Lightning protection device and electronic equipment

Abstract

The invention provides a lightning protection device and electronic equipment, the lightning protection device comprises a substrate layer, a first metal layer, a radio frequency coaxial line, a lightning protection structure and a radio frequency line, the first surface of the substrate layer is provided with a first bonding pad and a second bonding pad; the first metal layer is arranged on the first surface, is electrically connected with the first bonding pad and is separated from the second bonding pad; the radio frequency coaxial line is arranged on the first surface and comprises an inner conductor, a dielectric layer and an outer conductor which are sequentially arranged from inside to outside, the outer conductor is welded with the first bonding pad, and the inner conductor is welded with the second bonding pad; the lightning protection structure is arranged on the first surface, the lightning protection structure is electrically connected with the second bonding pad and the first metal layer, and the lightning protection structure is configured to access at least two signals of different frequency bands to the first metal layer under the condition of lightning stroke; the radio frequency line is arranged on the first surface and is electrically connected with the second bonding pad. According to the invention, signals of at least two different frequency bands can be protected, high cost caused by multiple metal layers is avoided, the cost is reduced, and the occupied space is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrical protection, in particular to a lightning protection device and an electronic device. BACKGROUND

[0002] Lightning protection devices are widely used in communication equipment to protect circuit systems from lightning strikes or electrostatic discharge and other overvoltage phenomena. Especially in high-frequency communication systems, such as 5G, Wi-Fi and other applications, the signal transmission between the antenna and the radio frequency link is more sensitive to electromagnetic interference and transient overvoltage, so it is necessary to integrate an efficient lightning protection device in the circuit design.

[0003] In the prior art, some lightning protection devices achieve lightning protection for multiple frequency bands by using multiple substrate layers and multiple metal layers, resulting in increased overall cost and large space occupation. SUMMARY

[0004] The embodiments of the present application provide a lightning protection device and an electronic device, which can reduce cost and space occupation.

[0005] The technical scheme of the embodiments of the present application is as follows: The first aspect of the present application provides a lightning protection device, comprising: a substrate layer, a first surface of the substrate layer being provided with a first pad and a second pad, the first pad and the second pad being arranged at intervals; a first metal layer, arranged on the first surface, the first metal layer being electrically connected to the first pad and arranged at intervals from the second pad; a radio frequency coaxial line, arranged on the first surface, and comprising an inner conductor, a dielectric layer and an outer conductor arranged in sequence from inside to outside, the outer conductor being welded to the first pad, and the inner conductor being welded to the second pad; a lightning protection structure, arranged on the first surface, the lightning protection structure being electrically connected to the second pad and electrically connected to the first metal layer, the lightning protection structure being configured to connect signals of at least two different frequency bands to the first metal layer in the event of a lightning strike; and a radio frequency line, arranged on the first surface and arranged at intervals from the first metal layer, the radio frequency line being electrically connected to the second pad.

[0006] In some embodiments, the lightning protection structure comprises a microstrip short circuit line and a wave trap, one end of the microstrip short circuit line being electrically connected to the second pad, the other end of the microstrip short circuit line being electrically connected to the first metal layer, and the wave trap being connected in parallel with the microstrip short circuit line.

[0007] In some embodiments, the wave trap comprises at least two LC parallel resonance circuits, at least one LC parallel resonance circuit being arranged on each of the opposite sides of the microstrip short circuit line along the width direction of the microstrip short circuit line, and each LC parallel resonance circuit being connected in parallel with the microstrip short circuit line.

[0008] In some embodiments, the thickness direction of the substrate layer is the first direction, the microstrip short circuit line and the RF coaxial line both extend along the second direction and are arranged along the second direction, the ends of the inner conductors of the microstrip short circuit line and the RF coaxial line close to each other are electrically connected through the second pad, and the RF line extends along the third direction, the first direction, the second direction, and the third direction are orthogonal to each other.

[0009] In some embodiments, the microstrip short circuit line and the RF coaxial line are located at the middle position of the first surface along the third direction; and / or, the RF line is located at the middle position of the first surface along the second direction.

[0010] In some embodiments, the lightning protection device further comprises a second metal layer, the second metal layer is arranged on the second surface of the substrate layer, the second surface and the first surface are respectively two surfaces of the substrate layer opposite along the thickness direction thereof, and the second metal layer is electrically connected with the first metal layer.

