H_Out for outputting a high-level digital signal, and a low-level output interface (included in...). Figure 1 The middle part consists of three sections: a port named TTL_L_Out (used to output a low-level digital signal) and an analog output interface (included in...). Figure 1 The circuit consists of two parts, one of which is named Analog_Out (used to output analog signals). The internal signal processing unit is composed of an impedance matching unit, a voltage follower unit, a filtering unit, and a voltage comparator unit. The impedance matching unit consists of resistors and potentiometers to achieve impedance matching transformation between the circuit and the triboelectric nanogenerator to obtain a relatively suitable voltage value. The voltage follower unit and the filtering unit are both composed of integrated operational amplifiers, capacitors, and resistors to ensure the static stability of the circuit and obtain good waveform signals. The voltage comparator unit consists of voltage comparators and resistors to realize the output of digital signals.

[0028] The potentiometer and voltage follower circuit includes a DC bias circuit, a voltage follower circuit, and a voltage follower circuit.

[0029] The DC bias circuit is used to boost the quiescent operating point voltage from the ground plane reference voltage to half the supply voltage and adjust the input impedance of the entire circuit, thereby adjusting the voltage value when the triboelectric nanogenerator generates a signal. The voltage follower circuit is used to convert the high output impedance of the triboelectric nanogenerator to a low output impedance and boost the AC output quiescent point of the triboelectric nanogenerator to half the supply voltage. The voltage follower circuit achieves impedance conversion by obtaining a preset voltage with an input impedance greater than a preset threshold and outputting the signal with a low output impedance.

[0030] Specifically, the potentiometer and voltage follower circuit includes a DC bias circuit, a voltage follower circuit, and a voltage follower circuit comprising variable resistors R1, R2, and R3, capacitors C1 and C2, and a TLV272ID amplifier U1A. The variable resistors R1, R2, and R3 form the DC bias circuit; capacitors C1 and C2 form the voltage follower circuit; and the TLV272ID amplifier U1A forms the voltage follower circuit. The variable resistor R1 and the TLV272ID amplifier U1A perform impedance matching to normalize the triboelectric nanogenerator signal. In the potentiometer and voltage follower circuit, the sliding terminal of the variable resistor R1 is connected to the positive terminal of the triboelectric nanogenerator. The variable resistor R1 is connected to the positive terminal of the TLV272ID amplifier U1A. The second fixed terminal of the variable resistor R1 is connected to the second terminal of resistor R2, the first terminal of resistor R3, and the first terminal of capacitor C1. The second terminal of resistor R3, the second terminal of capacitor C1, and the negative terminal of the triboelectric nanogenerator are connected and grounded. The second pin of the TLV272ID amplifier U1A is connected to the second terminal of capacitor C2 and connected to a high level. The capacitor C2 and the first terminal of the TLV272ID amplifier U1A are grounded. The first terminal of resistor R2 is connected to a high level. The third pin and the negative terminal of the TLV272ID amplifier U1A are connected to a second-order low-pass active filter circuit.

[0031] Furthermore, the DC bias circuit consists of two large resistors R2 and R3 and a 2MΩ variable resistor potentiometer R1. Its function is to raise the static operating point voltage from the ground plane reference voltage to half the supply voltage to avoid negative half-cycle signal cutoff distortion when the AC signal enters the circuit. At the same time, the 2MΩ variable resistor potentiometer is connected in parallel in the circuit to adjust the input impedance of the entire circuit and achieve impedance matching. This allows adjustment of the voltage value obtained from the signal generated by the triboelectric nanogenerator. The connection method is that one end of the variable resistor R1 is connected to the reference voltage point, i.e., the connection point of the voltage divider resistors R2 and R3, and the other end is connected to the non-inverting input of the integrated operational amplifier. The voltage follower circuit consists of a rail-to-rail voltage output precision integrated operational amplifier of model TLV272ID. Its function is to obtain sufficient voltage through a large input impedance and output the signal through a low output impedance to complete the impedance conversion function. The connection method is that the non-inverting input of the integrated operational amplifier is connected to the signal input port of the triboelectric nanogenerator, and the inverting input is connected to its output.

