Circuit board, antenna and electronic equipment
By integrating inductor coils on a functional substrate, the problem of low integration of inductor devices is solved, enabling accurate tuning of inductance values and precise matching of antenna performance, reducing production costs and debugging frequency, and improving production efficiency.
Patent Information
- Application Number
- CN202520250535.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-17
- Publication Date
- 2026-01-20
- Estimated Expiration
- 2035-02-17
AI Technical Summary
In existing technologies, the low integration of inductors and circuit boards leads to parasitic effects introduced by soldering. This makes it difficult to accurately quantify the impact on antenna radiation performance during the design phase, requiring multiple prototyping and debugging processes, which increases manpower and material costs.
By integrating the inductor coil onto the functional substrate, the antenna feed port can be tuned by adjusting the parameters of the inductor coil, avoiding the use of discrete inductor components, improving the matching accuracy between the inductance value and the antenna performance, and simplifying the design process.
This improved the matching accuracy between inductance value and antenna performance, reduced design and debugging costs, decreased manpower and material waste, and increased production efficiency.
Smart Images
Figure CN223816270U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present disclosure relates to the technical field of antennas, and in particular to a circuit board, an antenna and an electronic device. BACKGROUND
[0002] In the process of antenna design, an inductive device needs to be used to tune the feed port of the antenna to reduce the power reflection loss from the radio frequency end to the radiating antenna end, and to achieve good radio frequency signal path performance.
[0003] The inductive device in the related art usually adopts a discrete device, and the inductive device is arranged on the circuit board by means of surface mounting welding. Since the integration of the inductive device and the circuit board is low, the welding of the inductive device also introduces a parasitic effect, and it is difficult to accurately quantify the specific influence of the inductive device on the antenna radiation performance through simulation in the design stage. Therefore, there is often a large frequency deviation between the actual product and the design target, different inductive devices need to be replaced, and multiple trial productions and debugging are required to obtain a relatively ideal radio frequency signal path performance.
[0004] However, the debugging in the related art is usually difficult to achieve optimal matching effect, and multiple trial productions and debugging require high human input and also waste a large amount of materials, resulting in increased production cost. SUMMARY
[0005] To overcome the problems in the related art, the present disclosure provides a circuit board, an antenna and an electronic device.
[0006] According to a first aspect of the present disclosure, a circuit board is provided, comprising a plurality of substrates arranged in a stack, at least one of the plurality of substrates is arranged as a functional substrate, the functional substrate is integrated with an inductive coil, and the inductive coil is used to realize tuning of a feed port of an antenna.
[0007] In a possible implementation, the functional substrate includes at least two functional substrates, and the at least two functional substrates are arranged adjacently.
[0008] The inductive coils on the two adjacent functional substrates are electrically connected through a via hole.
[0009] In a possible implementation, each inductive coil includes a plurality of turns of wire, and a gap is arranged between two adjacent turns of wire.
[0010] In a possible implementation, the gaps between any two adjacent turns of wire are equal; or
[0011] The gaps between any two adjacent turns of wire are not equal; or
[0012] The gap between any two adjacent turns of the winding is equal.
[0013] In a possible implementation, each turn of the winding includes an inner end and an outer end, and the inner ends of the turns of the winding in adjacent layers of the functional substrate are connected.
[0014] In a possible implementation, the outer ends of the inductor coils of the functional substrate in the top layer of the circuit board are connected to a radio frequency signal path; and / or,
[0015] The inner ends of one of the inductor coils in the plurality of layers of the inductor coils are grounded.
[0016] In a possible implementation, the inductor coils are disposed on the functional substrate by printing.
[0017] In a possible implementation, when the current directions of the inductor coils on each of the at least two layers of the functional substrate are the same, the inductance value of the plurality of layers of the inductor coils increases.
[0018] Or,
[0019] When the current directions of the inductor coils in the top layer of the at least two layers of the functional substrate are opposite to the current directions of the inductor coils in other layers of the at least two layers of the functional substrate, the inductance value of the plurality of layers of the inductor coils decreases.
[0020] In a possible implementation, the number of turns of the winding of the inductor coil is positively correlated with the inductance value of the inductor coil.
[0021] And / or,
[0022] The gap between any two adjacent turns of the winding of the inductor coil is negatively correlated with the inductance value of the inductor coil.
[0023] And / or,
[0024] The width of the winding of the inductor coil is negatively correlated with the inductance value of the inductor coil.