[0011] In some embodiments, the substrate layer is formed with a through hole penetrating through along the thickness direction thereof, and the second metal layer is electrically connected with the first metal layer through the conductive part arranged in the through hole.

[0012] In some embodiments, the conductive part is a metal plating layer formed on the hole wall of the through hole.

[0013] In some embodiments, the first metal layer is made of copper.

[0014] A second aspect of the present application provides an electronic device comprising the lightning protection device provided in the first aspect.

[0015] The embodiments of the present application have the following beneficial effects: The lightning protection device provided in the embodiments of the present application can prevent at least two signals of different frequency bands from passing through the lightning protection structure under normal circumstances, that is, the at least two signals of different frequency bands cannot access the first metal layer and can be transmitted to the inner conductor of the RF coaxial line through the second pad and then sent out by the RF coaxial line; when lightning strikes occur, high-voltage signals are transmitted to the second pad through the external antenna and the inner conductor of the RF coaxial line, in this case, the lightning protection structure allows the at least two signals of different frequency bands to pass through and be transmitted to the first metal layer, and then the signals are transmitted to the outer conductor of the RF coaxial line through the first metal layer and the first pad, at this time, the potential difference between the outer conductor and the inner conductor is relatively small and is not easy to cause breakdown, thereby achieving the effect of protecting the substrate layer; in this way, the lightning protection device uses a single substrate layer to achieve multi-frequency lightning protection, avoids high cost and complex processing caused by multiple substrate layers, has a small size and low manufacturing cost, and therefore, the lightning protection device provided in the embodiments of the present application reduces cost and occupies less space. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1is a top view of a first structure of a lightning protection device provided by an embodiment of the present application; Figure 2 is a front view of the first structure of the lightning protection device provided by the embodiment of the present application; Figure 3 is a top view of a second structure of a lightning protection device provided by an embodiment of the present application; Figure 4 is a front view of the second structure of the lightning protection device provided by the embodiment of the present application; Figure 5 is a simulation result graph of an S11 parameter of a lightning protection device provided by an embodiment of the present application; Figure 6 is a simulation result graph of an S21 parameter of a lightning protection device provided by an embodiment of the present application; Figure 7 is a comparison graph of a tuning capacitance value S11 of a lightning protection device provided by an embodiment of the present application; Figure 8 is a comparison graph of a tuning capacitance value S21 of a lightning protection device provided by an embodiment of the present application; Figure 9 is a comparison graph of a tuning microstrip short-circuit line length S11 of a lightning protection device provided by an embodiment of the present application; Figure 10 is a comparison graph of a tuning microstrip short-circuit line length S21 of a lightning protection device provided by an embodiment of the present application; Figure 11 is a structural schematic diagram of an electronic device provided by an embodiment of the present application.

[0017] Legend of reference signs 1, first pad; 2, second pad; 3, second interval; 4, lumped inductance; 5, microstrip stub; 6, microstrip short-circuit line; 7, first interval; 8, lumped capacitance; 9, radio frequency line; 10, radio frequency coaxial line; 11, first metal layer; 12, through hole; 13, second metal layer; 14, substrate layer; 15, LC parallel resonant circuit; X, first direction; Y, second direction; Z, third direction; 1000, electronic device; 100, lightning protection device; 200, case interface; 300, antenna; 400, combiner; 501, 2.4G radio frequency front-end module; 502, 2.4G matching circuit; 601, 5G radio frequency front-end module; 602, 5G matching circuit. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be described in further detail below with reference to the drawings, and the described embodiments should not be regarded as limiting the present application, and all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present application.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application; the use of the terms "including," "comprising," or "having" and variations thereof herein is intended to be broad and encompass the terms "consisting of" and "consisting essentially of" and variations thereof. The use of the term "about" in relation to a geographic location refers to a location within a 10 km radius of the geographic location.

[0020] In the description of the embodiments of the present application, the technical terms "first", "second", "third" and the like are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0021] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification are not necessarily all referring to the same embodiment, or are necessarily referring to different or alternative embodiments to one another. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0022] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are "or" relationship.

[0023] In the description of the embodiments of the present application, the technical terms "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and are not intended to indicate or imply that the indicated device or element must have a particular orientation, be constructed, operated or used in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0024] In the description of the embodiments of the present application, unless explicitly defined and limited otherwise, the technical terms "mounting", "connecting", "connecting", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above-mentioned terms in the embodiments of the present application can be understood according to the specific circumstances.

