Electrostatic detection circuit and system

Abstract

The utility model discloses a static electricity detection circuit and system, and relates to the static electricity detection field, the static electricity detection circuit is provided with an induction device, a signal amplification circuit, a band-pass filter circuit, a signal shaping circuit, and a signal processing circuit; the sensing device can sense a plurality of initial pulse signals generated in the ATN electrostatic discharge process, the signal amplifying circuit can convert the initial pulse signals into positive pulse signals with the amplitude being a preset first amplitude, and the band-pass filtering circuit and the signal shaping circuit sequentially filter and combine the positive pulse signals. And when the signal processing circuit receives the combined total pulse signal, the combined total pulse signal is converted into a square wave of which the amplitude is a preset second amplitude, so that the MCU can detect the electrostatic discharge condition of the ATN in time. The electrostatic discharge detection can be realized only by connecting to one interface of the MCU, so that the electrostatic detection circuit provided by the scheme has the advantages that the resource requirement of the MCU is reduced, and the cost is reduced.

Description

Technical Field

[0001] The utility model relates to the field of static electricity detection, in particular to a static electricity detection circuit and system. Background Art

[0002] As we all know, electrostatic discharge can generate high voltage, strong electric field and instantaneous large current, which can interfere with the internal hardware circuit of the meter and even burn it out. Electricity thieves will use electrostatic discharge to affect the ATN (a PCB (Printed Circuit Board) loop antenna) and other devices in the meter to steal electricity. Therefore, there is an urgent need for a circuit to detect the electrostatic discharge of ATN and other devices. Utility Model Content

[0003] The purpose of the utility model is to provide an electrostatic detection circuit and system. When the ATN is in an electrostatic discharge state, the induction device will sense several initial pulse signals generated during the electrostatic discharge process of the ATN, and the MCU will receive a square wave of a preset amplitude, so that the MCU can detect the electrostatic discharge of the ATN in time. Because this solution only needs to be connected to an interface of the MCU to realize electrostatic discharge detection, the electrostatic detection circuit provided by this solution reduces the resource requirements of the MCU and reduces the cost.

[0004] In order to solve the above technical problems, the utility model provides a static electricity detection circuit, including: an induction device, a signal amplification circuit, a bandpass filter circuit, a signal shaping circuit, and a signal processing circuit;

[0005] The two ends of the induction device are connected to the ATN, and are used to sense a number of initial pulse signals generated by the ATN during the electrostatic discharge process;

[0006] The positive phase input terminal and the negative phase input terminal of the signal amplifying circuit are connected in parallel with the inductive device, and the negative phase input terminal is connected with the output terminal of the signal amplifying circuit, so as to convert each of the initial pulse signals into a plurality of positive pulse signals with an amplitude of a preset first amplitude;

[0007] The input end of the bandpass filter circuit is connected to the output end of the signal amplification circuit, and is used to filter each of the positive pulse signals;

[0008] The input end of the signal shaping circuit is connected to the output end of the bandpass filtering circuit, and is used to combine the positive pulse signals after filtering into a total pulse signal;

[0009] The input end of the signal processing circuit is connected to the output end of the signal shaping circuit, and the output end is connected to the GPIO port of the MCU, for converting the total pulse signal into a square wave with an amplitude of a preset second amplitude, and transmitting the square wave to the GPIO port of the MCU, so that the MCU determines that the ATN is in an electrostatic discharge state when receiving the square wave.

[0010] Optionally, the sensing device is a first capacitor, and both ends of the first capacitor are connected to the ATN for sensing each of the initial pulse signals generated by the ATN during electrostatic discharge.

[0011] Optionally, the signal amplifying circuit includes: an anti-reverse connection module, a first resistor, a second resistor, an amplifier, and a third resistor;

[0012] The anti-reverse connection module is connected in parallel with the inductive device, and is used for conducting when the voltage at the first terminal of the inductive device is less than the voltage at the second terminal of the inductive device;

[0013] The first end of the first resistor is connected to the first end of the inductive device, and the second end is connected to the non-inverting input end of the amplifier;

[0014] The first end of the second resistor is connected to the first end of the second capacitor, and the second end is respectively connected to the negative phase input end of the amplifier and the first end of the third resistor;

[0015] The output end of the amplifier is connected to the input end of the bandpass filter circuit, the power supply end is connected to the power supply, and the ground end is connected to the ground, and is used to differentially amplify the first terminal voltage of the induction device and the second terminal voltage of the induction device, and convert each of the initial pulse signals into each of the positive pulse signals;

[0016] The second end of the third resistor is connected to the output end of the amplifier.