[0025] According to a second aspect of the present disclosure, an antenna is provided, including an antenna body and a tuning circuit, the tuning circuit being disposed on the circuit board according to the first aspect of the present disclosure, and the tuning circuit including the inductor coils of the circuit board.
[0026] According to a third aspect of the present disclosure, an electronic device is provided, including the antenna according to the second aspect of the present disclosure.
[0027] The technical scheme provided by the embodiment of the present disclosure can have the following beneficial effects: the present disclosure integrates the inductor coil for tuning the feed port of the antenna on the functional substrate, and more accurate inductance values can be obtained by adjusting the parameters of the inductor coil integrated on the circuit board, without purchasing separate inductor devices with fixed inductance values, which not only improves the performance matching accuracy of the inductance value and the antenna, but also reduces the research and development cost of debugging and simulation of the inductor coil and the antenna in the design stage, without the need for multiple trial production and debugging before production, avoiding the waste of labor cost and material cost, and improving the production efficiency.
[0028] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present disclosure. BRIEF DESCRIPTION OF DRAWINGS
[0029] The accompanying drawings, which are incorporated into and form part of the specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the disclosure.
[0030] Figure 1 is a structural schematic diagram of an electronic device in the related art.
[0031] Figure 2 is a structural schematic diagram of an electronic device according to an exemplary embodiment.
[0032] Figure 3 is a structural schematic diagram of an inductor coil according to an exemplary embodiment. DETAILED DESCRIPTION
[0033] The exemplary embodiments will be described in detail herein with reference to the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present disclosure. Instead, they are merely examples of apparatuses and methods consistent with some aspects of the present disclosure as detailed in the appended claims.
[0034] In the antenna design process, inductor devices, capacitor devices, etc. are needed to tune the feed port of the antenna to reduce the power reflection loss from the radio frequency end to the radiating antenna end, and to achieve good radio frequency signal path performance. For example, the inductor device is usually integrated on the circuit board, and the inductance value of the inductor device is usually fixed. In order to achieve the desired inductance value, the inductor device needs to be replaced, which not only increases the cost of the antenna, but also increases the design difficulty. Figure 1As shown, in the related art, the inductive device 201' and the capacitive device (not shown in the figure) of the tuning circuit 32' are usually discrete devices, and the inductive device 201' is arranged on the circuit board 10' by means of surface mount welding. Since the integration of the inductive device 201' and the circuit board 10' is low, the welding of the inductive device 201' will also cause the introduction of a parasitic effect, and it is difficult to accurately quantify the specific influence of the inductive device 201' on the radiation performance of the antenna 30' through simulation in the design stage. Therefore, there is often a large frequency deviation between the actual product and the design target, and different inductive devices and capacitive devices need to be replaced for multiple trial production and debugging to obtain a relatively ideal radio frequency signal channel performance.
[0035] However, the debugging in the related art is usually difficult to achieve optimal matching effect, and the human input is high for multiple trial production and debugging, and a large amount of materials is also wasted, resulting in increased production cost.
[0036] To solve the above technical problems, the present disclosure provides a circuit board, an antenna and an electronic device. By integrating an inductive coil for tuning a feed port of an antenna on a functional substrate, a more accurate inductance value can be obtained by adjusting the parameters of the inductive coil integrated on the circuit board. Without purchasing discrete inductive devices with fixed inductance values, the inductance value and the performance matching accuracy of the antenna can be improved, the research and development cost of debugging and simulation of the inductive coil and the antenna in the design stage is reduced, multiple trial production and debugging before production are not required, the waste of human cost and material cost is avoided, and the production efficiency is improved.
[0037] According to an exemplary embodiment, as shown in Figures 2-3 As shown, the present embodiment provides a circuit board 10, which can be a PCB (Printed Circuit Board). It can be understood by those skilled in the art that the technical solutions of the present embodiment can also be applied to other types of circuit boards 10, such as FPC (Flexible Printed Circuit Board). The present embodiment does not make special limitations on this. In an example, the circuit board 10 is a mainboard of an electronic device, and the circuit board 10 is electrically connected with an antenna 30 of the electronic device to realize feeding and tuning of the antenna 30. The antenna 30 can be a middle frame antenna, for example. In another example, the circuit board 10 can be a subboard, and the circuit board 10 as a subboard can be electrically connected with a mainboard (not shown in the figure) of the electronic device and the antenna 30 of the electronic device respectively to electrically connect the antenna 30 and the mainboard. The present embodiment does not make too many limitations on this, and those skilled in the art can set it according to actual needs.
