Anti-interference power supply input port circuit

Abstract

The invention provides an anti-interference power supply input port circuit, which comprises an anti-transient impact circuit, a common-mode filter circuit and a differential-mode filter circuit, wherein the anti-transient impact circuit is used for eliminating transient voltage impact caused by various reasons; the transient voltage surge refers to sudden change of circuit voltage; the common-mode filter circuit is used for filtering common-mode interference on the circuit; and the differential mode filter circuit is used for filtering differential mode interference on the circuit. According to the embodiment of the invention, through the coordination effect of the common-mode filter circuit and the differential-mode filter circuit, the interference of different modes can be effectively filtered out, and the anti-interference capability of the circuit is improved; through the coordination effect of the transient impact prevention circuit, the common-mode filter circuit and the differential-mode filter circuit, comprehensive protection of a power supply input port can be realized, transient voltage impact can be dealt with, and electromagnetic interference can also be inhibited; the reliability of the whole power supply input port circuit is improved, so that the power supply input port circuit can stably work in a severe power supply environment and an electromagnetic interference environment.

Description

Technical Field

[0001] This invention relates to the field of electronic technology, and more specifically to an anti-interference power input port circuit. Background Art

[0002] With the rapid development of the automotive industry, the level of automotive electronics and intelligence is constantly improving, leading to a dramatic increase in the number of electronic devices in vehicles. These devices include, but are not limited to, in-vehicle infotainment systems, advanced driver assistance systems (ADAS), electric power steering systems (EPS), and anti-lock braking systems (ABS). As the number of automotive electronic devices increases, the input voltages also become more diverse, making electromagnetic interference between systems increasingly prominent. This interference may originate from the switching operations of motors, the transmission of wireless communication devices, and the high-frequency switching actions of power conversion equipment. Electromagnetic interference not only affects the normal operation of electronic devices but may also pose a threat to the safety of drivers and passengers.

[0003] Therefore, there is an urgent need for a power input port circuit that can effectively suppress and filter various electromagnetic interferences. Summary of the Invention

[0004] In view of this, the present invention provides an anti-interference power input port circuit to solve the problem that the diversity of electromagnetic interference caused by the diversity of input voltage can easily lead to equipment failure and affect passenger safety.

[0005] In a first aspect, the present invention provides an anti-interference power input port circuit, the power input port circuit including a transient surge protection circuit, a common-mode filter circuit, and a differential-mode filter circuit:

[0006] The transient voltage surge protection circuit is used to eliminate transient voltage surges caused by various reasons; the transient voltage surge refers to a sudden change in circuit voltage.

[0007] The common-mode filter circuit is used to filter common-mode interference on the circuit.

[0008] The differential mode filter circuit is used to filter differential mode interference on the circuit.

[0009] This application embodiment effectively filters out interference of different modes by coordinating the common-mode filter circuit and the differential-mode filter circuit, thereby improving the circuit's anti-interference capability. Through the coordinated action of the transient surge protection circuit, the common-mode filter circuit, and the differential-mode filter circuit, comprehensive protection of the power input port can be achieved. It can not only cope with transient voltage surges but also suppress electromagnetic interference, providing more comprehensive protection. This improves the reliability of the entire power input port circuit, enabling it to operate stably in harsh power supply and electromagnetic interference environments.

[0010] In one optional embodiment, one end of the transient surge protection circuit is connected to the positive terminal of the power supply, and the other end is connected to the negative terminal of the power supply; the transient surge protection circuit includes a first surge circuit and a second surge circuit connected in parallel.

[0011] The first impact circuit is used to eliminate instantaneous voltage surges between the positive and negative terminals of the power supply.

[0012] The second impact circuit is used to eliminate instantaneous voltage surges between the positive and negative terminals of the power supply and the ground terminal.

[0013] In one optional implementation, the first impact circuit is a first ceramic gas discharge tube;

[0014] The second impact circuit includes a first varistor, a second varistor, and a second ceramic gas discharge tube; wherein, the first varistor and the second varistor form a first series circuit, one end of the first series circuit is connected to the positive terminal of the power supply, and the other end is connected to the negative terminal of the power supply; one end of the second ceramic gas discharge tube is connected to a first ground terminal, and the other end is connected to a first node, the first node being located between the first varistor and the second varistor.

[0015] In this embodiment, the varistor has a nonlinear voltage-current characteristic, exhibiting high impedance under normal operating voltage, while its resistance drops sharply when the voltage exceeds its threshold. This provides voltage clamping when the voltage exceeds its threshold, limiting the rate of voltage rise and peak value, thereby protecting subsequent circuits from damage caused by transient high voltage. Preferably, the second ceramic gas discharge tube has a fast response characteristic, enabling it to quickly conduct when a transient voltage surge occurs, guiding the overvoltage to ground, thereby further protecting the circuit. By combining the advantages of the varistor and the ceramic gas discharge tube, this embodiment effectively suppresses transient destructive interference between the positive and negative terminals of the power supply and the ground terminal, thereby improving the reliability and stability of the circuit.

[0016] In one optional implementation, the common-mode filter circuit includes a first common-mode filter circuit;

[0017] The first common-mode filter circuit includes a first common-mode filter capacitor bank and a first common-mode inductor; wherein, the first common-mode filter capacitor bank includes a second series circuit formed by a first capacitor and a second capacitor, one end of the second series circuit is connected to the positive terminal of the power supply, and the other end is connected to the negative terminal of the power supply; the second node located between the first capacitor and the second capacitor is connected to the second ground terminal; the first port of the first common-mode inductor is connected to the positive terminal of the power supply, and the second port is connected to the negative terminal of the power supply.

[0018] The embodiments of this application increase the total capacitance value of the common-mode filter circuit by using a first common-mode filter capacitor group composed of a first capacitor and a second capacitor, thereby improving the suppression capability of common-mode interference, enhancing the stability of the circuit, and reducing electromagnetic interference.

[0019] This application embodiment utilizes the DC-blocking characteristic of the first common-mode inductor to effectively filter out common-mode AC interference, which helps reduce ripple and noise on the power line, thereby making the power supply of the subsequent circuit more stable and smooth, and thus greatly improving the performance and reliability of the circuit; wherein, DC-blocking means allowing DC to pass through while blocking AC to pass through.

[0020] In one optional implementation, the common-mode filter circuit further includes a second common-mode filter circuit;

[0021] The second common-mode filter circuit includes a second common-mode filter capacitor bank and a second common-mode inductor; wherein, the second common-mode filter capacitor bank includes a third series circuit formed by a third capacitor and a fourth capacitor, one end of the third series circuit is connected to the third port of the first common-mode inductor, and the other end is connected to the fourth port of the first common-mode inductor; a third node located between the third capacitor and the fourth capacitor is connected to a third ground terminal; the first port of the second common-mode inductor is connected to the third port of the first common-mode inductor, and the second port of the second common-mode inductor is connected to the fourth port of the first common-mode inductor.

[0022] This embodiment of the application provides an additional filtering stage through the second common-mode filter capacitor bank, cascaded with the first common-mode filter capacitor bank, enhancing the suppression capability of common-mode interference and ensuring that interference is filtered out more thoroughly. Furthermore, the first and second common-mode filter capacitor banks enable multi-stage filtering, providing a wider frequency response and higher filtering efficiency. Each filtering stage operates for a specific frequency range, and multi-stage cascading can cover a wider frequency range.

[0023] This embodiment of the application significantly improves the suppression capability of common-mode AC interference through the coordinated action of the first and second common-mode inductors. Because each inductor impedes the interference signal, the interference signal is gradually attenuated, resulting in more effective suppression of ripple and noise on the power line, thus providing a smoother power supply for subsequent circuits. Furthermore, by increasing the number of common-mode inductors, this embodiment of the application can expand the frequency range of interference suppression. Different inductors may have different suppression effects on interference at different frequencies; the combination of two inductors can more comprehensively cover possible interference frequencies.

[0024] In one optional implementation, the transient shock protection circuit further includes a third shock circuit;

[0025] The third impact circuit is used to eliminate instantaneous voltage surges caused by electrostatic discharge in the circuit.

[0026] The third impulse circuit includes a fourth series circuit formed by a first bidirectional transient voltage suppressor diode and a second bidirectional transient voltage suppressor diode. One end of the fourth series circuit is connected to the third port of the first common mode inductor, and the other end is connected to the fourth port of the first common mode inductor. The fourth node located between the first bidirectional transient voltage suppressor diode and the second bidirectional transient voltage suppressor diode is connected to the fourth ground terminal.

[0027] In this embodiment, although the third impact circuit is a transient impact protection circuit like the first and second impact circuits, the third impact circuit includes a first bidirectional transient voltage suppression diode and a second bidirectional transient voltage suppression diode. The bidirectional transient voltage suppression diode typically has a faster response speed and a higher withstand voltage value than ceramic gas discharge tubes and varistors. Therefore, compared with the first and second impact circuits, the third impact circuit has a faster response speed and a higher withstand voltage value, enabling the third impact circuit to effectively eliminate electrostatic shocks on the circuit and thus protect the subsequent circuits.

[0028] In one optional embodiment, the differential mode filter circuit includes a fifth capacitor, a sixth capacitor, and a seventh capacitor forming a parallel circuit.

[0029] One end of the parallel circuit is connected to the third port of the second common-mode inductor, and the other end is connected to the fourth port of the second common-mode inductor; the subsequent circuit is connected to the third port and the fourth port.

[0030] In one alternative implementation, the fifth capacitor, the sixth capacitor, and the seventh capacitor are three capacitors with different capacitance values.

[0031] In this embodiment, the fifth, sixth, and seventh capacitors with different capacitance values ​​form an ultra-wide frequency filtering circuit, which can effectively filter out a wide range of differential-mode interference in the circuit.

[0032] In one alternative embodiment, the differential mode filter circuit includes an eighth capacitor, with one end of the second capacitor connected to the positive terminal of the power supply and the other end connected to the negative terminal of the power supply.

[0033] In this embodiment, since the eighth capacitor is directly connected between the positive and negative terminals of the power line, it can directly filter differential-mode interference on the power line. Because the capacitor presents low impedance to AC signals (differential-mode interference is typically in AC form), it can effectively bypass differential-mode interference to ground. Furthermore, when the eighth capacitor is connected across the power line, it, together with the inductance and resistance of the power line, forms a low-pass filter. This filter allows DC or low-frequency signals to pass through while blocking high-frequency differential-mode interference.

[0034] The reason why the eighth capacitor in this embodiment can effectively filter out differential-mode interference is that it utilizes the basic characteristics of capacitors (presenting low impedance to high-frequency signals) and circuit design principles (forming a low-pass filter), thereby achieving effective suppression of differential-mode interference.

[0035] In one alternative implementation, the cause includes at least one of the following: lightning strike, equipment switching operation, electrostatic discharge, and equipment failure.

[0036] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0037] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 This is a schematic diagram of an anti-interference power input port circuit according to an embodiment of the present invention;

[0039] Figure 2 This is a schematic diagram of another anti-interference power input port circuit according to an embodiment of the present invention. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] This embodiment provides an anti-interference power input port circuit. Figure 1 This is a schematic diagram of the anti-interference power input port circuit according to an embodiment of the present invention, as shown below. Figure 1 As shown, the anti-interference power input port circuit includes a transient response protection circuit, a common-mode filter circuit, and a differential-mode filter circuit.

[0042] The transient surge protection circuit is used to eliminate transient voltage surges caused by various reasons.

[0043] Specifically, transient voltage surges refer to sudden changes in circuit voltage, such as a rapid increase in circuit voltage within a short period of time. This voltage may be far higher than the normal operating voltage range of the equipment, easily causing equipment damage, circuit board burnout, and data loss. Causes of transient voltage surges include at least one of the following: lightning strikes, equipment switching operations, electrostatic discharge, and equipment malfunction.

[0044] The common-mode filter circuit is used to filter common-mode interference on the circuit.

[0045] Specifically, common-mode interference refers to voltage fluctuations in the same direction that occur simultaneously on two or more conductors (such as power lines, signal lines, etc.) in a circuit. It can easily cause voltage fluctuations on power lines, affecting the stability of the power supply and thus the overall performance of the entire system. Since common-mode interference is in the same direction on all relevant conductors, common-mode inductors or common-mode capacitors can be used to effectively suppress this interference.

[0046] The differential mode filter circuit is used to filter differential mode interference on the circuit.

[0047] Specifically, differential-mode interference refers to voltage fluctuations that occur between two or more conductors in a circuit. The voltage of this interference is opposite in direction on different conductors, which may cause problems such as signal distortion, data errors or equipment damage.

[0048] This application embodiment effectively filters out interference of different modes by coordinating the common-mode filter circuit and the differential-mode filter circuit, thereby improving the circuit's anti-interference capability. Through the coordinated action of the transient surge protection circuit, the common-mode filter circuit, and the differential-mode filter circuit, comprehensive protection of the power input port can be achieved. It can not only cope with transient voltage surges but also suppress electromagnetic interference, providing more comprehensive protection. This improves the reliability of the entire power input port circuit, enabling it to operate stably in harsh power supply and electromagnetic interference environments.

[0049] In some specific embodiments, one end of the transient surge protection circuit is connected to the positive terminal of the power supply, and the other end is connected to the negative terminal of the power supply; the transient surge protection circuit includes a first surge circuit and a second surge circuit connected in parallel;

[0050] The first impact circuit is used to eliminate instantaneous voltage surges between the positive and negative terminals of the power supply.

[0051] Specifically, the instantaneous voltage surge between the positive and negative terminals of the power supply is caused by lightning strikes and equipment switching operations.

[0052] In some specific embodiments, such as Figure 2 As shown: The first impact circuit can be the first ceramic gas discharge tube D1, which is mainly used to eliminate the damage caused by the instantaneous surge voltage generated by lightning strikes and equipment switching operations between the positive and negative poles, thereby protecting the subsequent circuits.

[0053] The second impact circuit is used to eliminate instantaneous voltage surges between the positive and negative terminals of the power supply and the ground terminal.

[0054] In some specific embodiments, such as Figure 2 As shown: The second impact circuit includes a first varistor R1, a second varistor R2, and a second ceramic gas discharge tube D2.

[0055] Specifically, a first series circuit is formed by the first varistor R1 and the second varistor R2, with one end of the first series circuit connected to the positive terminal of the power supply and the other end connected to the negative terminal of the power supply; one end of the second ceramic gas discharge tube D2 is connected to the first ground terminal G1 and the other end is connected to the first node, which is located between the first varistor R1 and the second varistor R2.

[0056] In this embodiment, the second impulse circuit, composed of a first varistor R1, a second varistor R2, and a second ceramic gas discharge tube D2, is mainly used to eliminate transient destructive interference between the positive and negative terminals of the power supply and the ground terminal.

[0057] In this embodiment, the varistor has a nonlinear voltage-current characteristic, exhibiting high impedance under normal operating voltage, while its resistance drops sharply when the voltage exceeds its threshold. This provides voltage clamping when the voltage exceeds its threshold, limiting the rate of voltage rise and peak value, thereby protecting subsequent circuits from damage caused by transient high voltage. Preferably, the second ceramic gas discharge tube D2 has a fast response characteristic, enabling it to quickly conduct when a transient voltage surge occurs, guiding the overvoltage to ground, thereby further protecting the circuit. By combining the advantages of the varistor and the ceramic gas discharge tube, this embodiment effectively suppresses transient destructive interference between the positive and negative terminals of the power supply and the ground terminal, thereby improving the reliability and stability of the circuit.

[0058] In some specific embodiments, such as Figure 2 As shown, the common-mode filter circuit includes a first common-mode filter circuit; the first common-mode filter circuit includes a first common-mode filter capacitor bank and a first common-mode inductor L1.

[0059] Specifically, the first common-mode filter capacitor bank includes a second series circuit formed by a first capacitor C1 and a second capacitor C2. One end of the second series circuit is connected to the positive terminal of the power supply, and the other end is connected to the negative terminal of the power supply. The second node located between the first capacitor C1 and the second capacitor C2 is connected to the second ground terminal G2. The first port of the first common-mode inductor L1 is connected to the positive terminal of the power supply, and the second port is connected to the negative terminal of the power supply.

[0060] The embodiments of this application increase the total capacitance of the common-mode filter circuit by using a first common-mode filter capacitor group composed of a first capacitor C1 and a second capacitor C2, thereby improving the suppression capability of common-mode interference, enhancing the stability of the circuit, and reducing electromagnetic interference.

[0061] This embodiment utilizes the DC-blocking characteristic of the first common-mode inductor L1 to effectively filter out common-mode AC interference, which helps reduce ripple and noise on the power line, thereby making the power supply of the subsequent circuit more stable and smooth, and thus greatly improving the performance and reliability of the circuit; wherein, DC-blocking means allowing DC to pass through while blocking AC to pass through.

[0062] In some specific embodiments, the first capacitor C1 and the second capacitor C2 have the same capacitance value. The first common-mode filter capacitor group composed of the first capacitor C1 and the second capacitor C2 is mainly used to filter out common-mode current interference in the circuit.

[0063] This embodiment of the application uses two capacitors with the same capacitance value to provide a balanced filtering effect, ensuring effective suppression of common-mode interference on both the positive and negative terminals of the power supply. Furthermore, balanced common-mode filtering reduces electromagnetic interference emissions and improves the electromagnetic compatibility of the circuit.

[0064] In some specific embodiments, such as Figure 2 As shown: The common-mode filter circuit further includes a second common-mode filter circuit; the second common-mode filter circuit includes a second common-mode filter capacitor bank and a second common-mode inductor L2.

[0065] Specifically, the second common-mode filter capacitor group includes a third series circuit formed by a third capacitor C3 and a fourth capacitor C4. One end of the third series circuit is connected to the third port of the first common-mode inductor L1, and the other end is connected to the fourth port of the first common-mode inductor L1. The third node located between the third capacitor C3 and the fourth capacitor C4 is connected to the third ground terminal G3. The first port of the second common-mode inductor L2 is connected to the third port of the first common-mode inductor L1, and the second port of the second common-mode inductor L2 is connected to the fourth port of the first common-mode inductor L1.

[0066] In this embodiment, the second common-mode filter capacitor group composed of the third capacitor C3 and the fourth capacitor C4 is mainly used to further filter out common-mode current interference in the circuit, so as to prevent the front-end circuit (i.e., the first common-mode filter capacitor group composed of the first capacitor C1 and the second capacitor C2) from not filtering it cleanly.

[0067] This embodiment of the application provides an additional filtering stage through the second common-mode filter capacitor bank, cascaded with the first common-mode filter capacitor bank, enhancing the suppression capability of common-mode interference and ensuring that interference is filtered out more thoroughly. Furthermore, the first and second common-mode filter capacitor banks enable multi-stage filtering, providing a wider frequency response and higher filtering efficiency. Each filtering stage operates for a specific frequency range, and multi-stage cascading can cover a wider frequency range.

[0068] In this embodiment, the second common-mode inductor L2 and the first common-mode inductor L1 have the same function. In this invention, the second common-mode inductor L2 is used to further filter out common-mode AC interference, thereby making the ripple of the subsequent circuit smoother.

[0069] This embodiment of the application, through the coordinated action of the first common-mode inductor L1 and the second common-mode inductor L2, can significantly improve the suppression capability of common-mode AC interference. This is because each inductor impedes the interference signal, thereby achieving a step-by-step weakening of the interference signal and more effectively suppressing ripple and noise on the power line, thus providing a smoother power supply for subsequent circuits. Furthermore, by increasing the number of common-mode inductors, this embodiment of the application can expand the frequency range of interference suppression. Different inductors may have different suppression effects on interference at different frequencies; the combination of two inductors can more comprehensively cover possible interference frequencies.

[0070] In some specific embodiments, the anti-transient shock circuit further includes a third shock circuit; the third shock circuit is used to eliminate instantaneous voltage surges on the circuit caused by electrostatic discharge.

[0071] Specifically, if Figure 2 As shown: The third impulse circuit includes a fourth series circuit formed by the first bidirectional transient voltage suppression diode T1 and the second bidirectional transient voltage suppression diode T2. One end of the fourth series circuit is connected to the third port of the first common mode inductor L1, and the other end is connected to the fourth port of the first common mode inductor L1. The fourth node located between the first bidirectional transient voltage suppression diode T1 and the second bidirectional transient voltage suppression diode T2 is connected to the fourth ground terminal G4.