[0032] The circuit's input impedance and reference voltage are changed by using a series and parallel connection of resistors and potentiometers. The series and parallel connection of resistors and potentiometers is achieved by using two 100kΩ axial-guided resistors to divide the voltage and increase the input reference voltage. A variable resistor with a total resistance of 2MΩ is connected between the two resistors, connecting the midpoint of the two resistors to the input interface of the triboelectric nanogenerator. A voltage follower is used as the pre-amplifier to ensure the static stability of the circuit. Its input port is a voltage follower composed of a general-purpose integrated operational amplifier of model TLV272ID as the pre-amplifier input.

[0033] The second-order low-pass active filter circuit is used to filter out high-frequency noise mixed in the output waveform of the triboelectric nanogenerator, so as to achieve a smoother and purer waveform output.

[0034] Specifically, the second-order low-pass active filter circuit includes resistors R4, R5, R6, and R7, capacitors C3 and C4, and a TLV272ID amplifier U1B. The first terminal of resistor R4 is connected to the third pin of the TLV272ID amplifier U1A in the potentiometer and voltage follower circuit. The first terminal of resistor R6 is connected to the negative terminal of the TLV272ID amplifier U1A in the potentiometer and voltage follower circuit. The second terminal of resistor R4 is connected to the first terminal of resistor R5 and the first terminal of capacitor C4. The second terminal of resistor R5 is connected to the first terminal of capacitor C3 and the positive terminal of the TLV272ID amplifier U1B. The second terminal of capacitor C3 is connected to the second terminal of resistor R6 and grounded. The second terminal of capacitor C4 is connected to the first terminal of resistor R7 and the negative terminal of the TLV272ID amplifier U1B. The third pin of the TLV272ID amplifier U1B is connected to the voltage comparison output circuit.

[0035] Furthermore, the second part of the Butterworth second-order low-pass active filter consists of two resistors R4 and R5, two capacitors C3 and C4, and an integrated operational amplifier of model TLV272ID. Its function is to filter out high-frequency noise (>10Hz) mixed in the output waveform of the triboelectric nanogenerator to achieve a smoother and purer waveform output. Its connection method is that the inverting input terminal of the integrated operational amplifier is connected to its output port, the non-inverting input terminal is connected in series with resistor R5 and feedback capacitor C4 and connected to the output port, one end of R4 is connected to the output port of the first part of the voltage follower section, and the other end is connected to the connection point of feedback capacitor and R5. One end of R6 is connected to the ground plane, and the other end is connected to the output port of the first part of the voltage follower section.

[0036] A low-pass active filter circuit is used as an intermediate-stage signal processing circuit. The low-pass active filter circuit is a Butterworth second-order low-pass active filter circuit with an upper cutoff frequency of approximately 10Hz.

[0037] The voltage comparison output circuit includes a first-stage hysteresis comparator circuit and a second-stage hysteresis comparator circuit. The first-stage hysteresis comparator circuit and the second-stage hysteresis comparator circuit are used to compare the output voltage of the comparator with the reference voltage value and output a stable high or low level. When the voltage rises or falls to a certain threshold, the current level is flipped and output. The first-stage hysteresis comparator circuit and the second-stage hysteresis comparator circuit correspond to two different threshold voltages.

