Printed Circuit Board and Electronic Device

Abstract

The present application provides a printed circuit board and an electronic device. The printed circuit board includes a plurality of core boards spaced apart along a first direction, and a prepreg is disposed between every two adjacent core boards. The prepreg is used to fix the two adjacent core boards thereto. Among the plurality of core boards, at least one core board is provided with at least one open area, a filling area is disposed in the open area, a plurality of filling sheets are disposed in the filling area, a gas guiding gap is formed between adjacent filling sheets, and the prepreg is at least partially disposed in the gas guiding gap. The present application can solve the problems that when the prepreg is filled in the open area of the core board in the printed circuit board, air bubbles are easily formed or glue shortage occurs.

Description

Technical Field

[0001] This application relates to the field of electronic devices, and particularly to printed circuit boards and electronic devices. Background Art

[0002] A printed circuit board is an important electronic component that can replace complex wiring to achieve electrical connections between various components in a circuit. The application of printed circuit boards not only simplifies the assembly and soldering work of electronic devices, reduces the wiring workload in the traditional method, and greatly reduces the labor intensity of workers; but also reduces the overall volume of the machine, lowers the equipment cost, and improves the quality and reliability of electronic devices.

[0003] Common multi-layer printed circuit boards are usually formed by laminating multiple core boards, and a prepreg is also provided between adjacent core boards to fix the adjacent core boards through the prepreg. Some of the core boards are provided with open areas. Since the open areas are usually large in area, when using the prepreg to fix adjacent core boards and part of the prepreg fills the open areas of the core boards, it is easy to form bubbles or lack of glue, etc., affecting the structural stability of the printed circuit board. Summary of the Invention

[0004] Embodiments of this application provide a printed circuit board and an electronic device to solve the problem that when part of the prepreg fills the open area of the core board in the printed circuit board, it is easy to form bubbles or lack of glue.

[0005] On the one hand, embodiments of this application provide a printed circuit board, including a plurality of core boards arranged at intervals along a first direction, and a prepreg is provided between every two adjacent core boards, and the prepreg is used to fix the two adjacent core boards thereto;

[0006] Among the plurality of core boards, at least one core board is provided with at least one open area, a filling area is provided in the open area, a plurality of filling sheets are provided in the filling area, a gas guiding gap is formed between adjacent filling sheets, and the prepreg is at least partially provided in the gas guiding gap.

[0007] By adopting the above technical solution, when the plurality of core boards are arranged at intervals and the adjacent core boards are fixed by using the prepreg, the prepreg is located between the adjacent core boards; and the filling area is provided in the open area, the prepreg is provided in the gas guiding gap between adjacent filling sheets, and the adjacent core boards are fixed, so that there is no need to directly fill in the open area, thereby reducing the possibility of bubbles or lack of glue.

[0008] It is further set that, taking the plane where the filling area is located as a cross-section, all the gas guiding gaps are provided with the same width.

[0009] Further configured such that, taking the plane where the filling area is located as a cross-section, each of the filling sheets is in the shape of a regular hexagon or a rectangle.

[0010] Further configured such that the filling sheet is in the shape of a regular hexagon, and the side length of the filling sheet is greater than or equal to 1.2 mm and less than or equal to 1.8 mm; in the first direction, the thickness of the filling sheet is less than or equal to 2OZ; the width of the air guiding gap is greater than or equal to 0.24 mm and less than or equal to 0.36 mm.

[0011] Further configured such that the filling sheet is in the shape of a rectangle, and the length of the filling sheet is greater than or equal to 1.6 mm and less than or equal to 2.4 mm, the width of the filling sheet is greater than or equal to 0.4 mm and less than or equal to 0.6 mm; the width of the air guiding gap is greater than or equal to 0.4 mm and less than or equal to 0.6 mm.

[0012] Further configured such that the core board extends in the second direction, and a preset angle is formed between the length direction of the filling sheet and the second direction, and the preset angle is greater than or equal to 60° and less than or equal to 80°.

