Circuit board and electronic equipment

Abstract

The invention discloses a circuit board and electronic equipment, and belongs to the technical field of electronic equipment. The circuit board comprises a substrate, a circuit layer and a first auxiliary part. The base body is provided with a first area and a second area; the circuit layer is arranged on the substrate, the circuit layer comprises a plurality of circuits, the plurality of circuits pass through the second area, the plurality of circuits at least comprise a first circuit group, the first circuit group passes through the first area, and the circuit density in the second area is larger than that in the first area; the first auxiliary part is arranged on the base body, located in the first area and used for adjusting the impedance of the first line group in the first area.

Description

Technical Field

[0001] The present application belongs to the technical field of electronic equipment, and in particular, relates to a circuit board and an electronic equipment. Background Art

[0002] In the related art, the mobile phone's printed circuit board (PCB) also bears the needs of electronic high-frequency and high-speed signal processing, so the performance requirements for the high-frequency and high-speed signal transmission lines on the PCB are getting higher and higher. However, in the design of the PCB board, some transmission lines pass through both the dense line area and the non-dense line area in the same line layer. Due to the large difference in the residual copper rate between the dense line area and the non-dense line area, the transmission line has a characteristic impedance discontinuity problem, which in turn affects the high-speed and high-frequency performance of the circuit board. Summary of the invention

[0003] The present application aims to provide a circuit board and an electronic device, which at least solve one of the problems of poor high-speed and high-frequency performance of the circuit board.

[0004] To this end, a first aspect of the present application provides a circuit board.

[0005] A second aspect of the present application provides an electronic device.

[0006] In view of this, the first aspect of the present application provides a circuit board, the circuit board includes a substrate, a circuit layer and a first auxiliary part. The substrate has a first area and a second area; the circuit layer is arranged on the substrate, the circuit layer includes a plurality of circuits, the plurality of circuits pass through the second area, a first circuit group among the plurality of circuits passes through the first area, and the circuit density in the second area is greater than the circuit density in the first area, wherein the first circuit group is a part of the plurality of circuits; the first auxiliary part is arranged on the substrate, located in the first area, and is used to adjust the impedance of the first circuit group in the first area.

[0007] In this technical solution, the present application discloses a circuit board, which includes a substrate, a circuit layer and a first auxiliary part. Among them, the substrate is the basic material for supporting and insulating circuit elements, the circuit layer is mainly used to realize the electrical connection of various elements in the circuit, and the transmission of high-frequency and high-speed signals, and the first auxiliary part is used to adjust the characteristic impedance in the circuit board. Specifically, the circuit layer is arranged on the substrate, and multiple lines of the circuit layer pass through the second area of ​​the substrate to form a line-dense area; the first line group of multiple lines passes through the first area to form a line-non-dense area, and the line density of the second area is greater than the line density of the first area. A first auxiliary part is also provided in the circuit board, and the first auxiliary part is arranged on the substrate and located in the first area. The characteristic impedance of the first line group in the first area is adjusted by the first auxiliary part, so that the characteristic impedance of the first line group in each area tends to be consistent, thereby improving the transmission line performance of high-frequency and high-speed signals in the circuit board on the basis of realizing the thinness of the circuit board, and improving the high-speed and high-frequency performance of the circuit board.

[0008] The second aspect of the present application provides an electronic device, comprising a circuit board as in any of the above technical solutions. Therefore, the electronic device has all the beneficial effects of the circuit board as in any of the above technical solutions, which will not be described in detail here.

[0009] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0011] Figure 1 is one of the top views of a circuit board according to an embodiment of the present application;

[0012] Figure 2 is a second top view of a circuit board according to an embodiment of the present application;

[0013] Figure 3 is a cross-sectional view of a circuit board according to an embodiment of the present application;

[0014] Figure 4 is a third top view of a circuit board according to an embodiment of the present application;

[0015] Figure 5 is a fourth top view of a circuit board according to an embodiment of the present application;

[0016] Figure 6 is a fifth top view of a circuit board according to an embodiment of the present application;

[0017] Figure 7is a schematic diagram of substrate thickness detection according to an embodiment of the present application;

[0018] Figure 8 is one of the cross-sectional views of a circuit board stripline according to an embodiment of the present application;

[0019] Fig. 9 This is the second cross-sectional view of the circuit board strip line according to the embodiment of the present application.