[0038] Specifically, the first-stage hysteresis comparator circuit and the second-stage hysteresis comparator circuit include resistors R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, R19, R20, and R21; capacitors C5, C6, and C7; diode LED1; and LM393DR2G voltage comparator U2A and U2B. The resistors R8, R9, R12, R13, R17, R19, R21, C6, C7, and LM393DR2G voltage comparator U2A constitute the first stage. The hysteresis comparator circuit comprises resistors R10, R11, R14, R15, R16, R18, R20, diode LED1, capacitor C5, and LM393DR2G voltage comparator U2B, forming a second-stage hysteresis comparator circuit. In the voltage comparison output circuit, the first terminal of resistor R8 is connected to the third pin of TLV272ID amplifier U1B in the second-order low-pass active filter circuit. The second terminal of resistor R8 is connected to the first terminal of resistor R9, the positive terminal of LM393DR2G voltage comparator U2A, the positive terminal of LM393DR2G voltage comparator U2B, the first terminal of resistor R15, and the first terminal of resistor R14. The negative terminal of voltage comparator U2A is connected to the first terminal of capacitor C6. The second terminal of capacitor C6 is connected to the second terminal of resistor R13 and grounded. The second terminal of resistor R12 is connected to the first terminal of resistor R13, and the first terminal of resistor R12 is connected to a high level. The first pin of voltage comparator U2A is connected to the first terminal of resistor R17 and the first terminal of capacitor C7, respectively, and is connected to a high level. The second pin of voltage comparator U2A and the second terminal of capacitor C7 are grounded. The second terminal of resistor R15 is connected to the second terminal of resistor R17, the third pin of voltage comparator U2A, and the first terminal of resistor R19, respectively. The capacitor C... The second terminal of capacitor C5 is connected to the second terminal of resistor R11 and grounded. The first terminal of capacitor C5 is connected to the first terminal of resistor R11, the second terminal of resistor R10, and the negative terminal of LM393DR2G voltage comparator U2B. The first terminal of resistor R10 is connected to a high level. The second terminal of resistor R14 is connected to the second terminal of resistor R16, the first terminal of resistor R18, and the third pin of LM393DR2G voltage comparator U2B. The first terminal of resistor R16 is connected to a high level. The second terminal of resistor R18 is connected to the negative terminal of diode LED1 and outputs a low-level digital signal. The positive terminal of diode LED1 is connected to the second terminal of resistor R20. The first terminal of resistor R20 is connected to a high level.The second terminal of resistor R19 is connected to the first terminal of resistor R21 and outputs a high-level digital signal;

[0039] Furthermore, the voltage comparison output section of the third part consists of two hysteresis comparator circuits. The first hysteresis comparator circuit consists of a voltage comparator of model LM393DR2G and two voltage divider resistors R10 and R11. The second hysteresis comparator circuit also consists of a voltage comparator of model LM393DR2G and two voltage divider resistors R12 and R13. Its function is to generate a reference voltage value by dividing the voltage using voltage divider resistors R10, R11, R12, and R13. At the same time, the comparator circuit compares the output voltage of the filter circuit with the reference voltage value. After comparison, the output is stable at high and low levels. When the voltage rises or falls to a certain threshold, the output flips to show the current level. Each hysteresis comparator has two independent threshold voltages. The connection method is that the non-inverting input of the core part of the two voltage comparators is connected to the output port of the second-order low-pass active filter. The non-inverting input is connected to one end of the feedback resistors R14 and R15 respectively, and the output port is connected to the other end of the feedback resistors R14 and R15. The inverting input is connected to the reference voltage value point, i.e., the connection point of R10 and R11, R12 and R13.

[0040] Two sets of comparator circuits are used as the output digital signal of the subsequent signal processing circuit. There are three output interfaces in total, with the filter circuit and the two sets of comparator circuits connected to the output. The circuit can operate at a low power consumption of 3.3V or 5V during normal operation. The two sets of voltage comparison circuits are hysteresis comparison circuits composed of LM393DR2G comparators, with threshold values ​​of approximately 1 / 3VCC and 2 / 3VCC, respectively. It also has a set of triboelectric nanogenerator input interfaces with one positive and one negative interface pin, a set of power supply interfaces with one power supply and one ground, and a set of signal output interfaces including a positive signal voltage digital output, a negative signal voltage digital output, and an analog output interface. The general-purpose integrated operational amplifier TLV272ID and the comparator LM393DR2G selected in the circuit have the characteristics of low power consumption operation below 5V power supply and rail-rail output.

[0041] In summary, the specific working process of the circuit of the present invention is as follows:

[0042] S1. Based on the general-purpose integrated operational amplifier TLV272ID with high input impedance and low output impedance, impedance conversion is performed, and an adjustable potentiometer is used to adjust the input impedance. The input reference voltage is increased to 1 / 2VCC by using series and parallel resistors.