[0025] In the description of the embodiments of the present application, unless explicitly defined and limited otherwise, the technical term "contact" should be understood in a broad sense, which can be direct contact or contact through an intermediate medium layer, and can be contact between two objects in contact without interaction force, or contact between two objects in contact with interaction force.

[0026] Next, the present application will be described in detail.

[0027] The lightning protection device is widely used in communication equipment to protect the circuit system from lightning or electrostatic discharge and other overvoltage phenomena. Especially in high-frequency communication systems, such as 5G, Wi-Fi and other applications, the signal transmission between the antenna and the radio frequency link is more sensitive to electromagnetic interference and transient overvoltage, so it is necessary to integrate an efficient lightning protection device in the circuit design.

[0028] In the prior art, some lightning protection devices achieve lightning protection for multi-band signals by using multiple substrate layers and multiple metal layers, resulting in increased overall cost and large space occupation.

[0029] Therefore, the present application designs a lightning protection device capable of reducing space occupation and cost.

[0030] The following will be described in conjunction with the accompanying drawings Figures 1 to 10 Some embodiments of the present application will be described in detail.

[0031] Figure 1 is a top view of a first structure of a lightning protection device provided by the embodiments of the present application; Figure 2 is a front view of the first structure of the lightning protection device provided by the embodiments of the present application; Figure 3 is a top view of a second structure of a lightning protection device provided by the embodiments of the present application; Figure 4 is a front view of the second structure of the lightning protection device provided by the embodiments of the present application; Figure 5 is a S11 parameter simulation result graph of the lightning protection device provided by the embodiments of the present application; Figure 6 is a S21 parameter simulation result graph of the lightning protection device provided by the embodiments of the present application; Figure 7This is a comparison diagram of the tuning capacitor value S11 of the lightning protection device provided in the embodiments of this application; Figure 8 This is a comparison diagram of the tuning capacitor value S21 of the lightning protection device provided in the embodiments of this application; Figure 9 This is a comparison diagram of the tuning microstrip short-circuit length S11 of the lightning protection device provided in the embodiments of this application; Figure 10 This is a comparison diagram of the tuning microstrip short-circuit length S21 of the lightning protection device provided in the embodiments of this application; Figure 11 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application.

[0032] The first aspect of this application provides a lightning protection device 100, such as Figures 1 to 4 As shown, the lightning protection device 100 includes a substrate layer 14, a first metal layer 11, an RF coaxial cable 10, a lightning protection structure, and an RF line 9. The first surface of the substrate layer 14 is provided with a first pad 1 and a second pad 2, which are spaced apart. The first metal layer 11 is disposed on the first surface and is electrically connected to the first pad 1 and spaced apart from the second pad 2. The RF coaxial cable 10 is disposed on the first surface and includes an inner conductor, a dielectric layer, and an outer conductor arranged sequentially from the inside to the outside. The outer conductor is soldered to the first pad 1, and the inner conductor is soldered to the second pad 2. The lightning protection structure is disposed on the first surface and is electrically connected to the second pad 2 and the first metal layer 11. The lightning protection structure is configured to allow at least two signals of different frequency bands to be connected to the first metal layer 11 in the event of a lightning strike. The RF line 9 is disposed on the first surface and spaced apart from the first metal layer 11. The RF line 9 is electrically connected to the second pad 2.

[0033] Substrate layer 14 refers to the insulating substrate material used to support the circuit structure. It not only electrically isolates adjacent conductors but also serves as a "carrier" for electromagnetic wave transmission. It is usually made of FR-4 (a laminated composite material of epoxy resin and alkali-free fiberglass cloth) or other dielectric materials with good high-frequency performance, and has a specific thickness and dielectric constant. As the foundation of the circuit board, substrate layer 14 provides physical support and electrical isolation for conductor lines. For example, the substrate layer 14 is made of FR-4 material with a thickness of 1.6 mm and a relative permittivity of 4.3. Its loss tangent is 0.025.

[0034] For example, the edges of the first metal layer 11 are rectangular.

[0035] The first metal layer 11 refers to the metal layer located on the first surface of the substrate layer 14, used to construct the radio frequency signal transmission path and ground plane. This metal layer, through connection with other conductor structures, achieves signal transmission and electromagnetic shielding functions. For example, the first metal layer 11 may be made of, but is not limited to, copper.