[0072] In this embodiment, although the third impact circuit is the same as the first and second impact circuits mentioned above as transient impact protection circuits, the third impact circuit includes a first bidirectional transient voltage suppression diode T1 and a second bidirectional transient voltage suppression diode T2. The bidirectional transient voltage suppression diode usually has a faster response speed and a higher withstand voltage value than the ceramic gas discharge tube and the varistor. Therefore, compared with the first and second impact circuits, the third impact circuit has a faster response speed and a higher withstand voltage value, which enables the third impact circuit to effectively eliminate electrostatic shocks on the circuit, thereby protecting the subsequent circuits.

[0073] In some specific embodiments, such as Figure 2 As shown: The differential mode filter circuit includes a fifth capacitor C5, a sixth capacitor C6, and a seventh capacitor C7 connected in parallel.

[0074] Specifically, one end of the parallel circuit is connected to the third port of the second common-mode inductor L2, and the other end is connected to the fourth port of the second common-mode inductor L2; the subsequent circuit is connected to the third port and the fourth port.

[0075] In some specific embodiments, the fifth capacitor C5 is an electrolytic capacitor, mainly used for storing energy, smoothing voltage, or filtering low-frequency signals.

[0076] In some specific embodiments, the fifth capacitor C5, the sixth capacitor C6, and the seventh capacitor C7 are three capacitors with different capacitance values.

[0077] Specifically, the capacitance values ​​of the fifth capacitor C5, the sixth capacitor C6, and the seventh capacitor C7 can be set according to the actual situation, and no specific limitation is made here. For example, the capacitance value of C5 can be in the hundreds of uf level, the capacitance value of C6 can be in the tens of uf level, and the capacitance value of C7 can be in the nf level.

[0078] In this embodiment, the fifth capacitor C5, the sixth capacitor C6, and the seventh capacitor C7, with different capacitance values, form an ultra-wide frequency filter circuit, which can effectively filter out a wide range of differential mode interference on the circuit.

[0079] In some specific embodiments, the differential mode filter circuit includes an eighth capacitor C8, and one end of the second capacitor C2 is connected to the positive terminal of the power supply, and the other end is connected to the negative terminal of the power supply.

[0080] In this embodiment, since the eighth capacitor C8 is directly connected between the positive and negative terminals of the power line, it can directly filter differential-mode interference on the power line. Because the capacitor presents low impedance to AC signals (differential-mode interference is typically in AC form), it can effectively bypass differential-mode interference to ground. Furthermore, when the eighth capacitor C8 is connected across the power line, it, together with the inductance and resistance of the power line, forms a low-pass filter. This filter allows DC or low-frequency signals to pass through while blocking high-frequency differential-mode interference.

[0081] The reason why the eighth capacitor in this embodiment can effectively filter out differential-mode interference is that it utilizes the basic characteristics of capacitors (presenting low impedance to high-frequency signals) and circuit design principles (forming a low-pass filter), thereby achieving effective suppression of differential-mode interference.

[0082] In the embodiments of this application, the first capacitor C1, the second capacitor C2, the third capacitor C3, the fourth capacitor C4, the fifth capacitor C5, the sixth capacitor C6, the seventh capacitor C7, the eighth capacitor C8, the first common-mode inductor L1, and the second common-mode inductor L2 form a two-stage π-type filter circuit, which can attenuate ripple more thoroughly, cover a wider frequency range, adapt to loads more effectively, and reduce the parameter requirements of components.

[0083] In the embodiments of this application, the parameters of all electronic components involved are not specified and can be flexibly adjusted according to actual applications.

[0084] It should be noted that:

[0085] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known structures and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0086] Similarly, it should be understood that, for the sake of brevity and to aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of this application, various features of this application are sometimes grouped together in a single embodiment, figure, or description thereof. However, this disclosure should not be construed as reflecting a schematic diagram in which the claimed application requires more features than expressly recited in each claim. Rather, as reflected in the following claims, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0087] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0088] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An anti-interference power input port circuit, characterized in that, The power input port circuit includes a transient response protection circuit, a common-mode filter circuit, and a differential-mode filter circuit. The transient voltage surge protection circuit is used to eliminate transient voltage surges caused by various reasons; the transient voltage surge refers to a sudden change in circuit voltage. The common-mode filter circuit is used to filter common-mode interference on the circuit. The differential mode filter circuit is used to filter differential mode interference on the circuit.

2. The anti-interference power input port circuit according to claim 1, characterized in that, One end of the transient shock protection circuit is connected to the positive terminal of the power supply, and the other end is connected to the negative terminal of the power supply; the transient shock protection circuit includes a first shock circuit and a second shock circuit connected in parallel; The first impact circuit is used to eliminate instantaneous voltage surges between the positive and negative terminals of the power supply. The second impact circuit is used to eliminate instantaneous voltage surges between the positive and negative terminals of the power supply and the ground terminal.

3. The anti-interference power input port circuit according to claim 2, characterized in that, The first impact circuit is a first ceramic gas discharge tube; The second impact circuit includes a first varistor, a second varistor, and a second ceramic gas discharge tube; wherein, the first varistor and the second varistor form a first series circuit, one end of the first series circuit is connected to the positive terminal of the power supply, and the other end is connected to the negative terminal of the power supply; one end of the second ceramic gas discharge tube is connected to a first ground terminal, and the other end is connected to a first node, the first node being located between the first varistor and the second varistor.

4. The anti-interference power input port circuit according to claim 1, characterized in that, The common-mode filter circuit includes a first common-mode filter circuit; The first common-mode filter circuit includes a first common-mode filter capacitor bank and a first common-mode inductor; wherein, the first common-mode filter capacitor bank includes a second series circuit formed by a first capacitor and a second capacitor, one end of the second series circuit is connected to the positive terminal of the power supply, and the other end is connected to the negative terminal of the power supply; the second node located between the first capacitor and the second capacitor is connected to the second ground terminal; the first port of the first common-mode inductor is connected to the positive terminal of the power supply, and the second port is connected to the negative terminal of the power supply.

5. The anti-interference power input port circuit according to claim 4, characterized in that, The common-mode filter circuit also includes a second common-mode filter circuit; The second common-mode filter circuit includes a second common-mode filter capacitor bank and a second common-mode inductor; wherein, the second common-mode filter capacitor bank includes a third series circuit formed by a third capacitor and a fourth capacitor, one end of the third series circuit is connected to the third port of the first common-mode inductor, and the other end is connected to the fourth port of the first common-mode inductor; a third node located between the third capacitor and the fourth capacitor is connected to a third ground terminal; the first port of the second common-mode inductor is connected to the third port of the first common-mode inductor, and the second port of the second common-mode inductor is connected to the fourth port of the first common-mode inductor.

6. The anti-interference power input port circuit according to claim 5, characterized in that, The transient impact protection circuit also includes a third impact circuit; The third impact circuit is used to eliminate instantaneous voltage surges caused by electrostatic discharge in the circuit. The third impulse circuit includes a fourth series circuit formed by a first bidirectional transient voltage suppressor diode and a second bidirectional transient voltage suppressor diode. One end of the fourth series circuit is connected to the third port of the first common mode inductor, and the other end is connected to the fourth port of the first common mode inductor. The fourth node located between the first bidirectional transient voltage suppressor diode and the second bidirectional transient voltage suppressor diode is connected to the fourth ground terminal.

7. The anti-interference power input port circuit according to claim 5, characterized in that, The differential mode filter circuit includes a fifth capacitor, a sixth capacitor, and a seventh capacitor forming a parallel circuit. One end of the parallel circuit is connected to the third port of the second common-mode inductor, and the other end is connected to the fourth port of the second common-mode inductor; the subsequent circuit is connected to the third port and the fourth port.

8. The anti-interference power input port circuit according to claim 7, characterized in that, The fifth capacitor, the sixth capacitor, and the seventh capacitor are three capacitors with different capacitance values.

9. The anti-interference power input port circuit according to claim 5, characterized in that, The differential mode filter circuit includes an eighth capacitor, one end of the second capacitor is connected to the positive terminal of the power supply, and the other end is connected to the negative terminal of the power supply.

10. The anti-interference power input port circuit according to claim 1 or 2, characterized in that, The causes include at least one of the following: lightning strikes, equipment switching operations, electrostatic discharge, and equipment malfunction.

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