[0043] S2. Based on the general-purpose integrated operational amplifier TLV272ID, a Butterworth second-order low-pass active filter is designed using capacitors and resistors to filter the high-frequency noise of the output voltage signal generated in step S1. The cutoff frequency is about 10Hz, and the signal is output to the analog output port.

[0044] S3. Using a voltage comparator of model LM393DR2G combined with a resistor divider, design two sets of in-phase hysteresis comparators to perform high voltage comparison and low voltage comparison on the analog signal output in step S2, respectively. When a high voltage is generated, the voltage at the high voltage digital output port will generate a digital signal that jumps from 0V to VCC; when a low voltage is generated, the voltage at the low voltage digital output port will generate a digital signal that jumps from VCC to 0V.

[0045] S4. Design the schematic diagram and PCB package of the circuit, and then solder it to form the physical circuit.

[0046] Using the above method, the input voltage range of a general-purpose analog circuit suitable for signal acquisition and processing of low-frequency triboelectric nanogenerators is approximately 23V to 1.6×10⁻⁶. 4 The general analog circuit for signal acquisition and processing of low-frequency triboelectric nanogenerators described in this invention, with an operating voltage of 2V to 16V, an output voltage range of 4.66V under a 5V power supply, an output linearity of 2.79%, a circuit response time of approximately 10.2ms, an upper cutoff frequency of approximately 10Hz, lower voltage comparison thresholds of 2.10V and 2.46V, and upper voltage comparison thresholds of 2.96V and 2.60V, can be applied in signal acquisition of low-power triboelectric nanogenerators.

[0047] For the present invention Figure 2 This is a static reference voltage simulation diagram of the universal analog circuit design for signal acquisition and processing of low-frequency triboelectric nanogenerators, applicable to the present invention. Under the condition of no triboelectric nanogenerator signal input, the horizontal axis is... Figure 1 The first part shows the change in the variable resistor R1, and the vertical axis represents the voltage value of each output port of the circuit. The smaller the change in the output voltage value of the three output ports with the change of resistor R1, the more stable the circuit is.

[0048] For the present invention Figure 3 This is a simulation diagram of the open-circuit voltage and regularized signal of the triboelectric nanogenerator applied to the signal acquisition of the low-frequency triboelectric nanogenerator. The horizontal axis represents time, the left vertical axis represents the open-circuit output voltage value of the triboelectric nanogenerator, and the right vertical axis represents the output voltage value of the signal acquisition and processing circuit. The two comparative waveforms show that the high voltage open-circuit output of the triboelectric nanogenerator is transformed into a low voltage waveform of AC pulse after being processed by the signal acquisition and processing circuit.

[0049] For the present invention Figure 4 This is a schematic diagram illustrating the normalized output of the voltage signal from a triboelectric nanogenerator in contact-separation mode, based on the general analog circuit design for signal acquisition and processing of low-frequency triboelectric nanogenerators according to this invention. The horizontal axis represents time, and the vertical axis represents voltage magnitude. From top to bottom, it is divided into four parts: the open-circuit output of the contact-separation triboelectric nanogenerator (using polytetrafluoroethylene (PTFE) film as the negative dielectric layer, silver (Ag) as the electrode, and copper (Cu) as the positive dielectric layer material and electrode, constructing a contact-separation triboelectric nanogenerator that can represent both vertical contact-separation mode and single-electrode mode), the analog port output of the signal acquisition circuit, the low-level digital signal output, and the high-level digital signal output. The open-circuit voltage output amplitude of the triboelectric nanogenerator is approximately 120V, which, after processing by the signal acquisition and processing circuit, is converted into a low voltage with an analog output amplitude of approximately 3V and a digital output amplitude of approximately 5V.

