Shielding cover, circuit board assembly and electronic equipment

Abstract

The utility model discloses a shielding case, a circuit board assembly and electronic equipment, and belongs to the technical field of electronic equipment. The circuit board assembly comprises a circuit board, a shielding cover and a first component. The shielding case is mounted on the circuit board, and an accommodating cavity is formed between the shielding case and the circuit board; the first component is installed on the circuit board and located in the containing cavity. Wherein the shielding cover comprises a cover top part and an enclosure part, the enclosure part is arranged on the circumferential edge of the cover top part, a first through hole is formed in the cover top part, and the first through hole and the first component are oppositely arranged. According to the invention, the risk of tin connection of the welding spots between the first component and the circuit board can be reduced or avoided.

Description

Technical Field

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

[0002] Underfill may be applied between the device components (such as device chips) and the device circuit board within the shielding device cover of an electronic device's printed circuit board assembly (PCBA). During PCB assembly rework, when the device components within the cover need to be repaired, the cover must be heated to remove it from the device circuit board. During the heating process, solder bridging may occur between the solder balls at the solder joints between the device components and the device circuit board. Utility Model Content

[0003] The present application provides a shielding cover, a circuit board assembly, and an electronic device to solve the technical problem of bridging that is prone to occur in related technologies.

[0004] The technical solution is as follows:

[0005] According to a first aspect of the present application, a circuit board assembly is provided, comprising: a circuit board, a shielding cover, and a first component; the shielding cover is mounted on the circuit board, and a receiving cavity is formed between the shielding cover and the circuit board; the first component is mounted on the circuit board, and the first component is located in the receiving cavity; wherein the shielding cover comprises a cover top and a blocking portion, the blocking portion is arranged at the circumferential edge of the cover top, a first through hole is arranged on the cover top, and the first through hole is arranged opposite to the first component.

[0006] By adopting the above technical solution, a first through hole is provided at the top of the top of the cover, so that a thermally conductive material can be conveniently added between the shielding cover and the first component. In this way, when the shielding cover is removed by heating the shielding cover, the heat of the first component inside the shielding cover can be transferred to the shielding cover through the thermally conductive material, so as to reduce or avoid the risk of bridging the solder joints between the first component and the circuit board.

[0007] In some implementations, the orthographic projection of the first through hole in the set plane is located in the middle of the orthographic projection of the first component in the set plane, and the set plane is perpendicular to the thickness direction of the circuit board.

[0008] By adopting the above technical solution, when the orthographic projection of the first through hole is located in the middle of the orthographic projection of the first component, when the thermal conductive material is added through the first through hole, the thermal conductive material can be spread from the middle of the surface of the first component to the surrounding areas, which is conducive to achieving uniform spreading of the thermal conductive material on the surface of the first component, thereby maximizing the contact area between the thermal conductive material and the first component, which is beneficial to the heat transfer of the first component and reduces or avoids the risk of damage to the first component during the heating process.

[0009] In some implementations, an observation hole is further provided on the top of the cover, and the observation hole corresponds to the edge of the first component.

[0010] By adopting the above technical solution, when the thermal conductive material flows from the middle of the surface of the first component to the surrounding areas, it is possible to observe whether the thermal conductive material has flowed to the edge of the surface of the first component by observing the through hole. This can reduce the possibility of the thermal conductive material overflowing from the surface of the first component onto the circuit board. This design can reduce the risk of the thermal conductive material contacting sensitive areas on the circuit board, such as electrical connection points or pads, thereby reducing electrical problems or mechanical interference caused by the thermal conductive material.

[0011] In some implementations, the top of the cover has an outer surface, and a hole masking tape is provided on the outer surface of the top of the cover, and the hole masking tape covers the first through hole.

[0012] By adopting the above technical solution, the hole masking tape can maintain the integrity of the outer surface of the top of the cover; the hole masking tape can also prevent solder, chemicals or other pollutants from entering the interior of the shielding cover through the first through hole.

[0013] In some implementations, the hole mask is provided with slits.

[0014] By adopting the above technical solution, the cut provides a natural tear line, making it easier to remove the perforated sticker and reducing damage caused by improper handling. This design helps to improve production efficiency and product consistency.

[0015] In some implementations, the slit includes multiple sub-slits, and one end of the length direction of the multiple sub-slits intersects.

[0016] By adopting the above technical solution, the hole masking sticker is designed with multiple sub-slits and one end of them intersecting, so that the hole masking sticker can overlap with the hole center of the first through hole as much as possible, which facilitates positioning and improves the overall aesthetics.

[0017] In some implementations, an underfill is provided between the first component and the circuit board.

[0018] By adopting the above technical solution, the underfill can improve the reliability of the solder joint between the first component and the circuit board. When the shielding cover needs to be removed for maintenance, the first through hole can be used to add thermal conductive material into the shielding cover to reduce the possibility of solder joints in the underfill becoming brittle.

[0019] In some implementations, the first component is a chip.

[0020] By adopting the above technical solution, when the first component is a chip, a thermal conductive material can be added by opening a first through hole on the top of the cover, which is beneficial to protecting the chip and reducing the possibility of damage to the chip.