[0036] The radio frequency coaxial line 10 includes an inner conductor and an outer conductor. The inner conductor of the radio frequency coaxial line 10 is electrically connected to the lightning protection structure through the second solder pad 2, and the outer conductor of the radio frequency coaxial line 10 is electrically connected to the first metal layer 11 through the first solder pad 1, so as to ensure effective transmission of signals and integrity of the lightning protection path.

[0037] The radio frequency line 9 is a transmission line connected to the second solder pad 2, and is used to transmit external radio frequency signals to the radio frequency coaxial line 10. For example, the radio frequency line 9 is a long strip of copper material.

[0038] For example, the second solder pad 2 is in an octagonal structure and is made of metal material. The first solder pad 1 is in a rectangular structure and is made of metal material. The first solder pad 1 has a long side of 120 mil and a short side of 92 mil.

[0039] For example, the lightning protection structure can protect signals in two different frequency bands, i.e., a 2.4G frequency band (2.412 GHz-2.482 GHz) and a 5G frequency band (5.15 GHz-5.825 GHz).

[0040] The lightning protection device 100 provided by the embodiment of the present application can prevent at least two different frequency bands of signals from passing through the lightning protection structure under normal circumstances, i.e., the at least two different frequency bands of signals cannot access the first metal layer 11, so that the signals transmitted from the input radio frequency line 9 can be transmitted to the inner conductor of the radio frequency coaxial line 10 through the second solder pad 2, and then be transmitted by the radio frequency coaxial line 10. When lightning strikes occur, high-voltage signals can be transmitted to the second solder pad 2 through the external antenna and the inner conductor of the radio frequency coaxial line 10. In this case, the lightning protection structure allows the at least two different frequency bands of signals to pass through and be transmitted to the first metal layer 11. Then, the high-voltage signals are transmitted to the outer conductor of the radio frequency coaxial line 10 through the first metal layer 11 and the first solder pad 1. At this time, the potential difference between the outer conductor and the inner conductor is relatively small, and the breakdown phenomenon is not easy to occur, thereby achieving the effect of protecting the substrate layer. The lightning protection device can effectively protect the subsequent radio frequency link and reduce the damage of lightning to the equipment. In this way, the lightning protection device uses a single substrate layer to achieve multi-frequency lightning protection, avoids high cost and complex processing caused by multiple substrate layers, has small size and low manufacturing cost. Therefore, the lightning protection device provided by the embodiment of the present application reduces the cost and reduces the occupation of space.

[0041] In some embodiments, the lightning protection structure includes a microstrip short circuit line 6 and a wave trap. One end of the microstrip short circuit line 6 is electrically connected to the second solder pad 2, and the other end is electrically connected to the first metal layer 11. The wave trap is connected in parallel with the microstrip short circuit line 6.

[0042] The microstrip short-circuit line 6 can be a microstrip line segment with a length of about one quarter of a wavelength at the operating frequency, one end of which is connected to the first metal layer 11 and the other end of which is connected to the RF coaxial line 10. Under normal circumstances, the microstrip short-circuit line 6 is equivalent to an open circuit at its center frequency point to inhibit the passage of RF signals, but conducts and discharges lightning energy, thereby playing a lightning protection role.

[0043] For example, the length of the microstrip short-circuit line 6 can be, but is not limited to, one quarter of a wavelength at a 5G frequency.

[0044] Specifically, the wave trap is electrically connected to the microstrip short-circuit line 6 and the first metal layer 11.

[0045] The wave trap is used to generate a high impedance characteristic at a specific frequency band to suppress interference signals.

[0046] For example, the wave trap uses a 2.4G wave trap, which is an electronic filter used to suppress or eliminate specific frequency signals in the 2.4GHz frequency band. It belongs to a type of band-stop filter, and its core function is to reflect electromagnetic signals in the 2.4GHz frequency band (such as 2.412-2.482GHz) and prevent them from passing through. The 2.4GHz useful signal is connected to the ground through the microstrip short-circuit line 6, and the useful signal is guided to pass along the RF coaxial line 10.

[0047] In this way, by connecting the wave trap in parallel to the microstrip short-circuit line 6, the signals of two specific frequency bands, such as 2.4GHz and 5GHz, can be effectively protected at the same time, the insertion loss of the lightning protection device 100 in a large interval operating frequency band can be reduced, and the return loss can be reduced. Moreover, a single metal layer and a single substrate layer 14 can be used to achieve dual-frequency microstrip lightning protection, avoiding the high cost and processing complexity of multiple metal layers, while optimizing the electromagnetic characteristics by controlling the current distribution, thereby improving the return loss performance, reducing the insertion loss, and improving the signal transmission efficiency.

[0048] In some embodiments, as shown in Figure 1 The wave trap includes at least two LC parallel resonance circuits 15, and at least one LC parallel resonance circuit 15 is arranged on each of the opposite sides of the microstrip short-circuit line 6 in the width direction thereof, and each LC parallel resonance circuit 15 is connected in parallel to the microstrip short-circuit line 6.

[0049] The LC parallel resonance circuit 15 is a circuit composed of an inductor (L) and a capacitor (C) in parallel, and its core characteristic is to exhibit maximum impedance at a specific resonance frequency, thereby achieving a frequency selection function. For example, the circuit can form a high-impedance path at 2.4GHz through the parallel resonance characteristic, effectively suppressing lightning surge signals, while maintaining the transmission of normal communication signals.

[0050] Exemplarily, the two LC parallel resonant circuits 15 are respectively arranged on opposite sides of the microstrip short-circuit line 6 and are symmetrical about the microstrip short-circuit line 6.

[0051] Exemplarily, the LC parallel resonant circuit 15 includes a lumped inductor 4 and a lumped capacitor 8 in parallel.

[0052] In this way, by arranging two LC parallel resonant circuits 15, different frequencies can be tuned to respectively, so as to provide more accurate resonance suppression effect in the dual-band, thereby enhancing the stability and reliability of the lightning protection device 100 in multiple frequency bands, and making the overall performance more balanced.

[0053] Of course, it can be understood that the wave trap is not limited to two LC parallel resonant circuits 15, and in some embodiments, the wave trap can adopt, but is not limited to, an LC series resonant wave trap, an LC series resonant wave trap, and the like.

[0054] In some embodiments, as shown in Figure 1 and Figure 2 , the thickness direction of the substrate layer 14 is the first direction X, the microstrip short-circuit line 6 and the radio frequency coaxial line 10 extend along the second direction Y and are arranged along the second direction Y, the ends of the inner conductors of the microstrip short-circuit line 6 and the radio frequency coaxial line 10 close to each other are electrically connected through the second pad 2, and the radio frequency line 9 extends along the third direction Z. The first direction X, the second direction Y and the third direction Z are orthogonal to each other.

[0055] In this way, by reasonably arranging the directions and positions of the elements, the size of the entire lightning protection device 100 is compact, which is conducive to integrated application in limited space, while avoiding interference between signals of different directions and improving the stability and electromagnetic compatibility of the overall structure.

[0056] In some embodiments, as shown in Figure 1 and Figure 2 , the microstrip short-circuit line 6 and the radio frequency coaxial line 10 are located at the middle position of the first surface along the third direction Z; and / or the radio frequency line 9 is located at the middle position of the first surface along the second direction Y.

[0057] In this way, by arranging the key elements at the center position, it is helpful to balance the current distribution and signal transmission path, reduce signal distortion or interference caused by asymmetric layout, and thereby improve the performance of the lightning protection device 100 when working at high frequency.

[0058] In some embodiments, as shown in Figure 1 , the lightning protection structure includes two LC parallel resonant circuits 15 in parallel, both of which are in parallel with the microstrip short-circuit line 6 and are symmetrically arranged on opposite sides of the microstrip short-circuit line 6 along the third direction Z.

[0059] Exemplarily, the two LC parallel resonant circuits 15 and the microstrip short-circuit line 6 each have the first interval 7 in the third direction Z. The two LC parallel resonant circuits 15 each have the second interval 3 between the edge of the microstrip short-circuit line 6 and the first metal layer 11 in the third direction Z. The first metal layer 11 is formed with two microstrip stubs 5, which are located between the first interval 7 and the second interval 3, and the LC parallel resonant circuits 15 are arranged at the microstrip stubs 5.

[0060] In this way, by symmetrically arranging the two LC parallel resonant circuits 15, the lightning protection device 100 can further enhance the suppression capability in the dual-frequency band, while ensuring the structural symmetry, reducing the problem of electromagnetic radiation imbalance, and improving the overall electromagnetic compatibility performance.