[0050] For the present invention Figure 5 This is a schematic diagram illustrating the normalized output of the voltage signal from a triboelectric nanogenerator in sliding mode, based on the general analog circuit design for signal acquisition and processing of low-frequency triboelectric nanogenerators according to this invention. The horizontal axis represents time, and the vertical axis represents voltage magnitude. From top to bottom, it is divided into four parts: the open-circuit output of the sliding triboelectric nanogenerator (using a polytetrafluoroethylene (PTFE) film as the negative dielectric layer, silver (Ag) as the electrode, and copper (Cu) as the positive dielectric layer material and electrode to construct a sliding triboelectric nanogenerator that can represent the independent layer mode of horizontal sliding), the analog port output of the signal acquisition circuit, the low-level digital signal output, and the high-level digital signal output. The open-circuit voltage output amplitude of the triboelectric nanogenerator is approximately 200V, which, after processing by the signal acquisition and processing circuit, is converted into a low voltage with an analog output amplitude of approximately 4V and a digital output amplitude of approximately 5V.

[0051] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A signal acquisition and processing circuit system for a triboelectric nanogenerator, characterized in that, It includes a potentiometer and voltage follower circuit, a second-order low-pass active filter circuit, and a voltage comparison output circuit, wherein the potentiometer and voltage follower circuit, the second-order low-pass active filter circuit, and the voltage comparison output circuit are connected in sequence: The potentiometer and voltage follower circuit includes a DC bias circuit, a voltage follower circuit, and a voltage follower circuit. The DC bias circuit is used to raise the static operating point voltage from the ground plane reference voltage value to half the supply voltage value and adjust the input impedance of the entire circuit, thereby adjusting the voltage value when the triboelectric nanogenerator generates a signal. The voltage follower circuit is used to convert the high output impedance of the triboelectric nanogenerator to a low output impedance and to raise the AC output quiescent point of the triboelectric nanogenerator to half the power supply voltage value. The voltage follower circuit achieves impedance conversion by obtaining a preset voltage with an input impedance greater than a preset threshold and outputting a signal with a low output impedance. The second-order low-pass active filter circuit is used to filter out high-frequency noise mixed in the output waveform of the triboelectric nanogenerator, so as to achieve a smoother and purer waveform output. The voltage comparison output circuit includes a first-stage hysteresis comparator circuit and a second-stage hysteresis comparator circuit. The first-stage hysteresis comparator circuit and the second-stage hysteresis comparator circuit are used to compare the output voltage of the comparator to the reference voltage value and output a stable high or low level. When the voltage rises or falls to a certain threshold, the output level is flipped and the current level is output. The first-stage hysteresis comparator circuit and the second-stage hysteresis comparator circuit correspond to two different threshold voltages.

2. The signal acquisition and processing circuit system for a triboelectric nanogenerator according to claim 1, characterized in that, The potentiometer and voltage follower circuit includes a DC bias circuit, a voltage follower circuit, and a voltage follower circuit including variable resistors R1, R2, and R3, capacitors C1 and C2, and a TLV272ID amplifier U1A. The variable resistors R1, R2, and R3 form the DC bias circuit, the capacitors C1 and C2 form the voltage follower circuit, and the TLV272ID amplifier U1A forms the voltage follower circuit.

3. The signal acquisition and processing circuit system for a triboelectric nanogenerator according to claim 2, characterized in that, The variable resistor R1 and the TLV272ID amplifier U1A are impedance matched to normalize the triboelectric nanogenerator signal.

4. The signal acquisition and processing circuit system for a triboelectric nanogenerator according to claim 3, characterized in that, In the potentiometer and voltage follower circuit, the sliding terminal of the variable resistor R1 is connected to the positive terminal of the triboelectric nanogenerator, the first fixed terminal of the variable resistor R1 is connected to the positive terminal of the TLV272ID amplifier U1A, the second fixed terminal of the variable resistor R1 is connected to the second terminal of resistor R2, the first terminal of resistor R3, and the first terminal of capacitor C1, respectively, the second terminal of resistor R3, the second terminal of capacitor C1, and the negative terminal of the triboelectric nanogenerator are connected and grounded, the second pin of the TLV272ID amplifier U1A is connected to the second terminal of capacitor C2 and connected to a high level, the capacitor C2 and the first terminal of the TLV272ID amplifier U1A are grounded, the first terminal of resistor R2 is connected to a high level, and the third pin and the negative terminal of the TLV272ID amplifier U1A are connected to a second-order low-pass active filter circuit.

5. The signal acquisition and processing circuit system for a triboelectric nanogenerator according to claim 1, characterized in that, The second-order low-pass active filter circuit includes resistors R4, R5, R6, and R7, capacitors C3 and C4, and a TLV272ID amplifier U1B. The first terminal of resistor R4 is connected to the third pin of the TLV272ID amplifier U1A in the potentiometer and voltage follower circuit. The first terminal of resistor R6 is connected to the negative terminal of the TLV272ID amplifier U1A in the potentiometer and voltage follower circuit. The second terminal of resistor R4 is connected to the first terminal of resistor R5 and the first terminal of capacitor C4. The second terminal of resistor R5 is connected to the first terminal of capacitor C3 and the positive terminal of the TLV272ID amplifier U1B. The second terminal of capacitor C3 is connected to the second terminal of resistor R6 and grounded. The second terminal of capacitor C4 is connected to the first terminal of resistor R7 and the negative terminal of the TLV272ID amplifier U1B. The third pin of the TLV272ID amplifier U1B is connected to the voltage comparison output circuit.

6. The signal acquisition and processing circuit system for a triboelectric nanogenerator according to claim 1, characterized in that, The first-stage hysteresis comparator circuit and the second-stage hysteresis comparator circuit include resistors R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, R19, R20, and R21; capacitors C5, C6, and C7; diode LED1; and LM393DR2G voltage comparator U2A and U2B. The resistors R8, R9, R12, R13, R17, R19, R21, capacitors C6 and C7, and the LM393DR2G voltage comparator U2A form the first-stage hysteresis comparator circuit. The resistors R10, R11, R14, R15, R16, R18, R20, diode LED1, capacitor C5, and the LM393DR2G voltage comparator U2B form the second-stage hysteresis comparator circuit.

7. The signal acquisition and processing circuit system for a triboelectric nanogenerator according to claim 6, characterized in that, In the voltage comparison output circuit, the first end of resistor R8 is connected to the third pin of the TLV272ID amplifier U1B in the second-order low-pass active filter circuit. The second end of resistor R8 is connected to the first end of resistor R9, the positive terminal of LM393DR2G voltage comparator U2A, the positive terminal of LM393DR2G voltage comparator U2B, the first end of resistor R15, and the first end of resistor R14. The negative terminal of LM393DR2G voltage comparator U2A is connected to the first end of capacitor C6. The second end of capacitor C6 is connected to the second end of resistor R13 and grounded. The second end of resistor R12 is connected to the first end of resistor R13, and the first end of resistor R12 is connected to a high level. The first pin of LM393DR2G voltage comparator U2A is connected to the first end of resistor R17 and the first end of capacitor C7 and connected to a high level. The second pin of LM393DR2G voltage comparator U2A and the second end of capacitor C7 are grounded. The second terminal of capacitor C5 is connected to the second terminal of resistor R17, the third pin of LM393DR2G voltage comparator U2A, and the first terminal of resistor R19. The second terminal of capacitor C5 is connected to the second terminal of resistor R11 and grounded. The first terminal of capacitor C5 is connected to the first terminal of resistor R11, the second terminal of resistor R10, and the negative terminal of LM393DR2G voltage comparator U2B. The first terminal of resistor R10 is connected to a high level. The second terminal of resistor R14 is connected to the second terminal of resistor R16, the first terminal of resistor R18, and the third pin of LM393DR2G voltage comparator U2B. The first terminal of resistor R16 is connected to a high level. The second terminal of resistor R18 is connected to the negative terminal of diode LED1 and outputs a low-level digital signal. The positive terminal of diode LED1 is connected to the second terminal of resistor R20. The first terminal of resistor R20 is connected to a high level. The second terminal of resistor R19 is connected to the first terminal of resistor R21 and outputs a high-level digital signal.

Images