[0021] In some implementations, a second through hole is further provided on the top of the cover, and the second through hole corresponds to an edge of the first component.

[0022] By adopting the above technical solution, the second through hole is used to facilitate adding bottom filling glue to the solder joint part between the first component and the circuit board.

[0023] In some implementations, the orthographic projection of the second through hole in the set plane partially overlaps or is separated from the orthographic projection of the first component in the set plane, and the set plane is perpendicular to the thickness direction of the circuit board.

[0024] By adopting the above technical solution, it is relatively easy to achieve that the bottom filling glue flows from the edge of the first component into between the first component and the circuit board. In addition, the second through hole can also be used as an observation through hole to observe whether the thermal conductive material has flowed into place.

[0025] In some implementations, the circuit board assembly further includes a heat-conducting structure disposed between the top of the cover and the first component.

[0026] By adopting the above technical solution, the heat-conducting structure is formed of a heat-conducting material, which can also be added through the first through hole when the circuit board assembly is assembled and shipped out of the factory. In this way, it can be added in advance to facilitate subsequent maintenance; it is also beneficial to the heat dissipation of the first component.

[0027] In some implementations, the cover top has an inner surface, the first component has a first surface, the inner surface of the cover top and the first surface are arranged opposite to each other, and the heat conductive structure contacts the inner surface and the first surface of the cover top respectively.

[0028] By adopting the above technical solution, it is easy to achieve that the heat of the first component can be transferred to the outside through the heat-conducting structure, thereby reducing the possibility of bridging of the solder joints between the first component and the circuit board.

[0029] In some implementations, the thermally conductive structure is a thermally conductive gel.

[0030] By adopting the above technical solution, thermally conductive gel is a material used for heat dissipation management in electronic devices, suitable for applications requiring efficient heat conduction and flexible adhesion. Its thermal conductivity is generally higher than that of air, effectively transferring heat from a high-temperature source (such as the primary component) to a heat sink or other thermal management system. Thermally conductive gel includes a thermally conductive filler (such as boron nitride, aluminum oxide, silicon nitride), a base material (such as silicone, polyurethane, acrylic), a thickener, and a curing agent.

[0031] In some implementations, the cover top has an inner surface, the first component has a first surface, and a distance between the first surface and the inner surface of the cover top in a thickness direction of the circuit board is 0.1 mm to 3 mm.

[0032] By adopting the above technical solution, it is easy to fill and spread the thermal conductive material onto the surface of the first component.

[0033] In some implementations, a distance between the first surface and the inner surface of the cover top in a thickness direction of the circuit board is 0.1 mm, 0.5 mm, 1 mm, 2 mm, or 3 mm.

[0034] By adopting the above technical solution, it is easy to fill and spread the thermal conductive material onto the surface of the first component.

[0035] In some implementations, the diameter of the first through hole is 0.3 mm to 3 mm.

[0036] By adopting the above technical solution, by limiting the aperture of the first through hole, it is convenient to add the heat-conducting material on the one hand, and on the other hand, it can also reduce the impact of the aperture being too large on the shielding performance of the shielding cover.

[0037] In some implementations, the first through hole has a diameter of 0.3 mm, 0.5 mm, 1 mm, 1.5 mm, or 3 mm.

[0038] By adopting the above technical solution, by limiting the aperture of the first through hole, it is convenient to add the heat-conducting material on the one hand, and on the other hand, it can also reduce the impact of the aperture being too large on the shielding performance of the shielding cover.

[0039] A second aspect of the present application provides a circuit board assembly, comprising: a circuit board, a shielding cover and a first component; the shielding cover is installed on the circuit board, and a accommodating cavity is formed between the shielding cover and the circuit board; the first component is installed on the circuit board, and the first component is located in the accommodating cavity; wherein, the shielding cover includes a cover top and a blocking portion, the blocking portion is arranged at the circumferential edge of the cover top, and a heat-conducting structure is arranged between the cover top and the first component.

[0040] By adopting the above technical solution, a heat-conducting structure is set between the shielding cover and the first component. In this way, when the shielding cover is removed by heating the shielding cover, the heat of the first component inside the shielding cover can be transferred to the shielding cover through the heat-conducting structure, so as to reduce the possibility of bridging the solder joints between the first component and the circuit board, thereby facilitating the normal function of the first component.

[0041] In some implementations, an underfill is provided between the first component and the circuit board.

[0042] By adopting the above technical solution, the bottom filler can improve the reliability of the solder joint between the first component and the circuit board. When the shielding cover needs to be removed for maintenance, the thermal conductive structure can reduce the possibility of solder joints in the bottom filler being tinned.

[0043] A third aspect of the present application provides a shielding cover for covering a first component of an electronic device. The shielding cover includes a cover top and a surrounding portion. The surrounding portion is arranged at the circumferential edge of the cover top. A first through hole is provided on the cover top. The first through hole is arranged opposite to the first component. The first through hole is used for allowing a heat-conducting structure to pass through so that the heat-conducting structure can be filled into the interior of the shielding cover.

[0044] By adopting the above technical solution, when the shielding cover is applied to an electronic device, a first through hole is provided at the top of the cover, so that a thermal conductive material can be conveniently added between the shielding cover and the first component. In this way, when the shielding cover is removed by heating the shielding cover, the heat of the first component inside the shielding cover can be transferred to the shielding cover through the thermal conductive material, thereby reducing the possibility of bridging of the solder joints between the first component and the circuit board.