[0061] In some embodiments, as shown in Figure 3 and Figure 4 , the circuit board further comprises a second metal layer 13 connected to a second surface of the substrate layer 14, the second surface and the first surface being two opposite surfaces of the substrate layer 14 along the thickness direction thereof, and the second metal layer 13 is electrically connected to the first metal layer 11.

[0062] In this way, by adding the second metal layer 13 and electrically connecting it to the first metal layer 11, the ground shielding effect can be enhanced, the external electromagnetic interference can be reduced, and the noise immunity and signal integrity of the lightning protection device 100 can be improved, which is particularly suitable for application scenarios with high requirements on the electromagnetic environment.

[0063] Of course, it can be understood that the circuit board is not limited to arranging the second metal layer 13, and in some embodiments, the circuit board can only have the first metal layer 11 without arranging the second metal layer 13.

[0064] In some embodiments, as shown in Figure 3 and Figure 4 , the substrate layer 14 is formed with a through hole 12 penetrating along the thickness direction thereof, and the second metal layer 13 is electrically connected to the first metal layer 11 through a conductive member arranged in the through hole 12.

[0065] Exemplarily, as shown in Figure 3 , a plurality of through holes 12 are arranged in the region of the substrate layer 14 surrounding the outer periphery of the first pad 1, the second pad 2, the radio frequency line 9, and the microstrip short-circuit line 6, and each through hole 12 is provided with a conductive member.

[0066] In this way, by arranging the through hole 12 and the conductive member, good electrical connection between the first metal layer 11 and the second metal layer 13 is achieved, which not only improves the grounding performance, but also simplifies the manufacturing process and reduces the production cost.

[0067] In some embodiments, the conductive member is a metal plating layer formed on the hole wall of the through hole 12.

[0068] For example, the through hole 12 is provided as a metalized via.

[0069] In this way, the metal plating layer is used as the conductive member, without the need for additional components, and the structure is simple and easy to manufacture, while having good conductivity and mechanical strength, improving the reliability and consistency of the product.

[0070] Of course, it can be understood that the conductive member is not limited to being provided as a metal plating layer, and in some embodiments, the conductive member can be a conductive wire.

[0071] In some embodiments, the first metal layer 11 is made of copper.

[0072] For example, the second metal layer 13 is made of copper.

[0073] In this way, the copper layer made of copper material can effectively conduct signals and reduce resistance, especially in high-frequency circuits, it can also provide complete signal return path, reduce DC wiring, and make signal transmission more stable. Moreover, copper has good thermal conductivity, which can quickly conduct heat from the element to the board surface, avoiding local overheating, which is particularly important for power devices. In addition, the continuous copper layer can shield external interference, reduce internal radiation, and improve the anti-interference ability of the circuit.

[0074] In some embodiments, the length of the microstrip shorting line 6 is determined according to the target frequency and the parameters of the substrate layer 14; the width of the radio frequency line 9 is set to provide a characteristic impedance of about 50Ω; and the radio frequency line 9 has an isolation distance between the two sides of the width direction and the first metal layer 11, which is used to control the impedance of the radio frequency line 9. For example, in a typical implementation, the length of the microstrip shorting line 6 can be 300-400 mil, the width of the radio frequency line 9 can be 15-25 mil, and the distance can be 3-10 mil. As shown in Figure 1 The width of the microstrip shorting line 6 is the size of the microstrip shorting line 6 in the third direction Z. The width of the radio frequency line 9 is the size of the radio frequency line 9 in the second direction Y.

[0075] In this way, by accurately setting the size and distance parameters of each key element, the optimal matching performance of the lightning protection device in the target frequency band is improved, the return loss and insertion loss indicators are improved, and the requirements for radio frequency performance in actual communication systems are met.

[0076] Next, specific examples of some embodiments of the present application will be described with reference to the accompanying drawings.