[0038] The circuit board 10 comprises a plurality of substrates arranged in a multilayer stack, at least one of the plurality of substrates is arranged as a functional substrate 11. In one example, the number of functional substrates 11 is one layer; in another example, the number of functional substrates 11 is multiple layers. Among them, the functional substrate 11 can be arranged at the top layer, the bottom layer or the middle layer of the multilayer substrate, and the present embodiment does not make too many limitations thereon, which can be selected by those skilled in the art according to the production and design needs. When selecting the number of functional substrates 11, the design of the inductor coil 20 required in the antenna design process needs to be considered, and then the number of functional substrates 11 is determined.
[0039] The inductor coil 20 is integrated on the functional substrate 11, and the inductor coil 20 is used to realize the tuning of the feed port 31 of the antenna 30. For the tuning process of the antenna 30, in addition to inductive tuning, capacitive tuning is also involved. The present application mainly describes the scheme of integrating the inductor coil 20 on the PCB board. For the capacitive tuning design, a separate capacitor device can be used, or a capacitor device integrated on the PCB board can be used. Here, no more details are given.
[0040] Among them, the inductance value of the inductor coil 20 can be adjusted by adjusting the total length, width, number of turns, number of layers, current direction of each layer of the inductor coil 20, gap between each turn, and other parameters, so as to realize the tuning effect of the antenna 30. The influence of each parameter of the inductor coil 20 on the inductance value will be described in detail later, and no more details are given here. In the present embodiment, the inductor coil 20 can be set according to the design needs of the tuning circuit, thereby improving the tuning accuracy. Since no separate inductor device needs to be welded, the additional radio frequency loss caused by welding is also avoided, and the overall performance of the antenna can be improved. In addition, since the inductor coil 20 is highly integrated on the circuit board 10, the inductance value of the inductor coil 20 can be reasonably designed according to the design needs of the antenna 30 tuning and the required inductance value. Therefore, the influence of the electromagnetic effect of the inductor coil 20 itself on the antenna 30 is more easily and accurately reflected during the simulation simulation in the antenna design stage, and multiple physical debugging is not required, thereby simplifying the design process.
[0041] In the embodiments of the present disclosure, a low-cost and high-integration circuit board is provided for tuning and matching with an antenna. Since the matching circuit is composed of a PCB board-level inductor and a discrete capacitor and a capacitor, in the simulation stage of the antenna, the PCB board-level inductor and the antenna radiator are optimized together to achieve the best matching performance with any inductance value, overcome the discontinuous shortcomings of the discrete inductor, and optimize the inductor coil trace shape to reduce the influence on the antenna radiation performance. At the same time, the PCB board-level inductor has the characteristics of low cost and high integration, improves the production reliability, saves the debugging time, and saves the welding process and material procurement cost.
[0042] In some embodiments, the circuit board 10 includes at least two functional substrates 11. As shown, vias 111 are arranged on the functional substrates 11, and the at least two functional substrates 11 are arranged adjacently, and the inductor coils 20 on the adjacent two functional substrates 11 are connected through the vias 111 to realize the electrical connection between the inductor coils 20 on the adjacent two functional substrates 11. Figure 3
[0043] In some embodiments, each inductor coil 20 includes a plurality of turns of wire 21. Adjacent two turns of wire 21 are arranged with a gap 211, and the gaps 211 between the turns of wire 21 can be equal or unequal.
[0044] In one example, the gaps 211 between any adjacent two turns of wire 21 are equal, so that the inductance generated by the inductor coil 20 is relatively uniform, and it is also convenient to calculate the inductance value.
[0045] In another example, the gaps 211 between any adjacent two turns of wire 21 are unequal. For example, the gaps 211 can uniformly decrease along the direction from the inside to the outside of the inductor coil 20, or uniformly increase along the direction from the inside to the outside of the inductor coil 20, or change non-uniformly along the direction from the inside to the outside of the inductor coil 20.