[0045] In some implementations, an observation through hole is further provided on the top of the cover, and the observation through hole is used to correspond to the edge of the first component.

[0046] By adopting the above technical solution, when the thermal conductive material flows from the middle of the surface of the first component to the surrounding areas, it is possible to observe whether the thermal conductive material has flowed to the edge of the surface of the first component by observing the through hole. This can reduce the possibility of the thermal conductive material overflowing from the surface of the first component onto the circuit board. This design can reduce the risk of the thermal conductive material contacting sensitive areas on the circuit board, such as electrical connection points or pads, thereby reducing electrical problems or mechanical interference caused by the thermal conductive material.

[0047] In some implementations, the diameter of the first through hole is 0.3 mm to 3 mm.

[0048] By adopting the above technical solution, by limiting the aperture of the first through hole, it is convenient to add the heat-conducting material on the one hand, and on the other hand, it can also reduce the impact of the aperture being too large on the shielding performance of the shielding cover.

[0049] A fourth aspect of the present application provides an electronic device, which includes the circuit board assembly in any of the above implementations, or the shielding cover in any of the above implementations.

[0050] By adopting the above technical solution, when the shielding cover is removed by heating the shielding cover, the risk of bridging the solder joints between the first component and the circuit board can be reduced or avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 is a structural diagram of an electronic device provided in an embodiment of the present application;

[0052] Figure 2 is a structural schematic diagram of an electronic device provided by an embodiment of the present application from another perspective;

[0053] Figure 3 It is a schematic diagram of a partial structure of a circuit board assembly in the related art;

[0054] Figure 4 It is another partial structural diagram of a circuit board assembly in the related art;

[0055] Figure 5 is a cross-sectional view of a partial structure of a circuit board assembly provided in an embodiment of the present application;

[0056] Figure 6 is a top view of a partial structure of a circuit board assembly provided in an embodiment of the present application;

[0057] Figure 7 is another top view of a partial structure of a circuit board assembly provided in an embodiment of the present application;

[0058] Figure 8 is another cross-sectional view of a partial structure of a circuit board assembly provided in an embodiment of the present application;

[0059] Figure 9 This is a schematic diagram of the process from adding thermal conductive material to repairing a circuit board assembly provided by an embodiment of the present application;

[0060] Figure 10 This is a structural diagram of another circuit board assembly provided in an embodiment of the present application;

[0061] Figure 11 It is a temperature curve diagram of the device cover and the device chip in the related art;

[0062] Figure 12 This is a temperature curve diagram of the shielding cover and the first component in the embodiment of the present application.

[0063] The meanings of the figures are as follows:

[0064] 101. Device circuit board; 103. Device cover; 104. Device chip; 106. Bottom filler; 107. Board-to-board connector; 108. Corner structure;

[0065] 201, display screen; 202, housing; 203, circuit board assembly; 204, device frame; 205, back cover;

[0066] 301. Circuit board; 302. Shielding cover; 303. First component; 304. Accommodating cavity; 305. Top of the cover; 306. Enclosing portion; 307. First through hole; 308. First side; 309. Second side; 310. Second component; 311. Electronic component; 312. Outer surface; 313. Inner surface; 314. First surface; 315. Observation through hole; 316. Second through hole; 317. Hole-masking sticker; 318. Cutting seam; 319. Sub-slit; 320. Thermal conductive structure; 321. Solder ball.

[0067] 401. Feeding tool; 402. Heat sink. DETAILED DESCRIPTION

[0068] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0069] It should be understood that the “multiple” mentioned in this application refers to two or more. In the description of this application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; “and / or” in this article is merely a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in order to facilitate the clear description of the technical solution of this application, words such as “first” and “second” are used to distinguish between identical or similar items with basically the same functions and effects. Those skilled in the art can understand that words such as “first” and “second” do not limit the quantity and execution order, and words such as “first” and “second” do not necessarily limit them to be different.

[0070] Figure 1 is a structural diagram of an electronic device provided in an embodiment of the present application, Figure 2 This is a structural diagram of an electronic device provided by an embodiment of the present application from another perspective, combined with Figure 1 and Figure 2As shown, in one or more embodiments, the electronic device includes a display screen 201, a housing 202 and a printed circuit board assembly 203 (PCBA); the housing 202 includes a device frame 204 and a back cover 205, the display screen 201 and the back cover 205 are respectively located on opposite sides of the device frame 204 in the thickness direction, and form a device cavity, and the circuit board assembly 203 is installed in the device cavity.

[0071] For example, the electronic device may be a mobile phone, tablet computer, notebook, smart watch, or e-reader. The mobile phone may be a foldable phone or a bar phone. The electronic device may also be referred to as a terminal device.

[0072] Figure 3 This is a partial structural diagram of the circuit board assembly 203 in the related art, see Figure 3 As shown, in the related art, the circuit board assembly 203 includes a device circuit board 101, device components and a device cover 103; Figure 4 This is another partial structural diagram of the circuit board assembly 203 in the related art. Figure 4 The device circuit board 101 is Figure 3 On the other side of the device circuit board 101, Figure 4 FIG shows a device cover 103 on the other side of the device circuit board 101, and a corner structure 108 of the device cover 103 on this side corresponds to the position of the device chip 104 on the other side. Figure 3 and Figure 4 As shown, when device components, such as device chip 104, are located in an integrated device cover 103 for shielding, and when a stress source exists on the other side of the device circuit board 101 (the stress source may be a board-to-board connector for connecting to a camera on the other side of the device circuit board 101 or a corner structure 108 of another device cover 103 on the other side of the device circuit board 101), in order to improve the reliability of the solder joints of the device chip 104, underfill glue, i.e., bottom filling glue, is applied to the bottom of the device chip 104. During the repair process of the circuit board assembly 203, when it is necessary to repair the device components in the device cover 103 (the device components may be the device chip 104 or other components), the device cover 103 needs to be removed from the device circuit board 101 by heating. During the heating process of the device cover 103, the heat dissipation metal block or heat dissipation pad cannot directly act on the chip, and tin bridging may occur between the solder balls at the solder joint positions between the device components in the bottom filling glue and the device circuit board 101, thereby causing the device components to be scrapped or the number of times the device circuit board 101 components are returned for repair exceeds the standard, which may lead to the scrapping of the circuit board assembly 203.

[0073] To this end, the embodiment of the present application provides a shielding cover 302 and a circuit board assembly 203 to solve the problems in the related art. The shielding cover 302 and the circuit board assembly 203 provided in the embodiment of the present application are described in detail below.

[0074] Figure 5 This is a cross-sectional view of a partial structure of the circuit board assembly 203 provided in an embodiment of the present application, see Figure 5 As shown, in one or more embodiments, the circuit board assembly 203 provided in the present application includes: a circuit board 301, a shielding cover 302 and a first component 303; the shielding cover 302 is installed on the circuit board 301, and an accommodating cavity 304 is formed between the shielding cover 302 and the circuit board 301; the first component 303 is installed on the circuit board 301, and the first component 303 is located in the accommodating cavity 304; wherein, the shielding cover 302 includes a cover top 305 and a blocking portion 306, the blocking portion 306 is arranged at the circumferential edge of the cover top 305, and a first through hole 307 is provided on the cover top 305, and the first through hole 307 is arranged opposite to the first component 303. In this way, the circuit board assembly 203 provided in at least one embodiment is provided with a first through hole 307 at the top of the cover top 305, so that thermal conductive material can be easily added between the shielding cover 302 and the first component 303. In this way, when the shielding cover 302 is removed by heating the shielding cover 302, the heat of the first component 303 inside the shielding cover 302 can be transferred to the shielding cover 302 through the thermal conductive material, so as to reduce or avoid the risk of bridging of the solder joints between the first component 303 and the circuit board 301.

[0075] See also Figure 5As shown, in some embodiments, the circuit board 301 has a first side surface 308 and a second side surface 309 relative to each other, and at least one of the first side surface 308 and the second side surface 309 is provided with a shielding cover 302. A first component 303 can be provided in the shielding cover 302 in at least one side surface. The number of first components 303 located in the shielding cover 302 can be one or more. When the number of first components 303 in the shielding cover 302 is multiple, the number can be 2 or 3. The specific number can also be determined according to actual needs, and this application does not make specific limitations. Illustratively, a shielding cover 302 is provided on the first side 308, and a shielding cover 302 is provided on the second side 309. A first component 303 is provided in at least one shielding cover 302 located on the first side 308. The circuit board assembly 203 further includes a second component 310. The second component 310 is provided in the shielding cover 302 located on the second side 309. No underfill 106 is provided between the second component 310 and the circuit board 301. The second side 309 may also be provided with a board-to-board connector 107, which is located outside the shielding cover 302. The number of shielding covers 302 on each of the first side 308 and the second side 309 can be one or more. When the number is multiple, the number of shielding covers 302 on each side can be two, three, or four, etc., which is not specifically limited in this application. Other types of electronic components 311 besides the first component 303 may be installed in the shielding cover 302 located on the first side 308 ; similarly, other types of electronic components 311 besides the second component 310 may be installed in the shielding cover 302 located on the second side 309 .

[0076] See also Figure 5 As shown, in some embodiments, the cover top 305 and the enclosure 306 are an integral structure, for example, they can be made using an integral molding process, such as stamping or die-casting. It is understood that other integral molding processes can also be used. The shielding cover 302 can be made of metal, such as copper, aluminum alloy, or stainless steel.

[0077] In some embodiments, the first component 303 is a chip. When the first component 303 is a chip, a first through hole 307 can be provided in the cover top 305 to allow for thermal conductivity to be added. This helps protect the chip and reduces or prevents the risk of damage. Exemplarily, the chip is a baseband chip or a radio frequency chip; Exemplarily, the chip can be an RFIC chip, i.e., a radio frequency integrated circuit chip; or, the chip can be a WIFI chip, i.e., a wireless local area network chip.

[0078] See also Figure 5As shown, in some embodiments, an underfill 106 is provided between the first component 303 and the circuit board 301. The underfill 106 can improve the reliability of the solder joints between the first component 303 and the circuit board 301. Since the underfill 106 is filled between the first component 303 and the circuit board 301, when the shielding cover 302 needs to be removed by heating, the solder balls 321 in the underfill 106 are prone to bridging. After a first through hole 307 is provided on the top of the shielding cover 302 opposite to the first component 303, when the shielding cover 302 is removed for repair, a thermal conductive material is added between the shielding cover 302 and the first component 303 before heating. In this way, the heat of the first component 303 inside the shielding cover 302 can be transferred to the shielding cover 302 through the thermal conductive material. This is to reduce the possibility of bridging of the solder balls 321 at the solder joints between the first component 303 and the circuit board 301; and when the first component 303 in the shielding cover 302 is not damaged before heating, since the possibility of bridging of the solder joints between the first component 303 and the circuit board 301 can be reduced or avoided during the removal of the shielding cover 302, the normal use of the function of the first component 303 can still be guaranteed, and the risk of exceeding the number of times the equipment circuit board 101 assembly is returned for repair can be reduced or avoided, thereby reducing the risk of scrapping the circuit board assembly 203 and reducing maintenance costs.

[0079] It should be noted that, in the embodiment of the present application, a first through hole 307 is provided on the shielding cover 302 to allow heat conduction by adding a thermally conductive material. This can be applied to a situation where an underfill 106 is provided between the electronic component 311 in the shielding cover 302 and the circuit board 301, so as to reduce or avoid the occurrence of bridging of solder joints between the electronic component 311 and the circuit board 301. However, it is understandable that the technical solution of providing a first through hole 307 on the shielding cover 302 to allow heat conduction by adding a thermally conductive material can still be applied to a situation where there is no underfill 106. In addition, in some other possible situations, when the underfill 106 is also filled between the second component 310 in the shielding cover 302 located on the second side 309 and the circuit board 301, a first through hole 307 also needs to be provided on the shielding cover 302 located on the second side 309.

[0080] See also Figure 5As shown, in some embodiments, the cover top 305 has an outer surface 312 and an inner surface 313 that are opposite to each other, and the first component 303 has a first surface 314. The inner surface 313 and the first surface 314 of the cover top 305 are arranged opposite each other, and there is a distance between the inner surface 313 and the first surface 314 of the cover top 305 in the thickness direction of the circuit board 301. The distance between the first surface 314 and the inner surface 313 of the cover top 305 in the thickness direction of the circuit board 301 is 0.1 mm to 3 mm. This facilitates the filling and spreading of the thermal conductive material onto the surface of the first component 303.

[0081] In some embodiments, the distance between the first surface 314 and the inner surface 313 of the cover top 305 in the thickness direction of the circuit board 301 is: 0.1mm, 0.5mm, 1mm, 2mm or 3mm; this makes it easier to fill and spread the thermal conductive material to the surface of the first component 303; and when the distance is less than 0.1mm, the thermal conductive material may not be able to effectively spread and fill the surface of the first component 303; of course, in some other possible cases, when other methods are used that do not add thermal conductive material from the first through hole 307 or the thermal conductive material has better fluidity, the distance can be less than 0.1mm.

[0082] Figure 6 This is a top view of the partial structure of the circuit board assembly 203 provided in the embodiment of the present application, see Figure 6 As shown, in some embodiments, the first through hole 307 is a circular hole, which is convenient for matching with the nozzle of the feeding tool 401 for adding thermal conductive material. It should be noted that in some other possible implementations, the shape of the first through hole 307 can also be elliptical or polygonal; the polygon can be a quadrilateral or a hexagon.

[0083] See also Figure 6 As shown, in some embodiments, the orthographic projection of the first through-hole 307 within a set plane is located in the middle of the orthographic projection of the first component 303 within the set plane, and the set plane is perpendicular to the thickness direction of the circuit board 301. When the orthographic projection of the first through-hole 307 is located in the middle of the orthographic projection of the first component 303, when the thermal conductive material is added through the first through-hole 307, the thermal conductive material can be dispersed from the middle of the surface of the first component 303 to the surrounding area, which facilitates the uniform dispersion of the thermal conductive material on the surface of the first component 303, thereby maximizing the contact surface between the thermal conductive material and the first component 303, facilitating heat transfer from the first component 303, and reducing the possibility of damage to the first component 303 during heating.

[0084] It should be noted that the set plane can be any plane perpendicular to the thickness direction of the circuit board 301; the thickness direction of the circuit board 301 is parallel to the thickness direction of the electronic device, where the thickness direction of the circuit board 301 is the CC direction. In addition, the orthographic projection of the first through hole 307 within the set plane is located in the middle of the orthographic projection of the first component 303 within the set plane, which can mean that the center of the orthographic projection of the first through hole 307 within the set plane coincides with, or approximately coincides with, the center of the orthographic projection of the first component 303 within the set plane.

[0085] In some embodiments, the aperture of the first through hole 307 is 0.3 mm to 3 mm. Limiting the aperture of the first through hole 307 facilitates the addition of thermally conductive material while also minimizing the impact of an excessively large aperture on the shielding performance of the shielding cover 302. For example, the aperture is the diameter, and the aperture of the first through hole 307 is 0.3 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm, or 3 mm. Of course, the aperture of the first through hole 307 can be further specifically configured as needed.

[0086] See also Figure 6 As shown, in some embodiments, an observation hole 315 is further provided on the top 305 of the cover, and the observation hole 315 corresponds to the edge of the first component 303. When the thermal conductive material flows from the middle of the surface of the first component 303 to the surrounding areas, with the observation hole 315, it can be convenient to observe whether the thermal conductive material flows to the edge of the surface of the first component 303, thereby reducing the possibility of the thermal conductive material overflowing from the surface of the first component 303 to the circuit board 301. This design can reduce the contact of the thermal conductive material with sensitive areas on the circuit board 301, such as electrical connection points or pads, thereby reducing electrical problems or mechanical interference caused by the thermal conductive material. Exemplarily, the orthographic projection of the observation hole 315 in the set plane is separated from or partially overlapped with the orthographic projection of the first component 303 in the set plane, thereby making it convenient to observe whether the thermal conductive material flows to the edge of the surface of the first component 303. The shape of the observation hole 315 can be circular, elliptical or polygonal, such as Figure 5 As shown, the observation hole 315 is circular. The diameter of the observation hole 315 can be equal to or smaller than the diameter of the first through hole 307. For example, the diameter of the observation hole 315 can be 2 / 3 of the diameter of the first through hole 307, as long as the thermal conductive material can be easily observed through the observation hole 315. When the first component 303 is a quadrilateral, one or more observation holes 315 can be provided on each of the four sides of the first component 303. For example, each side can have one, two, or three observation holes 315.

[0087] See also Figure 6As shown, in some embodiments, the cover top 305 is further provided with a second through hole 316, which corresponds to the edge of the first component 303. The second through hole 316 is used to facilitate the addition of the underfill 106 to the solder joint between the first component 303 and the circuit board 301.

[0088] See also Figure 6 As shown, in some embodiments, the orthographic projection of the second through hole 316 within a set plane partially overlaps or separates from the orthographic projection of the first component 303 within the set plane, and the set plane is perpendicular to the thickness direction of the circuit board 301. This makes it easier to achieve the flow of underfill 106 from the edge of the first component 303 into the space between the first component 303 and the circuit board 301. In addition, the second through hole 316 can also be used to observe whether the thermal conductive material has flowed into place, just like the observation through hole 315.

[0089] Figure 7 This is another top view of the partial structure of the circuit board assembly 203 provided in the embodiment of the present application, see Figure 7 As shown, in some embodiments, a masking tape 317 is provided on the outer surface 312 of the cover top 305, and the masking tape 317 covers the first through hole 307. The masking tape 317 maintains the integrity of the outer surface 312 of the cover top 305 and prevents solder, chemicals, or other contaminants from entering the interior of the shielding cover 302 through the first through hole 307. The masking tape 317 can be rectangular or circular, or any other shape as long as it covers the first through hole 307. For example, the masking tape 317 can be made of paper or polyethylene terephthalate (PET) film. The hole masking sticker 317 may have been affixed when the circuit board assembly 203 is assembled and shipped out of the factory; or the hole masking sticker 317 may be affixed to the top 305 of the cover after the electronic components 311 in the shielding cover 302 are repaired and the shielding cover 302 is reinstalled on the circuit board 301.

[0090] In some embodiments, the hole masking tape 317 can also be used to cover the observation hole 315, thereby preventing solder, chemicals, or other contaminants from entering the interior of the shielding cover 302 through the observation hole 315. It is understood that the hole masking tape 317 can also be used to cover the second through hole 316, thereby preventing solder, chemicals, or other contaminants from entering the interior of the shielding cover 302 through the second through hole 316.

[0091] See also Figure 7As shown, in some embodiments, the hole masking tape 317 is provided with a slit 318, which can provide a natural tear line, making it more convenient to remove the hole masking tape 317 and reducing damage caused by improper handling. This design helps to improve production efficiency and product consistency.

[0092] See also Figure 7 As shown, in some embodiments, the slit 318 includes multiple sub-slits 319, and one end of the length direction of the multiple sub-slits 319 intersects. The design of the hole mask 317 using multiple sub-slits 319 and intersecting their ends facilitates the hole mask 317 to coincide with the hole center of the first through hole 307 as much as possible, facilitates positioning, and improves the overall aesthetics. For example, the number of sub-slits 319 can be 3, 4, 5 or 6, as shown in FIG. Figure 7 FIG. 3 shows that the number of sub-slits 319 is 4. FIG.

[0093] Figure 8 This is another cross-sectional view of the partial structure of the circuit board assembly 203 provided in the embodiment of the present application, see Figure 8 As shown, in some embodiments, the circuit board assembly 203 further includes a heat-conducting structure 320, which is disposed between the cover top 305 and the first component 303. The heat-conducting structure 320 is formed of a thermally conductive material and can also be added through the first through-hole 307 when the circuit board assembly 203 is assembled and shipped. This allows for early addition to facilitate subsequent maintenance and also facilitates heat dissipation from the first component 303.

[0094] See also Figure 8 As shown, in some embodiments, the thermally conductive structure 320 is in contact with the inner surface 313 and the first surface 314 of the cover top 305, respectively. This facilitates heat transfer from the first component 303 to the outside via the thermally conductive structure 320, reducing the possibility of solder joints between the first component 303 and the circuit board 301. Exemplarily, the inner surface 313 and the first surface 314 of the cover top 305 are spaced appropriately apart in the thickness direction of the circuit board 301, thereby facilitating the flow of thermally conductive material between the inner surface 313 and the first surface 314 of the cover top 305, thereby forming the thermally conductive structure 320.

[0095] In some embodiments, the thermally conductive structure 320 is a thermally conductive gel. Thermally conductive gel is a material used for heat dissipation management in electronic devices, suitable for applications requiring efficient heat conduction and flexible fit. Its thermal conductivity is typically higher than that of air, effectively transferring heat from a high-temperature source (such as the first component 303) to a heat sink or other thermal management system. Thermally conductive gel includes a thermally conductive filler (such as boron nitride, aluminum oxide, or silicon nitride), a base material (such as silicone, polyurethane, or acrylic), a thickener, and a curing agent.

[0096] Figure 9 This is a flow chart of the circuit board assembly 203 provided in the embodiment of the present application from adding thermal conductive material to the maintenance process; see Figure 9 As shown, Figure 9 FIG. 1( a ) shows a state diagram of adding heat-conducting material between the cover top 305 and the first component 303 using a feeding tool 401 and forming a heat-conducting structure 320 when the cover top 305 of the shielding cover 302 has a first through hole 307 . Figure 9 Figure (b) shows that a heat sink 402 is placed on the top 305 of the shielding cover 302. During the heating process of the shielding cover 302, the heat sink 402 can transfer the heat received by the chip to the outside, which can protect the chip and also facilitate the removal of the shielding cover 302. For example, the heat sink 402 can be made of copper or stainless steel.

[0097] It should be noted that, during the maintenance process, what can be removed is the shielding cover 302 located on the first side 308 and installed on the first component 303, so that the first component 303 and other types of electronic components 311 in the shielding cover 302 can be repaired or inspected; in addition, when the shielding cover 302 located on the second side 309 is heated and removed, the heat will be transferred to the first component 303 in the shielding cover 302 located on the first side 308, and it is also necessary to place a heat sink 402 on the shielding cover 302 located on the first side 308, so as to facilitate the heat dissipation of the first component 303 to protect the first component 303.

[0098] Figure 10 This is a structural diagram of another circuit board assembly 203 provided in an embodiment of the present application, see Figure 10 As shown, the circuit board assembly 203 includes: a circuit board 301, a shielding cover 302, and a first component 303. The shielding cover 302 is mounted on the circuit board 301, and a receiving cavity 304 is formed between the shielding cover 302 and the circuit board 301. The first component 303 is mounted on the circuit board 301 and is located in the receiving cavity 304. The shielding cover 302 includes a cover top 305 and a surrounding portion 306. The surrounding portion 306 is disposed at the circumferential edge of the cover top 305. A heat-conducting structure 320 is disposed between the cover top 305 and the first component 303. The heat-conducting structure 320 is disposed between the shielding cover 302 and the first component 303. When the shielding cover 302 is removed by heating the shielding cover 302, the heat of the first component 303 inside the shielding cover 302 can be transferred to the shielding cover 302 through the heat-conducting structure 320, thereby reducing the possibility of bridging of the solder joints between the first component 303 and the circuit board 301. It should be noted that Figure 10The top 305 of the shielding cover 302 may not be provided with the first through hole 307, and a heat conducting structure 320 may be provided directly between the top 305 and the first component 303. For example, the heat conducting structure 320 may be a heat conducting gel, which is the same as described above and will not be repeated here.

[0099] It is understandable that for Figure 10 The circuit board assembly 203 and Figure 5 The main difference between the circuit board assembly 203 is that Figure 10 The top 305 of the cover may not have the first through hole 307 and the observation through hole 315, so for Figure 10 For other structures of the circuit board assembly 203 shown in FIG, see Figure 5 The description of the related drawings will not be repeated here.

[0100] Figure 11 This is a temperature curve diagram of the device cover 103 and the device chip 104 in the related art, see Figure 11 As shown, curve L1 shows the temperature of device cover 103 changing over time; curve L2 shows the temperature of device chip 104 changing over time. The time it takes for device cover 103 to reach the set temperature is T1, and the time it takes for device chip 104 to reach the set temperature is T2. The difference between T2 and T1 is no less than 15 seconds. The set temperature can be 217 degrees Celsius. When this temperature is reached, device cover 103 can be easily removed. However, this temperature may cause solder joints at the chip's solder joints. Since the difference between T2 and T1 is no less than 15 seconds, there is no less than 15 seconds to remove device cover 103 before the chip reaches the set temperature.