[0077] As a specific example, as shown in Figure 1 and Figure 2As shown in the figure, a lightning protection device 100 is provided, which comprises a first metal layer 11 and a substrate layer 14 arranged in sequence from top to bottom. The substrate layer 14 is selected to be FR-4 material with a relative dielectric constant of 4.3 and a thickness of 1.6 mm, and the loss tangent is 0.025. The first metal layer 11 is a copper layer. The lightning protection device 100 further comprises a second pad 2, a first pad 1, an LC parallel resonant circuit 15 (formed by a lumped inductor 4 and a lumped capacitor 8 in parallel), a microstrip stub 5, a microstrip short circuit line 6, a radio frequency line 9 and a radio frequency coaxial line 10. The first pad 1 is a rectangular metal structure. The second pad 2 is an octagonal metal pad, and the radio frequency coaxial line 10 comprises an outer metal layer (outer conductor), a dielectric layer and a metal wire core (inner conductor) arranged in sequence from outside to inside. The outer metal layer is welded to the first pad 1, the metal wire core is welded to the second pad 2, the radio frequency line 9 is located at the middle position of the entire first metal layer 11 along the second direction Y, the lumped capacitor 8 and the lumped inductor 4 of the LC parallel resonant circuit 15 together constitute the LC parallel resonant circuit 15, and the LC parallel resonant circuit 15 is symmetrically placed on both sides of the microstrip short circuit line 6 along the width direction. The microstrip stub 5 is used to place the LC parallel resonant circuit 15.

[0078] As a specific example, as shown in Figure 3 and Figure 4 only the difference between this example and the previous example is described, and the difference is that the side of the substrate layer 14 away from the first metal layer 11 is connected with a second metal layer 13, the substrate layer 14 is provided with a plurality of metalized vias which play a shielding role, and the second metal layer 13 is a copper layer.

[0079] Compared with the prior art, the embodiments of the present application have the following outstanding advantages and remarkable effects: 1. Single copper layer or double copper layer can be used, and the cost is low. The embodiments of the present application innovatively propose a lightning protection device for double-frequency single-double panels, which can be applied to single panels and double panels. Compared with existing four-layer panels, six-layer panels and the like, the processing cost of a single copper layer is low and the construction period is shorter.

[0080] 2. Simple structure and convenient processing. The microstrip short circuit line 6 and the LC parallel resonant circuit 15 can achieve excellent double-frequency lightning protection performance in the same copper layer, and a single substrate layer 14 is adopted, which is simple and convenient to process.

[0081] 3. Excellent return loss. The return loss simulation data obtained by using the lightning protection device provided by the embodiments for return loss simulation is as shown in Figure 5As shown in the figure, it can be seen that excellent matching is achieved in both 2.4G and 5G frequency bands, and the required frequency band return loss is below-15dB. The maximum return loss at the resonance point of the two frequency bands reaches-30.08dB. And by precisely designing the resonance of the two frequency bands respectively, there is no other resonance point between the two frequency bands to cause interference to the required frequency band.

[0082] 4. Low insertion loss. S21 data simulation is performed using the lightning protection device provided by the embodiment, and the S21 data simulation curve is as shown in Figure 6 As shown in the figure, it can be seen that the insertion loss of the two frequency bands is below 0.5dB, and the 2.4G frequency band reaches low insertion loss within 0.15dB.

[0083] 5. Frequency band adjustable. The embodiment of the application respectively generates resonance through LC parallel resonant circuit 15 and the principle of microstrip short circuit line 6, so that it can work in 2.4G and 5G frequency bands respectively. Through accurate design of the two frequency bands respectively, adjusting the length equivalent of lumped capacitor 8, lumped inductor 4 and microstrip short circuit line 6, the working frequency can be selected as needed.

[0084] Example one, 2.4G frequency band.

[0085] Referring to the comparison of S11, S21 parameters in Figure 7 and Figure 8 , by changing the value of 0201 package lumped capacitor 8 and lumped inductor 4, the resonance point of 2.4G frequency band can be tuned. When the capacitance value increases from 2pF to 2.2pF, according to the resonance principle, the resonance point moves from 2.458GHz to 2.356GHz.

[0086] Example two, 5G frequency band.

[0087] Referring to the comparison of S11, S21 parameters of L value of microstrip short circuit line 6 in Figure 9 and Figure 10 , by adjusting the length L of microstrip short circuit line 6, the 5G resonance point can be adjusted. When L increases from 360mil to 370mil, the resonance point moves from 5.493GHz to 5.716GHz, while maintaining excellent insertion loss.

[0088] The second aspect of the application provides an electronic device 1000, as shown in Figure 11 The electronic device 1000 includes the lightning protection device 100 provided by the first aspect.