[0020] Reference numerals:

[0021] 100 circuit board, 110 substrate, 112 first area, 114 second area, 116 third area, 120 circuit layer, 122 circuit, 124 first circuit group, 126 second circuit, 128 first circuit, 130 first auxiliary part, 140 ground copper layer, 150 second auxiliary part, 160 thickness detection module, 162 first conductive part, 164 second conductive part, 166 capacitance detection module, 170 conductive hole, 180 integrated circuit device, 182 solder, 184 discrete device. DETAILED DESCRIPTION

[0022] The embodiments of the present application will be described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as limitations on the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application.

[0023] The term "first" or "second" in the specification and claims of this application may include one or more of the features explicitly or implicitly. In the description of this application, unless otherwise specified, "plurality" means two or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the objects connected before and after are in an "or" relationship.

[0024] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0025] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0026] Combine the following Figures 1 to 9 A circuit board and an electronic device according to embodiments of the present application are described.

[0027] The first aspect of the present application provides a circuit board 100, such as Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the circuit board 100 includes a substrate 110, a circuit layer 120 and a first auxiliary part 130. The substrate 110 has a first area 112 and a second area 114; the circuit layer 120 is arranged on the substrate 110, and the circuit layer 120 includes a plurality of circuits 122, the plurality of circuits 122 pass through the second area 114, a first circuit group 124 of the plurality of circuits 122 passes through the first area 112, and the circuit density in the second area 114 is greater than the circuit density in the first area 112, wherein the first circuit group 124 is a part of the plurality of circuits 122; the first auxiliary part 130 is arranged on the substrate 110, located in the first area 112, and is used to adjust the impedance of the first circuit group 124 in the first area 112.

[0028] In this embodiment, the present application discloses a circuit board 100, which includes a substrate 110, a circuit layer 120 and a first auxiliary part 130. Among them, the substrate 110 is a basic material for supporting and insulating circuit elements, the circuit layer 120 is mainly used to realize the electrical connection of various elements in the circuit, and the transmission of high-frequency and high-speed signals, and the first auxiliary part 130 is used to adjust the characteristic impedance in the circuit board 100. Specifically, the circuit layer 120 is arranged on the substrate 110, and the multiple circuits 122 of the circuit layer 120 pass through the second area 114 of the substrate 110 to form a circuit-intensive area; the first circuit group 124 of the multiple circuits 122 passes through the first area 112 to form a circuit-non-intensive area, and the circuit density of the second area 114 is greater than the circuit density of the first area 112. Among them, the multiple circuits 122 are strip lines, which are transmission lines for high-frequency and high-speed signals. A first auxiliary part 130 is also arranged in the circuit board 100, and the first auxiliary part 130 is arranged on the substrate 110 and located in the first area 112. The characteristic impedance of the first circuit group 124 in the first area 112 is adjusted by the first auxiliary part 130, so that the characteristic impedance of the first circuit group 124 tends to be consistent in each area, thereby improving the transmission line performance of high-frequency and high-speed signals in the circuit board 100 on the basis of achieving the lightweight and thinning of the circuit board 100, thereby improving the high-speed and high-frequency performance of the circuit board 100.

[0029] Among them, Figure 3 As shown, the substrate 110 can be made of glass cloth epoxy resin, ceramic, phenolic resin, solder resist ink, etc., and the circuit layer 120 can be made of metal copper foil, metal silver, metal nickel gold, metal tin, carbon, etc. The circuit board 100 also includes an integrated circuit (IC) device 180 and a discrete device 184. The integrated circuit device 180 is fixed on the circuit board 100 by solder 182.

[0030] In some embodiments of the present application, optionally, Figure 4 and Figure 5 As shown, the circuit board 100 further includes a grounding copper layer 140 , which is disposed on the substrate 110 . The grounding copper layer 140 includes a plurality of first auxiliary portions 130 , which are arranged at intervals.

[0031] In this embodiment, the circuit board 100 also includes a ground copper layer 140, which includes a plurality of first auxiliary parts 130. The plurality of first auxiliary parts 130 are arranged at intervals so that the ground copper layer 140 adjusts the characteristic impedance of the first circuit group 124 through the plurality of first auxiliary parts 130, so that the characteristic impedance of the first circuit group 124 tends to be consistent in each area, thereby improving the transmission line performance of high-frequency and high-speed signals in the circuit board 100 and improving the high-speed and high-frequency performance of the circuit board 100.

[0032] In some embodiments of the present application, optionally, Figure 4 and Figure 5 As shown, the first auxiliary portion 130 is in a block shape, and a plurality of first auxiliary portions 130 are arranged in a grid shape.

[0033] In this embodiment, the first auxiliary part 130 of the ground copper plating layer 140 is block-shaped, and multiple first auxiliary parts 130 are arranged in a grid-like manner around the first circuit group 124, converting the solid ground copper plating layer 140 design into a grid-shaped ground copper plating layer 140 design, reducing the variation of the residual copper rate of the circuit board 100, making the characteristic impedance of the first circuit group 124 tend to be consistent in each area, improving the transmission line performance of high-frequency and high-speed signals in the circuit board 100, and improving the high-speed and high-frequency performance of the circuit board 100.

[0034] In some embodiments of the present application, optionally, Figure 4 and Figure 5 As shown, the first auxiliary portion 130 is in a strip shape and is arranged along the first line group 124 .

[0035] In this embodiment, the first auxiliary portion 130 of the ground copper plating layer 140 is in a strip shape, and the first auxiliary portion 130 is arranged along the periphery of the first circuit group 124. The first auxiliary portion 130 may be one or more. When there are multiple first auxiliary portions 130, they may be arranged along both sides of the first circuit group 124, or along one side of the first circuit group 124. By converting the solid copper plating layer design into a ground copper plating layer 140 design of multiple discrete circuits, the variation of the residual copper rate of the circuit board 100 is reduced, so that the characteristic impedance of the first circuit group 124 tends to be consistent in each area, improving the transmission line performance of high-frequency and high-speed signals in the circuit board 100, and improving the high-speed and high-frequency performance of the circuit board 100.

[0036] Exemplarily, during the PCB lamination process, the resin in the substrate 110 will fill the space where the copper foil is etched away. Therefore, the area with a lower residual copper rate (ratio of copper foil not etched) has a thinner thickness of the corresponding substrate 110 after lamination. The corresponding formula is: ΔH≈kΔS, where ΔH is the thickness change value of the substrate 110 after lamination, ΔS is the residual copper rate change value in a specific area, and k is the proportional coefficient (the proportional coefficient is related to the process of different PCB factories). For example, for a strip line, within a range of 2mm around it, if the residual copper rate change value is 2%, then the corresponding thickness change value of the substrate 110 after lamination is about 3um. Under the condition that other conditions remain unchanged, due to the change in the thickness of the PCB substrate 110, the characteristic impedance of the same transmission line will change suddenly. For example, a 3um change in the thickness of the above-mentioned substrate 110 will produce a characteristic impedance mutation of about 2Ω. In the area where the residual copper rate varies greatly within the impact range of the present application, the residual copper rate is changed within 1% by converting the solid ground copper layer 140 design into a grid-shaped ground copper layer 140 design, or by converting the solid ground copper layer 140 design into a ground copper layer 140 design with multiple discrete lines, thereby reducing the thickness change value of the substrate 110, thereby reducing the change in characteristic impedance, and on the basis of achieving the lightweight circuit board 100, improving the transmission line performance of high-frequency and high-speed signals in the circuit board 100, and improving the high-speed and high-frequency performance of the circuit board 100.

[0037] In some embodiments of the present application, optionally, Figure 6 As shown, the first line group 124 includes a first line 128 , and the first auxiliary portion 130 is arranged along the first line 128 and is an integral structure with the first line 128 .

[0038] In this embodiment, the first auxiliary portion 130 is disposed along the first line 128 and is an integrated structure with the first line 128, so that the first auxiliary portion 130 is a part of the first line 128 to increase the overall width of the first line 128. By increasing the overall width of the first line 128, the characteristic impedance of the first line 128 tends to be consistent in various regions, thereby improving the transmission line performance of high-frequency and high-speed signals in the circuit board 100, and improving the high-speed and high-frequency performance of the circuit board 100.

[0039] Meanwhile, when manufacturing the circuit board 100, the first auxiliary portion 130 and the first circuit 128 can be made into an integrated structure by etching and other processes, which simplifies the structure of the circuit board 100 and simplifies the production process of the circuit board 100, thereby improving production efficiency.