[0101] Figure 12 3 is a temperature curve diagram of the shielding cover 302 and the first component 303 in the embodiment of the present application. The first component 303 is a chip. Figure 12 As shown, curve L3 is a curve showing the temperature of the shielding cover 302 changing with time; curve L4 is a curve showing the temperature of the first component 303 changing with time; the time when the temperature of the shielding cover 302 reaches the set temperature (such as 217 degrees Celsius) is T3, and the time when the first component 303 reaches the set temperature is T4, and the difference between T4 and T3 is not less than 30 seconds. Figure 12 and Figure 11 It can be seen that the difference between T4 and T3 is about twice the difference between T2 and T1, that is, the present application has at least 30 seconds to remove the shielding cover 302 before the first component 303 reaches the set temperature, which greatly reduces or avoids the risk of solder joints in the first component 303. Figure 11 The device cover 103 and Figure 12 The shielding cover 302 in the same material and shape is different from Figure 11 The device cover 103 in the embodiment does not have the first through hole 307 and the observation through hole 315; Figure 11 Device chip 104 and Figure 12 The first component 303 in the embodiment uses the same chip, which makes comparison easier.

[0102] In the description of the specification of this application, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A circuit board assembly, characterized in that: include: circuit boards; A shielding cover is mounted on the circuit board, with an accommodating cavity formed between the shielding cover and the circuit board; a first component, the first component being mounted on the circuit board and located in the accommodating cavity; The shielding cover includes a cover top and a blocking portion, the blocking portion is arranged at the circumferential edge of the cover top, and a first through hole is provided on the cover top, and the first through hole is arranged opposite to the first component.

2. The circuit board assembly according to claim 1, wherein: The orthographic projection of the first through hole in a set plane is located in the middle of the orthographic projection of the first component in the set plane, and the set plane is perpendicular to the thickness direction of the circuit board.

3. The circuit board assembly according to claim 2, wherein: An observation through hole is also provided on the top of the cover, and the observation through hole corresponds to the edge of the first component.

4. The circuit board assembly according to claim 1, wherein: The top of the cover has an outer surface, and a hole-shielding sticker is provided on the outer surface of the top of the cover, and the hole-shielding sticker covers the first through hole.

5. The circuit board assembly according to claim 4, wherein: The hole mask is provided with a slit.

6. The circuit board assembly according to claim 5, wherein: The slit includes a plurality of sub-slits, and one end of the plurality of sub-slits in the length direction intersects.

7. The circuit board assembly according to claim 1, wherein: An underfill is provided between the first component and the circuit board.

8. The circuit board assembly according to claim 1, wherein: The first component is a chip.

9. The circuit board assembly according to claim 7, wherein: A second through hole is also provided on the top of the cover, and the second through hole corresponds to the edge of the first component.

10. The circuit board assembly according to claim 9, wherein: The orthographic projection of the second through hole in a set plane partially overlaps or is separated from the orthographic projection of the first component in the set plane, and the set plane is perpendicular to the thickness direction of the circuit board.

11. The circuit board assembly according to any one of claims 1 to 10, wherein: It also includes a heat-conducting structure, which is arranged between the top of the cover and the first component.

12. The circuit board assembly according to claim 11, wherein: The cover top has an inner surface, the first component has a first surface, the inner surface and the first surface of the cover top are arranged opposite to each other, and the heat conducting structure contacts the inner surface and the first surface of the cover top respectively.

13. The circuit board assembly according to claim 11, wherein: The heat-conducting structure is a heat-conducting gel.

14. The circuit board assembly according to any one of claims 1 to 10, wherein: The cover top has an inner surface, the first component has a first surface, and a distance between the first surface and the inner surface of the cover top in a thickness direction of the circuit board is 0.1 mm to 3 mm.

15. The circuit board assembly according to claim 14, wherein: A distance between the first surface and the inner surface of the cover top in a thickness direction of the circuit board is 0.1 mm, 0.5 mm, 1 mm, 2 mm or 3 mm.

16. The circuit board assembly according to any one of claims 1 to 10, wherein: The aperture of the first through hole is 0.3 mm to 3 mm.

17. The circuit board assembly according to claim 16, wherein: The aperture of the first through hole is: 0.3 mm, 0.5 mm, 1 mm, 1.5 mm or 3 mm.

18. A circuit board assembly, characterized in that: include: circuit boards; A shielding cover is mounted on the circuit board, with an accommodating cavity formed between the shielding cover and the circuit board; a first component, the first component being mounted on the circuit board and located in the accommodating cavity; The shielding cover includes a cover top and a blocking portion, the blocking portion is arranged at a circumferential edge of the cover top, and a heat conducting structure is arranged between the cover top and the first component.

19. The circuit board assembly according to claim 18, wherein: An underfill is provided between the first component and the circuit board.

20. A shielding cover for covering a first component of an electronic device, characterized in that: The shielding cover includes a cover top and a surrounding portion, the surrounding portion is arranged at the circumferential edge of the cover top, and a first through hole is provided on the cover top, the first through hole is arranged opposite to the first component, and the first through hole is used for allowing the heat-conducting structure to pass through so that the heat-conducting structure can be filled into the interior of the shielding cover.

21. The shielding cover according to claim 20, wherein: An observation through hole is also provided on the top of the cover, and the observation through hole is used to correspond to the edge of the first component.

22. The shielding cover according to claim 21, wherein: The aperture of the first through hole is 0.3 mm to 3 mm.

23. An electronic device, characterized in that: The method comprises the circuit board assembly according to any one of claims 1 to 19, or the shielding cover according to any one of claims 20 to 22.

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