[0017] Optionally, the anti-reverse connection module is a first diode, an anode of the first diode is connected to a first end of the sensing device, and a cathode of the first diode is connected to a second end of the sensing device.

[0018] Optionally, the bandpass filter circuit includes: a fourth resistor, a second capacitor, a third capacitor, and a fifth resistor;

[0019] The fourth resistor is connected in parallel with the input end of the signal shaping circuit;

[0020] The first end of the second capacitor is connected to the first end of the fourth resistor, and the second end is connected to the first end of the fifth resistor and the first end of the third capacitor respectively;

[0021] The second end of the third capacitor is connected to the second end of the fourth resistor and the ground line;

[0022] The second end of the fifth resistor is connected to the output end of the signal amplifying circuit.

[0023] Optionally, the signal shaping circuit comprises: a second diode, a fourth capacitor, and a third diode;

[0024] The anode of the second diode is connected to the first end of the fourth resistor, and the cathode is connected to the first end of the fourth capacitor;

[0025] The second end of the fourth capacitor is connected to the second end of the fourth resistor;

[0026] The third diode is connected in parallel with the fourth capacitor and the signal processing circuit respectively, the anode of the third diode is connected to the second end of the fourth capacitor, and the cathode is connected to the first end of the fourth capacitor and the cathode of the second diode respectively.

[0027] Optionally, the signal processing circuit includes: a sixth resistor, a seventh resistor, and an NPN transistor;

[0028] The first end of the sixth resistor is connected to the cathode of the third diode, and the second end is connected to the base of the NPN transistor;

[0029] The collector of the NPN transistor is respectively connected to the first end of the seventh resistor and the GPIO port of the MCU, and the emitter is connected to the anode of the third diode, and is used to turn on when receiving the total pulse signal, and convert the total pulse signal into the square wave, and transmit the square wave to the GPIO port of the MCU;

[0030] The second end of the seventh resistor is connected to a power source.

[0031] Optionally, also include:

[0032] A protection circuit, wherein the input end of the protection circuit is connected in parallel with the inductive device, and the output end is connected in parallel with the positive phase input end and the negative phase input end of the signal amplifying circuit, and is used to limit the voltage in the loop.

[0033] Optionally, the protection circuit includes: an eighth resistor, a ninth resistor, a fifth capacitor, and a sixth capacitor;

[0034] The first end of the eighth resistor is connected to the first end of the inductive device, and the second end is connected to the first end of the fifth capacitor and the first end of the sixth capacitor respectively;

[0035] The first end of the ninth resistor is connected to the second end of the inductive device and the second end of the fifth capacitor respectively, and the second end is connected to the ground;

[0036] The second end of the fifth capacitor is connected to the negative phase input end of the signal amplifying circuit;

[0037] The second end of the sixth capacitor is connected to the non-inverting input end of the signal amplifying circuit.

[0038] In order to solve the above technical problems, the utility model further provides an electrostatic detection system, comprising: an MCU and the electrostatic detection circuit as described above, wherein the electrostatic detection circuit is connected to the MCU.

[0039] The purpose of the utility model is to provide an electrostatic detection circuit and system, in which an induction device, a signal amplification circuit, a bandpass filter circuit, a signal shaping circuit, and a signal processing circuit are provided in the electrostatic detection circuit. When the ATN is in an electrostatic discharge state, the induction device will sense a number of initial pulse signals generated during the electrostatic discharge process of the ATN, and the signal amplification circuit will convert them into positive pulse signals with an amplitude of a preset first amplitude. The bandpass filter circuit and the signal shaping circuit filter and merge each positive pulse signal in turn, so that when the signal processing circuit receives the total pulse signal after the merger, it converts it into a square wave with an amplitude of a preset second amplitude, so that the MCU can detect the electrostatic discharge of the ATN in time. Because this solution only needs to be connected to an interface of the MCU to realize electrostatic discharge detection, the electrostatic detection circuit provided by this solution reduces the resource requirements of the MCU and reduces the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0041] Figure 1 A schematic diagram of the structure of an electrostatic detection circuit provided by the utility model;

[0042] Figure 2 This is a structural schematic diagram of another electrostatic detection circuit provided by the utility model. DETAILED DESCRIPTION

[0043] The core of the utility model is to provide an electrostatic detection circuit and system. When the ATN is in an electrostatic discharge state, the induction device will sense several initial pulse signals generated during the electrostatic discharge process of the ATN, and the MCU will receive a square wave of a preset amplitude, so that the MCU can detect the electrostatic discharge of the ATN in time. Because this solution only needs to be connected to an interface of the MCU to realize electrostatic discharge detection, the electrostatic detection circuit provided by this solution reduces the resource requirements of the MCU and reduces the cost.

[0044] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0045] Please refer to Figure 1 , Figure 1 The schematic diagram of the structure of a static electricity detection circuit provided by the utility model. The static electricity detection circuit includes: an induction device 1, a signal amplification circuit 2, a bandpass filter circuit 3, a signal shaping circuit 4, and a signal processing circuit 5;

[0046] Two ends of the sensing device 1 are connected to the ATN to sense a number of initial pulse signals generated by the ATN during electrostatic discharge;

[0047] The positive phase input terminal and the negative phase input terminal of the signal amplifying circuit 2 are connected in parallel with the inductive device 1, and the negative phase input terminal is connected with the output terminal of the signal amplifying circuit 2, so as to convert each initial pulse signal into a plurality of positive pulse signals with an amplitude of a preset first amplitude;

[0048] The input end of the bandpass filter circuit 3 is connected to the output end of the signal amplification circuit 2, and is used to filter each positive pulse signal;

[0049] The input end of the signal shaping circuit 4 is connected to the output end of the bandpass filtering circuit 3, and is used to combine the filtered positive pulse signals into a total pulse signal;

[0050] The input end of the signal processing circuit 5 is connected to the output end of the signal shaping circuit 4, and the output end is connected to the GPIO port of the MCU, so as to convert the total pulse signal into a square wave with an amplitude of a preset second amplitude, and transmit the square wave to the GPIO port of the MCU, so that the MCU determines that the ATN is in an electrostatic discharge state when receiving the square wave.

[0051] In the utility model, the electrostatic detection circuit is provided with an induction device 1, a signal amplification circuit 2, a bandpass filtering circuit 3, a signal shaping circuit 4, and a signal processing circuit 5. When the ATN is in an electrostatic discharge state, the ATN will convert the high-frequency electromagnetic wave signal generated in the electrostatic discharge process into a voltage signal, and the induction device 1 will sense the corresponding pulse signal, that is, the initial pulse signal, and the signal amplification circuit 2 will convert the several initial pulse signals sensed by the induction device 1 into positive pulse signals with an amplitude of a preset first amplitude, and the bandpass filtering circuit 3 will filter each positive pulse signal to filter out the interference signal in each positive pulse signal, and the signal shaping circuit 4 will merge the filtered positive pulse signals into a total pulse signal, and the signal processing circuit 5 will convert the total pulse signal into a square wave with an amplitude of a preset second amplitude, and transmit it to the GPIO (General-Purpose I / O) of the MCU (Microcontroller Unit). Input / OutputPorts, general-purpose input / output ports) ports are convenient for MCU processing, thereby detecting the electrostatic discharge of the ATN more quickly and facilitating subsequent maintenance. In addition, the electrostatic detection circuit only needs to be connected to an interface of the MCU to realize electrostatic discharge detection, so the electrostatic detection circuit provided by this solution reduces the resource requirements of the MCU, and a cheaper MCU can be selected, reducing costs.

[0052] It should be noted that, in practical applications, ATN is a PCB loop antenna with about 20 turns. ATN can convert the high-frequency electromagnetic wave signal generated during electrostatic discharge into a voltage signal. (When ATN is a positive voltage electrostatic discharge, a negative pulse signal will be sensed at both ends of the inductive device 1; when ATN is a negative voltage electrostatic discharge, a positive pulse signal will be sensed at both ends of the inductive device 1). In practical applications, the inductive device 1 can be a capacitor or other inductive devices.

[0053] It should also be noted that the present application does not make any special limitation on the preset first amplitude and the preset second amplitude, and the actual values ​​of the preset first amplitude and the preset second amplitude are determined by actual needs and specific circuit structures.

[0054] This embodiment provides an electrostatic detection circuit, in which an induction device 1, a signal amplification circuit 2, a bandpass filter circuit 3, a signal shaping circuit 4, and a signal processing circuit 5 are provided. When the ATN is in an electrostatic discharge state, the induction device 1 will sense several initial pulse signals generated during the electrostatic discharge process of the ATN, and the signal amplification circuit 2 will convert them into positive pulse signals with an amplitude of a preset first amplitude. The bandpass filter circuit 3 and the signal shaping circuit 4 filter and merge each positive pulse signal in turn, so that the signal processing circuit 5 converts the total pulse signal after the merger into a square wave with an amplitude of a preset second amplitude when receiving it, so that the MCU can detect the electrostatic discharge of the ATN in time. Because this solution only needs to be connected to an interface of the MCU to realize electrostatic discharge detection, the electrostatic detection circuit provided by this solution reduces the resource requirements of the MCU and reduces the cost.

[0055] Based on the above embodiments:

[0056] As an optional embodiment, the sensing device 1 is a first capacitor C1 , and both ends of the first capacitor C1 are connected to the ATN for sensing each initial pulse signal generated by the ATN during the electrostatic discharge process.

[0057] In the present invention, the inductive device 1 is a first capacitor C1. Since the capacitor has the advantages of extremely low loss, low dielectric absorption coefficient, high insulation, good frequency characteristics, excellent self-healing property, and high stability, the present solution adopts the first capacitor C1 as the inductive device 1.

[0058] As an optional embodiment, the signal amplifying circuit 2 includes: an anti-reverse connection module, a first resistor R1, a second resistor R2, an amplifier, and a third resistor R3;

[0059] The reverse connection prevention module is connected in parallel with the inductive device 1 and is used for conducting when the voltage at the first terminal of the inductive device 1 is less than the voltage at the second terminal of the inductive device 1;

[0060] A first end of the first resistor R1 is connected to a first end of the inductive device 1, and a second end is connected to a non-inverting input end of the amplifier;

[0061] A first end of the second resistor R2 is connected to a first end of the second capacitor C2, and a second end is connected to a negative phase input end of the amplifier and a first end of the third resistor R3 respectively;

[0062] The output end of the amplifier is connected to the input end of the bandpass filter circuit 3, the power supply end is connected to the power supply, and the ground end is connected to the ground, and is used to differentially amplify the first terminal voltage of the induction device 1 and the second terminal voltage of the induction device 1, and convert each initial pulse signal into each positive pulse signal;

[0063] The second end of the third resistor R3 is connected to the output end of the amplifier.

[0064] In the utility model, the signal amplification circuit 2 is provided with an anti-reverse connection module, a first resistor R1, a second resistor R2, an amplifier, and a third resistor R3. When the voltage at the first terminal of the sensing device 1 is greater than the voltage at the second terminal of the sensing device 1, the anti-reverse connection module is turned off, and the amplifier works normally. The amplifier can differentially amplify the voltage at the first terminal of the sensing device 1 and the voltage at the second terminal of the sensing device 1, and convert each initial pulse signal into each positive pulse signal. The amplitude of the positive pulse signal output by the amplifier is related to the resistance values ​​of the first resistor R1, the second resistor R2 and the third resistor R3, so the amplitudes of each positive pulse signal are equal and are all preset first amplitudes. The number of components is small, and the volume and cost are reduced.

[0065] As an optional embodiment, the reverse connection prevention module is a first diode D1 , an anode of the first diode D1 is connected to the first end of the sensing device 1 , and a cathode of the first diode D1 is connected to the second end of the sensing device 1 .

[0066] In the utility model, the diode is used as the anti-reverse connection module because the diode has the advantages of low driving voltage, small working current, strong anti-vibration and impact ability, small size, high reliability, low power consumption and long life.

[0067] As an optional embodiment, the bandpass filter circuit 3 includes: a fourth resistor R4, a second capacitor C2, a third capacitor C3, and a fifth resistor R5;

[0068] The fourth resistor R4 is connected in parallel with the input end of the signal shaping circuit 4;

[0069] The first end of the second capacitor C2 is connected to the first end of the fourth resistor R4, and the second end is connected to the first end of the fifth resistor R5 and the first end of the third capacitor C3 respectively;

[0070] The second end of the third capacitor C3 is connected to the second end of the fourth resistor R4 and the ground line;

[0071] A second end of the fifth resistor R5 is connected to the output end of the signal amplifying circuit 2 .

[0072] In the utility model, a fourth resistor R4, a second capacitor C2, a third capacitor C3, and a fifth resistor R5 are provided in the bandpass filter circuit 3, wherein the fifth resistor R5 is provided at the output end of the signal amplifying circuit 2, and plays a role of voltage limiting, thereby improving the safety of the electrostatic detection circuit, and the second capacitor C2, the third capacitor C3, and the fourth resistor R4 constitute an RC filter circuit with fewer components, so it has the advantage of low cost and is convenient for practical application.

[0073] As an optional embodiment, the signal shaping circuit 4 includes: a second diode D2, a fourth capacitor C4, and a third diode D3;

[0074] The anode of the second diode D2 is connected to the first end of the fourth resistor R4, and the cathode is connected to the first end of the fourth capacitor C4;

[0075] The second end of the fourth capacitor C4 is connected to the second end of the fourth resistor R4;

[0076] The third diode D3 is connected in parallel with the fourth capacitor C4 and the signal processing circuit 5 respectively. The anode of the third diode D3 is connected to the second end of the fourth capacitor C4, and the cathode is connected to the first end of the fourth capacitor C4 and the cathode of the second diode D2 respectively.

[0077] In the utility model, a second diode D2, a fourth capacitor C4, and a third diode D3 are provided in the signal shaping circuit 4, wherein the second diode D2 and the third diode D3 are provided to ensure that the fourth capacitor C4 can completely absorb the several positive pulse signals output by the signal amplifying circuit 2, so as to output a total pulse signal to the signal processing circuit 5, so as to facilitate the subsequent detection by the MCU.

[0078] It should be noted that, in practical applications, the signal shaping circuit 4 can measure several short-duration pulse signals sensed by the ATN during a single electrostatic discharge. This circuit combines several positive pulse signals into a total pulse signal, and as the capacitance of the fourth capacitor C4 increases, the width of the combined single total pulse signal gradually widens.

[0079] As an optional embodiment, the signal processing circuit 5 includes: a sixth resistor R6, a seventh resistor R7, and an NPN transistor Q1;

[0080] A first end of the sixth resistor R6 is connected to the cathode of the third diode D3, and a second end thereof is connected to the base of the NPN transistor Q1;

[0081] The collector of the NPN transistor Q1 is respectively connected to the first end of the seventh resistor R7 and the GPIO port of the MCU, and the emitter is connected to the anode of the third diode D3, and is used to turn on when receiving the total pulse signal, and convert the total pulse signal into a square wave, and transmit the square wave to the GPIO port of the MCU;

[0082] A second end of the seventh resistor R7 is connected to the power supply.

[0083] In the utility model, the signal processing circuit 5 is provided with a sixth resistor R6, a seventh resistor R7, and an NPN transistor Q1, wherein the sixth resistor R6 plays a role of voltage limiting. When the signal shaping circuit 4 outputs a total pulse signal, the NPN transistor Q1 will be turned on accordingly according to the total pulse signal, and under the action of the seventh resistor R7 and the power supply, it will be pulled up to convert the total pulse signal into a square wave, and the amplitude of the square wave is determined by the seventh resistor R7 and the power supply. The purpose of setting the transistor in the signal processing circuit 5 is to make the levels of the high and low signals transmitted to the GPIO port of the MCU more stable, and the signal processing circuit 5 provided by this scheme has a small number of components and a low cost.

[0084] It should be noted that, by applying the electrostatic detection circuit in this solution, in actual applications, the MCU only needs one GPIO interface to collect the square wave output by the signal processing circuit 5, and detects the high and low levels of the square wave to achieve electrostatic detection, which reduces the calculation difficulty and workload of the MCU, and reduces the requirements on the resources of the MCU, thereby achieving the purpose of reducing costs.

[0085] It should also be noted that in actual applications, when the MCU detects the square wave output by the signal processing circuit 5, it can determine whether the ATN is in a state of electrostatic discharge based on the square wave, thereby preventing theft of electricity through high-voltage static electricity and preventing the measurement of high-voltage static electricity. When the anti-theft mode is detected, it switches to the penalty metering mode to ensure the benefits of the power company. A serious warning is given to the electricity theft user.

[0086] As an optional embodiment, it also includes:

[0087] The protection circuit 6 has an input end connected in parallel with the induction device 1 and an output end connected in parallel with the positive phase input end and the negative phase input end of the signal amplifying circuit 2, and is used to limit the voltage in the loop.

[0088] In the utility model, a protection circuit 6 is also provided in the electrostatic detection circuit. The protection circuit 6 is arranged between the sensing device 1 and the signal amplifying circuit 2, and can limit the voltage in the loop to prevent the voltage of the initial pulse signal sensed by the sensing device 1 from being too high and damaging the back-end circuit, thereby improving the safety and reliability of the solution.

[0089] As an optional embodiment, the protection circuit 6 includes: an eighth resistor R8, a ninth resistor R9, a fifth capacitor C5, and a sixth capacitor C6;

[0090] A first end of the eighth resistor R8 is connected to the first end of the inductive device 1, and a second end thereof is connected to the first end of the fifth capacitor C5 and the first end of the sixth capacitor C6 respectively;

[0091] A first end of the ninth resistor R9 is connected to the second end of the inductive device 1 and the second end of the fifth capacitor C5 respectively, and a second end thereof is connected to the ground;

[0092] The second end of the fifth capacitor C5 is connected to the negative phase input end of the signal amplifying circuit 2;

[0093] The second end of the sixth capacitor C6 is connected to the non-inverting input end of the signal amplifying circuit 2 .

[0094] In the utility model, Figure 2 As shown, the protection circuit 6 is provided with an eighth resistor R8, a ninth resistor R9, a fifth capacitor C5, and a sixth capacitor C6, wherein the eighth resistor R8 and the ninth resistor R9 form a voltage divider circuit, which can limit the voltage in the loop, and the fifth capacitor C5 and the sixth capacitor C6 play a filtering role, and can filter out some interference signals in the initial pulse signal, which can prevent the voltage of the initial pulse signal from being too high and damaging the back-end circuit, and can also improve the accuracy of subsequent detection by filtering out the interference signal.

[0095] It should be noted that, in practical applications, the protection circuit 6 may also be provided with a fuse or other protection device to perform timely shutdown when the loop voltage is too high, so as to achieve the purpose of protecting the circuit 6 .

[0096] The utility model also provides an embodiment corresponding to a static electricity detection system, comprising: an MCU and the static electricity detection circuit as described above, wherein the static electricity detection circuit is connected to the MCU.

[0097] The electrostatic detection system provided in this embodiment corresponds to the above-mentioned electrostatic detection circuit, so it has the same beneficial effects as the above-mentioned electrostatic detection circuit. Therefore, for the embodiments of the electrostatic detection system part, please refer to the description of the embodiments of the electrostatic detection circuit part, which will not be repeated here.

[0098] It should be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0099] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An electrostatic detection circuit, characterized in that: include: Inductive devices, signal amplification circuits, bandpass filter circuits, signal shaping circuits, signal processing circuits; The two ends of the induction device are connected to the ATN, and are used to sense a number of initial pulse signals generated by the ATN during the electrostatic discharge process; The positive phase input terminal and the negative phase input terminal of the signal amplifying circuit are connected in parallel with the inductive device, and the negative phase input terminal is connected with the output terminal of the signal amplifying circuit, so as to convert each of the initial pulse signals into a plurality of positive pulse signals with an amplitude of a preset first amplitude; The input end of the bandpass filter circuit is connected to the output end of the signal amplification circuit, and is used to filter each of the positive pulse signals; The input end of the signal shaping circuit is connected to the output end of the bandpass filtering circuit, and is used to combine the positive pulse signals after filtering into a total pulse signal; The input end of the signal processing circuit is connected to the output end of the signal shaping circuit, and the output end is connected to the GPIO port of the MCU, for converting the total pulse signal into a square wave with an amplitude of a preset second amplitude, and transmitting the square wave to the GPIO port of the MCU, so that the MCU determines that the ATN is in an electrostatic discharge state when receiving the square wave.

2. The static electricity detection circuit according to claim 1, characterized in that: The sensing device is a first capacitor, both ends of which are connected to the ATN, and is used to sense the initial pulse signals generated by the ATN during electrostatic discharge.

3. The static electricity detection circuit according to claim 1, characterized in that: The signal amplifying circuit comprises: an anti-reverse connection module, a first resistor, a second resistor, an amplifier, and a third resistor; The anti-reverse connection module is connected in parallel with the inductive device, and is used for conducting when the voltage at the first terminal of the inductive device is less than the voltage at the second terminal of the inductive device; The first end of the first resistor is connected to the first end of the inductive device, and the second end is connected to the non-inverting input end of the amplifier; The first end of the second resistor is connected to the second end of the inductive device, and the second end is respectively connected to the negative phase input end of the amplifier and the first end of the third resistor; The output end of the amplifier is connected to the input end of the bandpass filter circuit, the power supply end is connected to the power supply, and the ground end is connected to the ground, and is used to differentially amplify the first terminal voltage of the induction device and the second terminal voltage of the induction device, and convert each of the initial pulse signals into each of the positive pulse signals; The second end of the third resistor is connected to the output end of the amplifier.

4. The static electricity detection circuit according to claim 3, characterized in that: The anti-reverse connection module is a first diode, an anode of the first diode is connected to a first end of the sensing device, and a cathode of the first diode is connected to a second end of the sensing device.

5. The static electricity detection circuit according to claim 1, wherein: The bandpass filter circuit comprises: a fourth resistor, a second capacitor, a third capacitor, and a fifth resistor; The fourth resistor is connected in parallel with the input end of the signal shaping circuit; The first end of the second capacitor is connected to the first end of the fourth resistor, and the second end is connected to the first end of the fifth resistor and the first end of the third capacitor respectively; The second end of the third capacitor is connected to the second end of the fourth resistor and the ground line; The second end of the fifth resistor is connected to the output end of the signal amplifying circuit.

6. The static electricity detection circuit according to claim 5, characterized in that: The signal shaping circuit comprises: a second diode, a fourth capacitor, and a third diode; The anode of the second diode is connected to the first end of the fourth resistor, and the cathode is connected to the first end of the fourth capacitor; The second end of the fourth capacitor is connected to the second end of the fourth resistor; The third diode is connected in parallel with the fourth capacitor and the signal processing circuit respectively, the anode of the third diode is connected to the second end of the fourth capacitor, and the cathode is connected to the first end of the fourth capacitor and the cathode of the second diode respectively.

7. The static electricity detection circuit according to claim 6, characterized in that: The signal processing circuit comprises: a sixth resistor, a seventh resistor, and an NPN transistor; The first end of the sixth resistor is connected to the cathode of the third diode, and the second end is connected to the base of the NPN transistor; The collector of the NPN transistor is respectively connected to the first end of the seventh resistor and the GPIO port of the MCU, and the emitter is connected to the anode of the third diode, and is used to turn on when receiving the total pulse signal, and convert the total pulse signal into the square wave, and transmit the square wave to the GPIO port of the MCU; The second end of the seventh resistor is connected to a power source.

8. The static electricity detection circuit according to any one of claims 1 to 7, characterized in that: Also includes: A protection circuit, wherein the input end of the protection circuit is connected in parallel with the inductive device, and the output end is connected in parallel with the positive phase input end and the negative phase input end of the signal amplifying circuit, and is used to limit the voltage in the loop.

9. The static electricity detection circuit according to claim 8, characterized in that: The protection circuit comprises: an eighth resistor, a ninth resistor, a fifth capacitor, and a sixth capacitor; The first end of the eighth resistor is connected to the first end of the inductive device, and the second end is connected to the first end of the fifth capacitor and the first end of the sixth capacitor respectively; The first end of the ninth resistor is connected to the second end of the inductive device and the second end of the fifth capacitor respectively, and the second end is connected to the ground; The second end of the fifth capacitor is connected to the negative phase input end of the signal amplifying circuit; The second end of the sixth capacitor is connected to the non-inverting input end of the signal amplifying circuit.

10. An electrostatic detection system, characterized in that: include: An MCU and an electrostatic detection circuit as described in any one of claims 1 to 9, wherein the electrostatic detection circuit is connected to the MCU.

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