[0040] In some embodiments of the present application, optionally, Figure 6As shown, the sum of the width of the first auxiliary portion 130 and the width of the first line 128 in the first region 112 is the first width (eg Figure 6 The width of the first line 128 in the second region 114 is the second width (eg Figure 6 The second width is smaller than the first width (the width shown by the arrow W2).

[0041] In this embodiment, the first auxiliary portion 130 is set as a part of the first line 128 in the first area 112, so that the line width in the first area 112 is greater than the line width in the second area 114, that is, the first width is greater than the second width. By making the first width in the first area 112 greater than the second width in the second area 114, the characteristic impedance of the first line 128 tends to be consistent in each area, thereby improving the transmission line performance of high-frequency and high-speed signals in the circuit board 100, and improving the high-speed and high-frequency performance of the circuit board 100.

[0042] Exemplarily, in the area where the residual copper rate changes greatly within the impact range, the present application does not change the residual copper rate of the area (due to grounding integrity), but instead widens the line width of the first line 128 so that the characteristic impedance of the first line 128 tends to be consistent in each area, thereby improving the transmission line performance of high-frequency and high-speed signals in the circuit board 100. For example, the line width in the line-dense area remains unchanged, and the line width in the non-line-dense area is widened, so that the characteristic impedance of the first line 128 tends to be consistent in each area, thereby improving the transmission line performance of high-frequency and high-speed signals in the circuit board 100, and improving the high-speed and high-frequency performance of the circuit board 100. Specifically, the line width in the line-dense area is 40um (the line width is limited by routing resources), and the line width in the non-line-dense area is widened to 53um. The thickness of the substrate 110 can also be increased by 3um, so that the characteristic impedance of the first line 128 in the non-line-dense area suddenly changes to 2Ω, and the characteristic impedance of the first line 128 tends to be consistent in each area.

[0043] In some embodiments of the present application, optionally, Figure 6 As shown, the substrate 110 further has a third area 116, and along the extension direction of the first line group 124, the third area 116 is located between the first area 112 and the second area 114; the circuit board 100 further includes a second auxiliary portion 150, and the second auxiliary portion 150 is disposed on the substrate 110 and located in the third area 116; wherein the sum of the width of the second auxiliary portion 150 and the width of the first line 128 in the third area 116 is the third width (such as Figure 6 The third width decreases from one end of the second auxiliary portion 150 close to the first region 112 to one end of the second auxiliary portion 150 close to the second region 114.

[0044] In this embodiment, while increasing the width of the first line 128 in the first area 112, a transition area is set between the first area 112 and the second area 114, that is, the third area 116. A second auxiliary portion 150 is set in the third area 116, and the sum of the width of the second auxiliary portion 150 and the first line 128 in the third area 116 is defined as the third width, and the third width gradually decreases from the end of the second auxiliary portion 150 close to the first area 112 to the end of the second auxiliary portion 150 close to the second area 114. In the circuit board 100, in order to better control the characteristic impedance of signal transmission, a transition area is set between the first area 112 and the second area 114 to avoid problems such as signal reflection, thereby further improving the transmission line performance of high-frequency and high-speed signals in the circuit board 100.

[0045] In some embodiments of the present application, optionally, Figure 7 As shown, the circuit board 100 further includes a thickness detection module 160 . The thickness detection module 160 is disposed on the base 110 and is used to detect the thickness of the circuit board 100 .

[0046] In this embodiment, the circuit board 100 also includes a thickness detection module 160, which is disposed on the substrate 110 and is used to detect the thickness of the circuit board 100, associate the actual detection value with the subsequent matching device specifications and driving strength, and select the most appropriate optimization scheme according to the requirements to improve the corresponding high-speed performance.

[0047] Furthermore, different batches of materials and manufacturing tolerances may lead to differences in the thickness of the finished substrate 110. By designing a PCB substrate 110 finished product thickness detection module 160 in a specific area, the thickness of the circuit board 100 is detected by using the thickness detection module 160, and the detection result is converted into the driving strength of the high-speed signal on the corresponding transmission line to improve the corresponding high-speed performance.

[0048] In some embodiments of the present application, optionally, Figure 7 As shown, the thickness detection module 160 includes a first conductive part 162, a second conductive part 164 and a capacitance detection module 166. The first conductive part 162 is disposed on one side of the substrate 110; the second conductive part 164 is disposed on the other side of the substrate 110; the capacitance detection module 166 is disposed on the substrate 110, and is electrically connected to one of the first conductive part 162 and the second conductive part 164, and can detect the capacitance value between the first conductive part 162 and the second conductive part 164, so as to obtain the thickness of the circuit board 100 according to the capacitance value.

[0049] In this embodiment, the thickness detection module 160 includes a first conductive part 162, a second conductive part 164 and a capacitance detection module 166. The first conductive part 162 and the second conductive part 164 are respectively arranged on both sides of the substrate 110, and are used to measure the thickness of the circuit board 100. The capacitance detection module 166 is arranged on the substrate 110, and is electrically connected to one of the first conductive part 162 and the second conductive part 164 through the capacitance detection module 166, so that a potential difference is generated between the first conductive part 162 and the second conductive part 164. Under the action of the electric field, a capacitance effect is formed between the first conductive part 162 and the second conductive part 164, so that the capacitance detection module 166 obtains the capacitance value, and the thickness of the circuit board 100 can be detected according to the capacitance value. The detection result is converted into the driving strength of the high-speed signal on the corresponding transmission line to improve the corresponding high-speed performance.

[0050] In some embodiments of the present application, optionally, Figure 7 As shown, the circuit board 100 further includes a second circuit 126 and a conductive hole 170. The second circuit 126 is disposed on the substrate 110, and one end of the second circuit 126 is connected to one of the first conductive portion 162 and the second conductive portion 164; the conductive hole 170 is disposed on the substrate 110 and connected to the other end of the second circuit 126; and the pins of the capacitance detection module 166 are inserted into the conductive hole 170.

[0051] In this embodiment, the circuit board 100 further includes a second circuit 126 and a conductive hole 170. The second circuit 126 is disposed on the substrate 110, one end of the second circuit 126 is connected to one of the first conductive portion 162 and the second conductive portion 164, and the other end of the second circuit 126 is connected to the conductive hole 170. The second circuit 126 is used to electrically connect the capacitance detection module 166 to one of the first conductive portion 162 and the second conductive portion 164, so as to generate a potential difference between the first conductive portion 162 and the second conductive portion 164. The conductive hole 170 is disposed on the substrate 110, and the pins of the capacitance detection module 166 are inserted into the conductive hole 170, which facilitates the installation of the capacitance detection module 166, simplifies the assembly process of the circuit board 100, and improves production efficiency.

[0052] In some embodiments of the present application, optionally, Figure 7 As shown, at least one of the first conductive portion 162 and the second conductive portion 164 is located in the circuit layer 120 .

[0053] In this embodiment, when etching the circuit layer 120, the first conductive part 162 and the second conductive part 164 can be etched together, so that the first conductive part 162 and the second conductive part 164 are fixed in the circuit board 100, so that the detection result is more accurate. At the same time, the manufacturing process of the circuit board 100 is simplified and the production efficiency is improved.

[0054] Exemplarily, independent conductive parts of specific specifications are designed in specific areas of the circuit layer 120 above and below the PCB pressed substrate 110, such as a square conductive part of 5mm×5mm, and the conductive part of one layer is connected to the detection circuit port through the second circuit 126 and the conductive hole 170. After the potential difference is added between the overlapping conductive parts of the upper and lower layers after pressing, a capacitance effect will be formed under the action of the electric field. The corresponding capacitance Cr is shown in the formula: Cr=Er A / H1, where Er is the dielectric constant of the PCB substrate 110, A is the area of ​​the conductive part, and H1 is the thickness of the substrate 110 after the PCB is pressed. The dielectric constant Er of the substrate 110 is related to the area of ​​the conductive part (such as Figure 7 The area indicated by the arrow A in the middle is a fixed value, so the corresponding thickness of the substrate 110 (such as Figure 7 After the thickness detection of the substrate 110 of the finished PCB is completed, the actual detection value is associated with the subsequent matching device specifications and driving strength, and the most suitable optimization solution is selected according to the requirements.

[0055] The second aspect of the present application provides an electronic device, comprising a circuit board 100 as in any of the above embodiments. Therefore, the electronic device has all the beneficial effects of the circuit board 100 as in any of the above embodiments, which will not be described in detail here.

[0056] In some embodiments of the present application, optionally, Figure 8 and Fig. 9 As shown, taking the strip line as an example, its characteristic impedance Z0 (unit length) is mainly affected by the following factors, including: line width W, copper thickness T, substrate 110 thickness H, substrate 110 dielectric constant Er, the formula of characteristic impedance Z0 is,

[0057]

[0058] The embodiments of the present application provide a plurality of design schemes for a lightweight PCB board to solve the problem of a sudden change in characteristic impedance of the transmission line caused by a change or inconsistency in thickness of the substrate 110, thereby improving the transmission line performance of high-frequency and high-speed signals of the circuit board 100 on the basis of achieving a lightweight PCB board.

[0059] The implementation mode of the present application can be extended to other mobile terminal circuit boards 100 that require a thin and lightweight PCB board, not only limited to the application scenarios of mobile phones, but also including electronic devices such as tablet computers, car screens and smart watches.

[0060] The embodiments of the present application are also applicable to other types of PCB boards, and are also applicable to scenarios where the performance is affected due to changes in the thickness of the substrate 110 , and are not limited to thin and light PCB boards.

[0061] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0062] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A circuit board, characterized in that: include: a substrate having a first region and a second region; A circuit layer, the circuit layer is arranged on the substrate, the circuit layer includes a plurality of circuits, the plurality of circuits pass through the second area, a first circuit group among the plurality of circuits passes through the first area, and the circuit density in the second area is greater than the circuit density in the first area, wherein the first circuit group is a part of the plurality of circuits; The first auxiliary part is arranged on the substrate and located in the first area, and is used to adjust the impedance of the first line group in the first area.

2. The circuit board according to claim 1, characterized in that: Also includes: A grounding copper layer is provided on the substrate, and the grounding copper layer comprises a plurality of the first auxiliary parts, and the plurality of the first auxiliary parts are arranged at intervals.

3. The circuit board according to claim 2, characterized in that: The first auxiliary portion is block-shaped, and a plurality of the first auxiliary portions are arranged in a grid shape.

4. The circuit board according to claim 2, characterized in that: The first auxiliary portion is in a strip shape and is arranged along the first line group.

5. The circuit board according to claim 1, characterized in that: The first circuit group includes a first circuit, and the first auxiliary portion is arranged along the first circuit and is an integrated structure with the first circuit.

6. The circuit board according to claim 5, characterized in that: The sum of the width of the first auxiliary portion and the width of the first line in the first region is a first width; The width of the first line in the second region is a second width, and the second width is smaller than the first width.

7. The circuit board according to claim 5, characterized in that: The substrate further comprises a third region, and along the extension direction of the first line group, the third region is located between the first region and the second region; The circuit board further includes a second auxiliary portion, which is disposed on the base body and located in the third area; The sum of the width of the second auxiliary portion and the width of the first line in the third region is the third width, and the third width decreases from one end of the second auxiliary portion close to the first region to one end of the second auxiliary portion close to the second region.

8. The circuit board according to any one of claims 1 to 7, characterized in that: Also includes: A thickness detection module is disposed on the substrate and is used to detect the thickness of the circuit board.

9. The circuit board according to claim 8, characterized in that: The thickness detection module comprises: a first conductive portion, the first conductive portion being disposed on one side of the substrate; a second conductive portion, the second conductive portion being disposed on the other side of the substrate; A capacitance detection module is disposed on the substrate and is electrically connected to one of the first conductive part and the second conductive part, and is capable of detecting a capacitance value between the first conductive part and the second conductive part to obtain a thickness of the circuit board based on the capacitance value.

10. The circuit board according to claim 9, characterized in that: Also includes: a second circuit, wherein the second circuit is disposed on the substrate, and one end of the second circuit is connected to one of the first conductive portion and the second conductive portion; A conductive hole, which is arranged on the substrate and connected to the other end of the second circuit; The pins of the capacitance detection module are inserted into the conductive holes.

11. The circuit board according to claim 9, characterized in that: At least one of the first conductive portion and the second conductive portion is located in the circuit layer.

12. An electronic device, characterized in that: Comprising the circuit board as claimed in any one of claims 1 to 11.

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