[0046] In yet another example, the gaps 211 between any adjacent two turns of wire 21 are partially equal. For example, the gaps 211 between part of the adjacent two turns of wire 21 are equal, and are all a first gap, and the remaining gaps 211 are all unequal to the first gap. For another example, the gaps 211 between part of the adjacent two turns of wire 21 are equal, and are all a first gap, and the remaining gaps 211 are all a second gap, and the first gap is unequal to the second gap. Of course, it can be understood that a person skilled in the art can also set the gaps 211 between any adjacent two turns of wire 21 to be partially equal and partially unequal according to actual needs, and the embodiments of the present disclosure do not specially limit the gaps 211 between the turns of wire 21 in the inductor coil 20, and a person skilled in the art can set them according to design needs and processing needs.
[0047] In some embodiments, each winding 21 includes an inner end 212 and an outer end 213. As shown, the inner end 212 is the end of the winding 21 closer to the geometric center of the inductor coil 20, and the outer end 213 is the end of the winding 21 closer to the edge of the inductor coil 20. The inner ends 212 of two adjacent functional substrates 11 are connected, and the inner end 212 is usually taken as the starting end and the outer end 213 is usually taken as the ending end when describing the direction of the winding 21. Figure 3
[0048] In some embodiments, one end of the inductor coil 20 is connected to the radio frequency signal path of the antenna 30, and the other end is grounded. Specifically, as shown, the outer end 213 of the inductor coil 20 of the functional substrate 11 located at the topmost layer of the circuit board 10 is connected to the radio frequency signal path (not shown in the figure); and / or, the inner end 212 of one of the inductor coils 20 in the multi-layer inductor coil 20 is grounded. Figures 2-3
[0049] In one example, the outer end 213 of the inductor coil 20 of the functional substrate 11 located at the topmost layer of the circuit board 10 is connected to the radio frequency signal path, so as to tune the feed port 31 of the antenna 30 to improve the radio frequency performance of the antenna 30.
[0050] In another example, the inner end 212 of one of the inductor coils 20 in the multi-layer inductor coil 20 is grounded. The inner end 212 of the inductor coil 20 can be connected to the ground port (not shown in the figure) of the antenna 30, the inner end 212 can also be connected to the ground end 12 on the mainboard of the electronic device, and the inner end 212 can also be directly connected to the middle frame 40. When the user holds the electronic device, the current can flow through the user's hand and flow to the ground to achieve grounding. By grounding one of the inductor coils 20 in the multi-layer inductor coil 20, the influence of parasitic parameters caused by other components can be reduced, and more accurate inductance can be achieved.
[0051] In yet another example, the outer end 213 of the inductor coil 20 of the functional substrate 11 located at the topmost layer of the circuit board 10 is connected to the radio frequency signal path, and the inner end 212 of one of the inductor coils 20 in the multi-layer inductor coil 20 is grounded. The inductor coil 20 is connected to the radio frequency signal path and grounded at the same time, which can more accurately control the inductance characteristics, thereby achieving precise tuning of the antenna and improving the performance of the antenna.
[0052] In some embodiments, the overall inductance value of the inductor coil 20 can be adjusted by changing the current direction of the inductor coil 20 of part of the functional substrate 11.
[0053] In one example, the current directions of the inductor coils 20 in the multi-layer functional substrate 11 are the same. When the current directions of the inductor coils 20 on each of the at least two layers of the functional substrate 11 are the same, the inductance value of the multi-layer inductor coil 20 increases. By setting the current directions of the inductor coils 20 on each of the at least two layers of the functional substrate 11 to be the same, the inductance of the inductor coil 20 can be increased, and a larger inductance value required can be obtained.
[0054] In another example, when the current direction of the inductor coil 20 on the top layer of the at least two layers of the functional substrate 11 is opposite to the current direction of the inductor coil 20 on the other layer of the at least two layers of the functional substrate 11, the inductance value of the multi-layer inductor coil 20 decreases. By setting at least one of the layers other than the top layer of the functional substrate 11 to be opposite to the current direction of the inductor coil 20 on the top layer, the inductance of the inductor coil 20 can be decreased, and a smaller inductance value required can be obtained.
[0055] In some embodiments, the number of turns of the winding 21 of the inductor coil 20 is positively correlated with the inductance value of the inductor coil 20. In a single-layer inductor coil 20, the more turns of the winding 21, the greater the inductance value of the inductor coil 20, and vice versa.
[0056] In some embodiments, the length of the winding 21 of the inductor coil 20 is positively correlated with the inductance value of the inductor coil 20. In a single-layer inductor coil 20, the longer the length of the winding 21, the greater the inductance value of the inductor coil 20, and vice versa.