[0013] Further configured such that an air guiding area is further provided in the empty area, the air guiding area is arranged around the outside of the filling area, and the air guiding area is communicated with the air guiding gap.

[0014] Further configured such that one or more of signal lines, independent holes, and marking center points are provided in the empty area;

[0015] The distance between the signal line and the filling area, and the distance between the independent hole and the filling area are both greater than 105 mil; the distance between the marking center point and the filling area is greater than 3 mm.

[0016] Further configured such that in the first direction, empty areas are provided on adjacent core boards, and the filling areas on adjacent core boards are arranged oppositely.

[0017] On the other hand, an embodiment of the present application further provides an electronic device, including the above-mentioned printed circuit board. By using the printed circuit board according to the above technical solution, in the empty area of the core board of the printed circuit board, the prepreg is filled in the air guiding gap between adjacent filling sheets and fixes adjacent core boards, so that it is not necessary to directly fill in the empty area, thereby reducing the possibility of bubbles or lack of glue. Description of the Drawings

[0018] The drawings here are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0019] Figure 1A cross-sectional view of a printed circuit board when a filling area is set in an open area provided by an embodiment of the present application;

[0020] Figure 2 A cross-sectional view of a printed circuit board when a filling area is set in an open area provided by an embodiment of the present application;

[0021] Figure 3 A schematic structural diagram of a core board with a filling piece being a regular hexagon provided by an embodiment of the present application;

[0022] Figure 4 A schematic structural diagram of a core board with a filling piece being a rectangle provided by an embodiment of the present application;

[0023] Figure 5 A schematic structural diagram within an open area on a core board provided by an embodiment of the present application.

[0024] Description of reference numerals:

[0025] 1. Core board; 11. Functional area; 12. Open area; 121. Filling area; 1211. Filling piece; 122. Air guiding gap; 123. Air guiding area; 124. Signal line; 125. Independent hole; 126. Marking center point; 13. Base material; 2. Prepreg.

[0026] Through the above-mentioned drawings, specific embodiments of the present application have been shown, and there will be more detailed descriptions hereinafter. These drawings and textual descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. Detailed embodiments

[0027] As described in the background art, currently common multi-layer printed circuit boards are usually formed by laminating multiple core boards, and adjacent core boards are fixed by prepregs. An open area is usually provided on the core board. When using prepregs to fix adjacent core boards, since the open area is usually large in area, the prepreg in a molten state is located between adjacent core boards and fills the open area of the core board, which is likely to form bubbles or lack glue, thus affecting the structural stability of the printed circuit board and further affecting the normal use of the printed circuit board.

[0028] Therefore, to solve the above technical problems, the present application provides a printed circuit board and an electronic device. By setting a filling area in the open area of the core board and arranging a plurality of filling pieces in the filling area, an air guiding gap is formed by adjacent filling pieces, thereby reducing the area of the open area; when using prepregs to fix adjacent core boards, the prepreg in a molten state can fill in the air guiding gap, thereby fixing the adjacent core boards, without directly filling in the large-area open area, and thus reducing the possibility of bubbles or lack of glue.

[0029] Exemplary embodiments will be described in detail herein, and examples thereof are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0030] The technical solution of the present application and how the technical solution of the present application solves the above technical problems will be described in detail below with specific embodiments. These several specific embodiments below can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below with reference to the accompanying drawings.

[0031] Referring to Figures 1-5 , an embodiment of the present application provides a printed circuit board, including a plurality of core boards 1 arranged at intervals along a first direction. A prepreg 2 is disposed between every two adjacent core boards 1, and the prepreg 2 is used to fix the two adjacent core boards 1 thereto. And among the plurality of core boards 1, at least one core board 1 is provided with at least one open area 12. A filling area 121 is disposed in the open area 12, and a plurality of filling sheets 1211 are disposed in the filling area 121. An air guiding gap 122 is formed between adjacent filling sheets 1211. The prepreg 2 is at least partially disposed in the air guiding gap 122, so that the core board 1 having the open area 12 can be fixed to the adjacent core board 1.

[0032] The core board 1 is usually formed by laying a copper sheet on a base material 13 and then removing some of the copper sheets on the base material 13 using an etching solution, thereby forming a functional area 11 and an open area 12 of the core board 1. The functional area 11 is the area where wiring is performed on the core board 1, and the open area 12 is the area on the core board 1 where no wiring or other operations are performed. In the embodiment of the present application, the open area 12 generally refers to a circular area with a diameter greater than or equal to 2 inches, or an irregular graphic area with a side length greater than or equal to 5 inches on one side.

[0033] It is worth mentioning that when the adjacent core boards 1 are fixed using the prepreg 2 in a molten state, when the prepreg 2 contacts the base material 13 of the core board 1, it can adhere to the base material 13; while when the prepreg 2 contacts the copper sheet on the core board 1, the prepreg 2 will not adhere to the copper sheet.

[0034] By adopting the above technical solution, when manufacturing a printed circuit board, multiple core boards 1 are stacked, then the prepreg 2 is placed between two adjacent core boards 1, and then the prepreg 2 is heated to make the prepreg 2 in a molten state. Then, the multiple core boards 1 are pressed together, so that the molten prepreg 2 can fill the air guide gap 122, and the gas in the air guide gap 122 can be discharged through the air guide gap 122, thereby fixing the adjacent core boards 1 without directly filling the large open area 12, and further reducing the possibility of bubbles or lack of glue.

[0035] It should be noted that in the embodiments of the present application, the open area 12 may or may not be provided on the core board 1, and the filling area 121 may be provided in some of the open areas 12. While it is not suitable to set the filling area 121 in some of the open areas 12. For example, in the first direction, if the same area of all the core boards 1 is the open area 12, it is not suitable to set the filling area 121 in this open area 12; or on the core board 1, the open area 12 should not be set in the areas vertically projected by the solder mask opening area and the signal line 124; or in the design document, there are other open areas 12 where the filling area 121 is not allowed to be set, then the filling area 121 should not be set in this open area 12.

[0036] It is easy to understand that in the embodiments of the present application, for example, the filling sheet 1211 can be made of a metal sheet such as a copper sheet, or the filling sheet 1211 can also be made of other materials, and the embodiments of the present application do not make further limitations on this.

[0037] Refer to Figure 3 and Figure 4 , in the embodiments of the present application, the open area 12 is also provided with an air guide area 123. The air guide area 123 is arranged around the outside of the filling area 121. The air guide gap 122 is communicated with the air guide area 123, and in the air guide area 123, the base material 13 of the core board 1 is exposed, so as to be able to contact the molten prepreg 2. When the multiple core boards 1 are pressed together, the molten prepreg 2 can enter the air guide gap 122, so that the gas in the air guide gap 122 can be discharged through the air guide gap 122 and discharged to the air guide area 123, and finally discharged from the air guide area 123, so that the molten prepreg 2 can fill the air guide gap 122, and further fix the adjacent core boards 1.

[0038] When the molten prepreg 2 fills the air guide gap 122 and the air guide area 123, it is easy to understand that a part of the prepreg 2 contacts the side surface of the filling sheet 1211 along the first direction, and another part of the prepreg 2 contacts the base material 13 of the core board 1, thereby fixing the adjacent core boards 1.

[0039] When fixing adjacent core boards 1 with prepreg 2, since prepreg 2 needs to bond with the substrate 13 of adjacent core boards 1, when the two void areas 12 on the two core boards 1 are arranged opposite to each other, it will cause prepreg 2 to need to fill the two void areas 12 simultaneously. As a result, when prepreg 2 is filled into the two void areas 12, it is more likely to have bubbles or lack of glue and other situations.

[0040] Referring to Figures 1-5 , in the embodiment of the present application, exemplarily, in the first direction, void areas 12 are provided on both adjacent core boards 1, and the filling areas 121 on the adjacent two core boards 1 are arranged opposite to each other. By adopting the above technical solution, when fixing adjacent core boards 1 with prepreg 2, the void areas 12 on the adjacent two core boards 1 are arranged opposite to each other, and the filling areas 121 are arranged within the void areas 12, so that when prepreg 2 is filled in the void areas 12, it can be filled in the air guiding gaps 122 and the air guiding areas 123, thereby enabling prepreg 2 not to need to fill the two void areas 12 simultaneously, reducing the possibility of bubbles or lack of glue and other situations between adjacent core boards 1.

[0041] Continuing to refer to Figures 3-5 , in the embodiment of the present application, exemplarily, in the plane where the filling area 121 is located, each filling piece 1211 is in a regular hexagon or rectangle shape, and the widths of the air guiding gaps 122 between adjacent filling pieces 1211 are kept consistent. Thus, when the molten prepreg 2 enters the air guiding gap 122, it can fill the air guiding gap 122 at the same time, reducing the possibility of forming bubbles when prepreg 2 enters the air guiding gap 122, and the molten prepreg 2 can also enter the air guiding area 123 and be filled in the air guiding area 123.

[0042] By adopting the above technical solution, when the molten prepreg 2 enters the air guiding gap 122 and the air guiding area 123, the air guiding gaps 122 with the same width can ensure that prepreg 2 fills the air guiding gap 122 and the air guiding area 123 at the same time, thereby reducing the possibility of forming bubbles when prepreg 2 enters the air guiding gap 122 or the air guiding area 123.

[0043] Referring to Figures 3-5, in an embodiment of the present application, exemplarily, one or more of a signal line 124, an independent hole 125, and a marking center point 126 may also be provided in the open area 12; it is easy to understand that on the core board 1, the signal line 124 located in the functional area 11 may sometimes be arranged in the open area 12; on the printed circuit board, an independent hole 125 that penetrates the thickness direction of the printed circuit board, that is, the first direction, is usually provided; and the marking center point 126 usually plays a positioning role on the core board 1; in the open area 12 of the same core board 1, there may be a signal line 124, an independent hole 125, and a marking center point 126, or the above structures may not be present.

[0044] When arranging the filling area 121 in the open area 12, the distances between the signal line 124 and the filling area 121, and between the independent hole 125 and the filling area 121 are both greater than 105 mil; and the distance between the marking center point 126 and the filling area 121 is greater than 3 mm, so as to reduce the certain influence of the filling area 121 on the normal use of the signal line 124, the independent hole 125, and the marking center point 126.

[0045] By adopting the above technical solution, when arranging the filling area 121 in the open area 12, the distance between the signal line 124 and the filling area 121 being greater than 105 mil can prevent the filling sheet 1211 from contacting the signal line 124, reducing the possibility of the signal line 124 short-circuiting and thus affecting the normal use of the signal line 124; currently, when processing the independent hole 125, usually the adjacent core boards 1 are first connected by a prepreg 2, and then the multi-layer core boards 1 are pressed together to fix the multi-layer core boards 1, and then the multi-layer core boards 1 are drilled to form the independent hole 125. And setting the distance between the independent hole 125 and the filling area 121 to be greater than 105 mil can ensure that when drilling the multi-layer core boards 1, the filling sheet 1211 near the independent hole 125 will not be driven to the adjacent core board 1, thus preventing the adjacent core board 1 from short-circuiting; as for setting the distance between the marking center point 126 and the filling area 121 to be greater than 3 mm, it can ensure that the marking center point 126 is not affected by the filling sheet 1211, thus ensuring the accuracy of the positioning of the marking center point 126.

[0046] The following describes the specific layout in the open area 12 of the core board 1 when the filling sheet 1211 is of different shapes. Continuing to refer to Figures 1-5, in the application embodiment, exemplarily, in the plane where the filling area 121 is located, a plurality of filling sheets 1211 are uniformly laid in the filling area 121, and each filling sheet 1211 is in a regular hexagon shape, that is, the filling area 121 as a whole is in a honeycomb shape, and the air guiding gap 122 is located between adjacent filling sheets 1211. As for the size of each filling sheet 1211, exemplarily, the side length of the filling sheet 1211 is greater than or equal to 1.2 mm and less than or equal to 1.8 mm; in the first direction, the thickness of the filling sheet 1211 is less than or equal to 2OZ; the width of the air guiding gap 122 is greater than or equal to 0.24 mm and less than or equal to 0.36 mm.

[0047] By adopting the above technical solution, when the thickness of the filling sheet 1211 is less than or equal to 2OZ and the width of the air guiding gap 122 is greater than or equal to 0.24 mm and less than or equal to 0.36 mm, when the semi-cured sheet 2 in a molten state enters the air guiding gap 122, it can not only contact with the substrate 13 with a sufficient area at the air guiding gap 122, but also ensure that the air guiding gap 122 is within a certain limit of size, thereby reducing the possibility of forming bubbles in the air guiding gap 122 and ensuring the stability of the fixation of the semi-cured sheet 2 to the adjacent core board 1.

[0048] And the multiple filling sheets 1211 can be installed on the substrate 13 of the core board 1 in various ways, so as to form the filling area 121 by using the multiple filling sheets 1211 and be able to form the air guiding gap 122 between adjacent filling sheets 1211. For example, copper sheets can be laid on the substrate 13 of the open area 12 of the core board 1, and then the copper sheets corresponding to the air guiding gap 122 are removed by etching solution, so as to expose the substrate 13 of the core board 1 to form the air guiding gap 122; or the air guiding gap 122 can be cut out on the copper sheet by using a cutting device.

[0049] It is easy to understand that when the partial copper sheets on the substrate 13 are removed by using the etching solution to form the functional area 11 and the open area 12 of the core board 1, the copper sheets in the open area 12 of the core board 1 can be directly processed, that is, the filling sheets 1211 in the filling area 121 are reserved, and the air guiding gap 122 is etched out by using the etching solution, so as to directly form the filling area 121 and a plurality of air guiding gaps 122 in the open area 12 of the core board 1, making the processing process of the core board 1 more convenient.

[0050] Refer to Figure 3, Exemplarily, in the plane where the filling area 121 is located, the filling sheet 1211 is a regular hexagon, and the side length of the filling sheet 1211 is set to 1.5 mm, and the width of the air guiding gap 122 is set to 0.3 mm; in the first direction, the thickness of the filling sheet 1211 is 2OZ, so that the shape of the filling sheet 1211 is more uniform. At the same time, when the filling sheet 1211 is a regular hexagon, the thickness of the filling sheet 1211 is set to 2OZ, and the thickness of the filling sheet 1211 will not affect the etching process or cutting process of the copper sheet, and thus the process of installing the filling sheet 1211 on the core board 1 substrate 13 can be made more convenient.

[0051] Referring to Figure 4 , in the embodiment of the present application, exemplarily, in the plane where the filling area 121 is located, a plurality of filling sheets 1211 are uniformly laid in the filling area 121, and each filling sheet 1211 is a rectangle, that is, the filling area 121 as a whole is in the shape of a city wall, and the length of each filling sheet 1211 is greater than or equal to 1.6 mm and less than or equal to 2.4 mm, and the width of each filling sheet 1211 is greater than or equal to 0.4 mm and less than or equal to 0.6 mm; the width of the air guiding gap 122 is greater than or equal to 0.4 mm and less than or equal to 0.6 mm.

[0052] By adopting the above technical solution, when the semi-cured sheet 2 in a molten state enters the air guiding gap 122, it can not only contact with the substrate 13 with a sufficient area at the air guiding gap 122, but also ensure that the air guiding gap 122 is within a certain limit of size, thereby reducing the possibility of forming bubbles in the air guiding gap 122 and ensuring the stability of the fixation of the semi-cured sheet 2 to the adjacent core board 1; and the filling sheet 1211 is set as a rectangle, making the method of fixing the filling sheet 1211 on the core board 1 substrate 13 simpler. For example, when forming the air guiding gap 122 by etching or cutting the copper sheet, the structure of the filling sheet 1211 set as a rectangle is simpler, so that the formation process of the filling area 121 and the air guiding gap 122 is more convenient.

[0053] Referring to Figure 4 and Figure 5 , in the embodiment of the present application, exemplarily, in the plane where the core board 1 is located, the core board 1 extends in the second direction. When using the semi-cured sheet 2 to connect adjacent core boards 1 and laminate multiple core boards 1, since it is necessary to heat-melt the semi-cured sheet 2 and fill the semi-cured sheet 2 in the air guiding gap 122, it is necessary to make the adjacent core boards 1 form relative sliding in the second direction, so that the semi-cured sheet 2 in a molten state can be fully filled in the air guiding gap 122, reducing the possibility of forming bubbles in the air guiding gap 122.

[0054] When the air guiding gap 122 extends along the second direction and the multi-layer core boards 1 are pressed together, the air guiding gap 122 communicates with the air guiding area 123. When the semi-cured sheet 2 in a molten state enters the air guiding area 123 through the air guiding gap 122, it may accumulate at the connection between the air guiding gap 122 and the air guiding area 123, so that the semi-cured sheet 2 cannot enter the air guiding area 123 and cannot contact the base material 13 at the air guiding area 123. Furthermore, the semi-cured sheet 2 cannot contact the base material 13 at the air guiding area 123, resulting in the formation of bubbles or lack of glue.

[0055] Continue to refer to Figure 4 and Figure 5 Therefore, in the embodiments of the present application, exemplarily, a preset angle is formed between the length direction of the filling sheet 1211 and the second direction, and the preset angle is greater than or equal to 60° and less than or equal to 80°; for example, the preset angle can be set to 70°. Or, the width direction of the filling sheet 1211 can also form a certain angle with the second direction. The embodiments of the present application do not further limit this, so that the extending direction of part of the air guiding gap 122 can form a certain angle with the second direction, reducing the possibility of the semi-cured sheet 2 accumulating at the connection between the air guiding gap 122 and the air guiding area 123.

[0056] By adopting the above technical solution, when the semi-cured sheet 2 is placed between adjacent core boards 1 and the multi-layer core boards 1 are pressed together, the adjacent core boards 1 slide relatively in the second direction, and the semi-cured sheet 2 in a molten state fills the air guiding gap 122, so that the semi-cured sheet 2 in a molten state is fully filled in the air guiding gap 122. When the semi-cured sheet 2 in a molten state enters the air guiding area 123 through the air guiding gap 122, it will not accumulate at the connection between the air guiding gap 122 and the air guiding area 123, reducing the possibility of forming bubbles or lack of glue.

[0057] It is worth mentioning that setting the filling sheet 1211 as a rectangle makes the method of fixing the filling sheet 1211 on the base material 13 of the core board 1 simpler. For example, when forming the air guiding gap 122 by etching or cutting a copper sheet, the structure of the filling sheet 1211 set as a rectangle is simpler. At this time, in the first direction, the thickness of the filling sheet 1211 can be greater than or equal to 2OZ, so that the selection range of the thickness of the copper sheet on the core board 1 is wider, and the application range of the filling sheet 1211 and the filling area 121 is also wider; exemplarily, the thickness of the filling sheet 1211 can be selected as 2.5OZ or 3OZ. The embodiments of the present application do not further limit this.

[0058] It is easy to understand that, in the embodiments of the present application, exemplarily, the filling sheet 1211 can also be selected in the shape of an equilateral triangle, etc., as long as the stability of the filling sheet 1211 laid on the base material 13 of the core board 1 can be ensured. The present application does not further limit this.

[0059] In summary, when manufacturing a printed circuit board, the core board 1 is first manufactured, and the specific process is as follows: Copper sheets are laid on the substrate 13, and then part of the copper sheets on the substrate 13 are removed using etching solution, so as to form the functional area 11 and the open area 12 of the core board 1; Then copper sheets are laid on the substrate 13 in the open area 12 of the core board 1, and then the copper sheets corresponding to the air guiding gaps 122 are removed through the etching solution, so that the substrate 13 of the core board 1 is exposed to form the air guiding gaps 122; Alternatively, a cutting device can be used to cut a plurality of air guiding gaps 122 in the copper sheets, so as to form the air guiding area 123, the filling area 121 and the air guiding gaps 122.

[0060] Subsequently, a plurality of core boards 1 are stacked, then the prepreg 2 is placed between two adjacent core boards 1, and then the prepreg 2 is heated so that the prepreg 2 is in a molten state. Then the multi-layer core boards 1 are pressed together, so that the molten prepreg 2 can fill the air guiding gaps 122, and the gas in the air guiding gaps 122 can be discharged through the air guiding gaps 122, thereby fixing the adjacent core boards 1, without directly filling in the relatively large open area 12, thus reducing the possibility of bubbles or lack of glue.

[0061] The embodiment of the present application also provides an electronic device, including the above-mentioned printed circuit board. By adopting the above technical solution, in the open area 12 of the core board 1 of the printed circuit board, the prepreg 2 is dispersedly filled in the air guiding gaps 122 between adjacent filling sheets 1211 and fixes the adjacent core boards 1, so that there is no need to directly fill in the open area 12, thus reducing the possibility of bubbles or lack of glue.

[0062] Those skilled in the art will readily think of other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include the common general knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and examples are only regarded as exemplary, and the true scope and spirit of the present application are pointed out by the following claims.

[0063] It should be understood that the present application is not limited to the precise structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A printed circuit board, characterized in that, It includes a plurality of core boards arranged at intervals in the first direction. A prepreg is provided between every two adjacent core boards. The prepreg is used to fix the two adjacent core boards. The prepreg can be heated to a molten state. When the plurality of core boards are pressed together, the adjacent core boards slide relative to each other in the second direction so that the molten prepreg fills the air guide gap. Among the plurality of core boards, at least one core board is provided with at least one open area. A filling area is provided in the open area. A plurality of filling sheets are provided in the filling area. An air guide gap is formed between adjacent filling sheets. The prepreg is at least partially arranged in the air guide gap. Taking the plane where the filling area is located as a cross-section, the cross-section of each filling sheet is a regular hexagon or a rectangle. The filling sheet is rectangular, and the length of the filling sheet is greater than or equal to 1.6 mm and less than or equal to 2.4 mm. The width of the filling sheet is greater than or equal to 0.4 mm and less than or equal to 0.6 mm. The width of the air guide gap is greater than or equal to 0.4 mm and less than or equal to 0.6 mm. Taking the plane where the filling area is located as a cross-section, all the air guide gaps are provided with the same width. The core board extends in the second direction. The length direction of the filling sheet forms a preset angle with the second direction. The preset angle is greater than or equal to 60° and less than or equal to 80°. The preset angle is used to reduce the aggregation of the molten prepreg at the connection of the air guide gap and the air guide area. The open area is further provided with an air guide area. The air guide area is arranged around the outside of the filling area. The air guide area is communicated with the air guide gap. The base material of the core board in the air guide area is exposed. The molten prepreg can enter and fill the air guide area. When the plurality of core boards are pressed together, the molten prepreg enters the air guide gap. The gas in the air guide gap is discharged to the air guide area through the air guide gap. The air guide gaps with the same width enable the prepreg to fill the air guide gap and the air guide area at the same time.

2. The printed circuit board according to claim 1, wherein The filling sheet is a regular hexagon, and the side length of the filling sheet is greater than or equal to 1.2 mm and less than or equal to 1.8 mm. In the first direction, the thickness of the filling sheet is less than or equal to 2OZ. The width of the air guide gap is greater than or equal to 0.24 mm and less than or equal to 0.36 mm.

3. The printed circuit board according to claim 1 or 2, characterized in that, One or more of signal lines, independent holes, and marking center points are provided in the open area. The distance between the signal line and the filling area, and the distance between the independent hole and the filling area are both greater than 105 mil. The distance between the marking center point and the filling area is greater than 3 mm.

4. The printed circuit board according to claim 1, wherein In the first direction, open areas are provided on both adjacent core boards, and the filling areas on the adjacent core boards are arranged oppositely.

5. An electronic device, characterized in that, It includes a printed circuit board according to any one of claims 1-4.

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