[0089] Exemplarily, the electronic device 1000 comprises the lightning protection device 100, the combiner 400, the 2.4G radio frequency front-end module 501, the 2.4G matching circuit 502, the 5G radio frequency front-end module 601, the 5G matching circuit 602, the antenna 300, and a casing. The casing is grounded, the antenna 300 is located outside the casing, the lightning protection device 100, the combiner 400, the 2.4G radio frequency front-end module 501, the 2.4G matching circuit 502, the 5G radio frequency front-end module 601, and the 5G matching circuit 602 are located inside the casing. The casing is provided with a casing interface 200, an outward end of the casing interface 200 is electrically connected with the antenna 300, and an inward end of the casing interface 200 is electrically connected with the radio frequency coaxial line 10 of the lightning protection device 100. The radio frequency line 9 of the lightning protection device 100 is electrically connected with the combiner 400. The combiner 400 is electrically connected with the 5G radio frequency front-end module 601 through the 5G matching circuit 602, and the combiner 400 is electrically connected with the 2.4G radio frequency front-end module 501 through the 2.4G matching circuit 502. Exemplarily, the combiner 400 is printed on the substrate layer 14.

[0090] In this way, the electronic device 1000 comprising the lightning protection device 100 provided in the first aspect has the multi-frequency lightning protection function, and the cost is reduced and the space occupation is reduced.

[0091] The above embodiments are only used to illustrate the technical solutions of the present application, but not limit the same. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part or all of the technical features. Such modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the specification of the present application. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any manner.

Claims

1. A lightning protection device, characterized in that, include: A substrate layer, wherein a first pad and a second pad are provided on a first surface of the substrate layer, and the first pad and the second pad are spaced apart; A first metal layer is disposed on the first surface, the first metal layer is electrically connected to the first pad, and is spaced apart from the second pad; The radio frequency coaxial cable is disposed on the first surface and includes an inner conductor, a dielectric layer and an outer conductor arranged sequentially from the inside to the outside. The outer conductor is soldered to the first pad and the inner conductor is soldered to the second pad. A lightning protection structure is disposed on the first surface. The lightning protection structure is electrically connected to the second pad and to the first metal layer. The lightning protection structure is configured to allow at least two signals of different frequency bands to be connected to the first metal layer in the event of a lightning strike. An RF line is disposed on the first surface, spaced apart from the first metal layer, and the RF line is electrically connected to the second pad.

2. The lightning protection device according to claim 1, characterized in that, The lightning protection structure includes a microstrip short circuit and a notch filter. One end of the microstrip short circuit is electrically connected to the second pad, and the other end is electrically connected to the first metal layer. The notch filter is connected in parallel with the microstrip short circuit.

3. The lightning protection device according to claim 2, characterized in that, The notch filter includes at least two LC parallel resonant circuits. At least one of the LC parallel resonant circuits is provided on each of the opposite sides of the microstrip short line along its width direction, and each of the LC parallel resonant circuits is connected in parallel with the microstrip short line.

4. The lightning protection device according to claim 3, characterized in that, The thickness direction of the substrate layer is the first direction, the microstrip short line and the radio frequency coaxial line both extend along the second direction and are arranged along the second direction, the inner conductors of the microstrip short line and the radio frequency coaxial line are electrically connected at their closest points through the second pad, the radio frequency line extends along the third direction, and the first direction, the second direction and the third direction are orthogonal to each other.

5. The lightning protection device according to claim 4, characterized in that, The microstrip short circuit and the radio frequency coaxial line are both located at the midpoint of the first surface along the third direction; and / or The radio frequency line is located at the middle position of the first surface along the second direction.

6. The lightning protection device according to any one of claims 1 to 5, characterized in that, The lightning protection device further includes a second metal layer, which is disposed on the second surface of the substrate layer. The second surface and the first surface are two opposing surfaces of the substrate layer along its thickness direction, and the second metal layer is electrically connected to the first metal layer.

7. The lightning protection device according to claim 6, characterized in that, The substrate layer has a through hole extending along its thickness direction, and a conductive element is disposed in the through hole. The second metal layer and the first metal layer are electrically connected through the conductive element.

8. The lightning protection device according to claim 7, characterized in that, The conductive element is a metal plating layer formed on the wall of the through hole.

9. The lightning protection device according to any one of claims 1 to 5, 7 and 8, characterized in that, The first metal layer is made of copper.

10. An electronic device, characterized in that, Includes the lightning protection device as described in any one of claims 1 to 9.

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