[0057] In some embodiments, the size of the gap 211 between two adjacent turns of the winding 21 of the inductor coil 20 is negatively correlated with the inductance value of the inductor coil 20. That is, the smaller the gap 211 between two adjacent turns of the winding 21, the greater the inductance value of the inductor coil 20 as a whole; the greater the gap 211 between two adjacent turns of the winding 21, the smaller the inductance value of the inductor coil 20 as a whole. The gaps 211 between any two adjacent turns of the winding 21 can be equal or unequal, and the embodiments of the present disclosure do not have special limitations on the gaps 211 between the turns of the winding 21 in the inductor coil 20, and a person skilled in the art can set them according to actual needs.
[0058] In some embodiments, the width of the inductor winding is negatively correlated with the inductance value of the inductor. The width of the winding 21 refers to the diameter of a single turn of the winding 21, that is, the maximum length of the cross-sectional shape of the winding 21 in the direction perpendicular to the thickness of the winding 21. For example, when the cross-section of the winding 21 is circular, it is the diameter of the circle; when the cross-section of the winding 21 is rectangular, it is the length or width of the rectangle. Generally, the larger the width of the winding 21, the smaller the inductance value of the inductor 20, and vice versa. The width of the winding 21 at different positions can be equal or unequal, and those skilled in the art can set it as needed. This disclosure does not impose excessive limitations on this aspect.
[0059] Therefore, when the setting area of the inductor coil 20 is fixed, the inductance value of the inductor coil 20 can be increased by one or more of the following methods: increasing the number of turns of the winding 21, increasing the length of the winding 21, decreasing the width of the winding 21, and decreasing the gap 211 between two adjacent turns of the winding 21. Those skilled in the art can set the winding 21 according to actual needs to adjust the inductance value of the inductor coil 20. The embodiments of this disclosure do not impose too many restrictions on the specific setting method of the winding 21.
[0060] This disclosure uses an IFA (Inverted-F) antenna (30) as an example to describe the structure of the inductor coil 20 in detail. IFA antennas are commonly used in mobile communication devices and wireless communication modules. They have a compact structure and a wide bandwidth, and are typically made of metal sheets or conductive materials, resembling an inverted letter F. The design of IFA antennas allows them to operate on multiple frequency bands and achieve both radiation and reception functions, meeting the requirements of miniaturization, high-frequency bandwidth, and good performance. They are widely used in communication devices. Of course, it is understood that the technical solutions of this disclosure can also be applied to other types of antennas, and this disclosure does not impose any special limitations on the specific type of antenna 30.
[0061] In one example, the inductor 20 is positioned within the wiring area S. For example... Figure 3 As shown, the wiring area S is a square area with a side length of 1mm. Considering the compact design of the circuit board 10, the area occupied by the inductor coil 20 cannot be too large. Placing the inductor coil 20 within the square wiring area S with a side length of 1mm can minimize the space occupied by the inductor coil 20 and improve the structural compactness while meeting the design requirements for the inductance value. At the same time, this design size can also avoid structural interference with other structures near the antenna 30 to a certain extent, reserving more design and installation space for other structural designs.
[0062] Wherein, the gap between the adjacent two turns of winding 21 is equal, and each position of winding 21 has equal width, and each position of winding 21 has equal width. In the embodiment of the present disclosure, a square region with a side length of 1mm can be divided into 20*20 small squares (not shown in the figure), and each small square has a side length of 0.05mm, so as to facilitate the wiring of the inductor coil 20, wherein W1 and W2 are both 0.05mm, that is, the gap between the adjacent two turns of winding 21 and the width of winding 21 are both the side length of a small square. Of course, it can be understood that W1 and W2 can also be unequal as shown in Figure 3 The present embodiment does not make too many limitations on this, and those skilled in the art can set it according to actual needs.
[0063] In some embodiments, the inductor coil 20 is provided on the functional substrate by printing. Since the circuit board 10 is a printed circuit board, the printing of the inductor coil 20 can be directly integrated into the production process of the printed circuit board, which is beneficial to batch production and can also reduce material costs. When printing the inductor coil 20, copper or other conductive materials can be plated on the surface of the functional substrate 11, and the shape of the inductor coil 20 can be etched out. The surface of the functional substrate 11 can also be slotted, and the inductor coil 20 can be formed by filling conductive materials in the slot. The shape of the inductor coil 20 can also be directly deposited on the surface of the functional substrate 11, and the present disclosure does not make too many limitations on this.
[0064] Of course, it can be understood that the inductor coil 20 can also be formed by directly winding wires and other ways, and the present embodiment does not make too many limitations on the forming method of the inductor coil 20, and those skilled in the art can select according to actual needs.
[0065] According to an exemplary embodiment, as shown in Figures 2-3 The present embodiment provides an antenna 30, which can be a middle frame antenna for example, for realizing communication. The antenna 30 includes an antenna body 301 (i.e. antenna branch) and a tuning circuit (not shown in the figure), and the tuning circuit 32 includes the inductor coil 20 of the circuit board 10 as described in the above embodiment. The circuit board 10 includes a plurality of laminated substrates, at least one of the plurality of substrates is provided as a functional substrate 11, and the inductor coil 20 is integrated on the functional substrate 11, and the inductor coil 20 is used for realizing the tuning of the feed port 31 of the antenna 30.
[0066] According to an exemplary embodiment, as shown in Figures 2-3As shown, the electronic device according to the embodiments of the present disclosure can be a mobile terminal, a tablet computer, a notebook computer, a smart bracelet, or the like electronic device having a communication function. The electronic device comprises the antenna 30 as described in the above embodiments, and the tuning circuit of the antenna 30 comprises the inductor coil 20 of the circuit board 10 as described in the above embodiments. By integrating the inductor coil 20 on the functional substrate 11 to tune the feed port 31 of the antenna 30, the tuning accuracy and the efficiency of the antenna 30 can be improved, and meanwhile, the tuning effect of the inductor coil 20 and the performance of the antenna 30 can be simulated in the design stage, so that the production efficiency can be improved without the need of multiple trial production and debugging before the production, and the waste of labor cost and material cost can be avoided.
[0067] Other embodiments of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the embodiments disclosed herein. The present disclosure is intended to cover any variations, uses or adaptations of the present disclosure following, in general, the principles of the present disclosure and including such
[0068] It should be understood that the present disclosure is not limited to the precise construction that has been described above and shown in the accompanying drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope of the present disclosure. The scope of the present disclosure is limited only by the appended claims.
Claims
1. A circuit board, characterized by, The substrate includes a plurality of layers, at least one of the plurality of layers is a functional substrate, and the functional substrate is integrated with an inductor coil for tuning a feed port of an antenna.
2. The circuit board of claim 1, wherein The functional substrate includes at least two layers, and the at least two layers are arranged adjacently. The inductor coils on the two adjacent functional substrates are electrically connected through a via.
3. The circuit board of claim 2, wherein, Each of the inductor coils includes a plurality of turns, and a gap is arranged between any two adjacent turns.
4. The circuit board of claim 3, wherein The gaps between any two adjacent turns are equal; or The gaps between any two adjacent turns are not equal; or The gaps between any two adjacent turns are partially equal.
5. The circuit board of claim 3, wherein Each of the turns includes an inner end and an outer end, and the inner ends of the turns between the two adjacent functional substrates are connected.
6. The circuit board of claim 5, wherein, The outer end of the inductor coil of the functional substrate on the top layer of the circuit board is connected to a radio frequency signal path; and / or The inner end of one of the inductor coils is grounded.
7. The circuit board of claim 5, wherein The inductor coil is arranged on the functional substrate by printing.
8. The circuit board of claim 2, wherein, When the current directions of the inductor coils on each of the at least two functional substrates are the same, the inductance of the inductor coils increases; or When the current direction of the inductor coil on the top layer of the at least two functional substrates is opposite to the current direction of the inductor coil on the other layer of the at least two functional substrates, the inductance of the inductor coils decreases. The number of turns of the inductor coil is positively correlated with the inductance of the inductor coil; and / or 9. The circuit board of claim 2, wherein, The size of the gap between any two adjacent turns of the inductor coil is negatively correlated with the inductance of the inductor coil; and / or The width of the turns of the inductor coil is negatively correlated with the inductance of the inductor coil. An antenna includes an antenna body and a tuning circuit, the tuning circuit is arranged on the circuit board according to any one of claims 1 to 9, and the tuning circuit includes the inductor coil of the circuit board. The antenna includes the antenna according to claim 10. 10. An antenna, characterized by 11. An electronic device, comprising: