Circuit board assembly, electronic equipment and manufacturing method of circuit board assembly

Abstract

The invention provides a circuit board assembly, electronic equipment and a manufacturing method of the circuit board assembly, and relates to the technical field of electronic equipment. The problem that in the manufacturing process of an existing circuit board assembly, an electronic device needs to go through a high-temperature environment for many times, and the electronic device is prone to failure is solved. The circuit board assembly comprises a first circuit board and a frame board. The frame plate comprises a plurality of sub-circuit boards which are sequentially arranged in a stacked mode, every two adjacent sub-circuit boards are fixedly connected, and any two sub-circuit boards are electrically connected. The surface, facing the first circuit board, of the frame plate is a first surface, and a first accommodating space is formed in the first surface; the first circuit board is fixed on the first surface and is electrically connected with the frame plate. The circuit board assembly provided by the invention is applied to the electronic equipment.

Description

Technical Field

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

[0002] The main board inside the electronic device is used to connect various electronic devices to achieve communication between the various electronic devices. As electronic devices are gradually becoming lighter and thinner, the internal space of the electronic device is constantly decreasing. Therefore, the electronic device can also use a circuit board assembly in which a circuit board and a frame board are stacked as a main board to reduce the space occupied inside the electronic device. However, the circuit board and the frame board in the circuit board assembly are fixed by welding, which causes the electronic devices set on the circuit board to be subjected to high temperatures many times, which is easy to affect the performance of the electronic devices and even cause the electronic devices to fail. Summary of the invention

[0003] The embodiments of the present application provide a circuit board assembly, an electronic device, and a method for manufacturing a circuit board assembly, which are used to solve the problem that during the manufacturing process of the circuit board assembly, electronic devices need to experience multiple high-temperature environments, which can easily affect the performance of the electronic devices and even cause the electronic devices to fail.

[0004] To achieve the above objectives, the embodiments of the present application adopt the following technical solutions:

[0005] In a first aspect, a circuit board assembly is provided, the circuit board assembly comprising a first circuit board and a frame board. The frame board comprises a plurality of sub-circuit boards stacked in sequence, two adjacent sub-circuit boards are fixedly connected, and any two sub-circuit boards are electrically connected. The surface of the frame board facing the first circuit board is a first surface, and a first accommodation space is provided on the first surface; the first circuit board is fixed on the first surface and is electrically connected to the frame board.

[0006] The circuit board assembly provided in the first aspect of the present application, because the frame board includes a plurality of sub-circuit boards, and a first storage space is provided on the first surface, that is, the first storage space can be used to set up electronic devices, and the electronic devices can be fixed in the first storage space, that is, the electronic devices can be set up on the frame board. That is, the frame board includes a frame structure that encloses the first storage space and a plate structure for setting up electronic devices, and the frame structure and the plate structure do not need to be fixed by welding. In this way, when the first circuit board is welded to the frame board, the electronic devices on the first circuit board can experience a high temperature environment less than once, which is conducive to reducing the risk of damage to the electronic devices due to the high temperature environment.

[0007] In a possible implementation of the first aspect of the present application, the first accommodation space extends along the stacking direction of the multiple sub-circuit boards and penetrates at least one layer of the sub-circuit boards. Under this structure, it is helpful to reduce the process difficulty of opening the first accommodation space. For example, a corresponding sub-circuit board surface is mounted with a peelable protective glue, and then after the multiple sub-circuit boards are pressed and fixed, the first surface is laser cut (along the edge of the peelable protective glue), and finally the corresponding area that needs to be peeled off can form the first accommodation space.

[0008] In a possible implementation of the first aspect of the present application, a plurality of first accommodating spaces are provided, and the plurality of first accommodating spaces are spaced apart and distributed on the first surface. Under this structure, more electronic devices can be arranged on the frame board, which is conducive to improving the integration of the circuit board assembly.

[0009] In a possible implementation of the first aspect of the present application, the first circuit board covers a portion of the first accommodation space. Under this structure, the area of ​​the first circuit board can be flexibly set according to actual needs, and the electronic devices arranged on the first circuit board can extend into the first accommodation space, which is conducive to reducing the size of the electronic device along the thickness direction, thereby facilitating further improving the integration of the circuit board assembly.

[0010] In a possible implementation of the first aspect of the present application, the surface of the frame plate away from the first circuit board is the second surface, a second accommodation space is provided on the second surface, and the second accommodation space is independent of the first accommodation space; the circuit board assembly also includes a second circuit board, the second circuit board is fixed on the second surface, and is electrically connected to the frame plate. In this way, both sides of the frame plate can be electrically connected to the circuit board, which is conducive to further improving the integration of the circuit board assembly.

[0011] In a possible implementation of the first aspect of the present application, on a plane parallel to the sub-circuit board, a portion of the vertical projection of the first accommodation space overlaps with a portion of the vertical projection of the second accommodation space; and on a plane parallel to the sub-circuit board, the first accommodation space and the second accommodation space whose vertical projections overlap are separated by at least one layer of sub-circuit board. In this way, the spatial layout on the frame board can be made more reasonable, so that more electronic devices can be arranged on the frame board, thereby improving the integration of the circuit board assembly.

[0012] In a possible implementation of the first aspect of the present application, the second storage space extends along the stacking direction of the multiple sub-circuit boards and penetrates at least one layer of the sub-circuit boards. Under this structure, it is helpful to reduce the process difficulty of opening the second storage space. For example, a corresponding sub-circuit board surface is mounted with a peelable protective glue, and then after the multiple sub-circuit boards are pressed and fixed, the second surface is laser cut (along the edge of the peelable protective glue), and finally the corresponding area that needs to be peeled off can form the second storage space.

[0013] In a possible implementation of the first aspect of the present application, a plurality of second accommodating spaces are provided, and the plurality of second accommodating spaces are spaced apart on the second surface. Under this structure, more electronic devices can be arranged on the frame board, which is conducive to improving the integration of the circuit board assembly.

[0014] In a possible implementation of the first aspect of the present application, the second circuit board covers a portion of the second accommodation space. Under this structure, the area of ​​the second circuit board can be flexibly set according to actual needs, and the electronic devices arranged on the second circuit board can extend into the second accommodation space, which is conducive to reducing the size of the electronic device along the thickness direction, thereby facilitating further improving the integration of the circuit board assembly.

[0015] In a possible implementation of the first aspect of the present application, the plurality of sub-circuit boards include a first sub-circuit board, a second sub-circuit board and a third sub-circuit board, the second sub-circuit board is arranged between the first sub-circuit board and the third sub-circuit board, the surface of the first sub-circuit board away from the second sub-circuit board is the first surface, and the surface of the third sub-circuit board away from the second sub-circuit board is the second surface; at least one first accommodation space is arranged on the first surface, and at least one second accommodation space is arranged on the second surface. In this way, electronic devices can be arranged on both side surfaces of the second sub-circuit board, and welding is not required between the second sub-circuit board and the first sub-circuit board, and between the second sub-circuit board and the third sub-circuit board, so that the number of times the electronic devices experience a high temperature environment can be reduced, so as to reduce the risk of damage to the electronic devices due to high temperature.

[0016] In a possible implementation of the first aspect of the present application, the first accommodation space runs through the first sub-circuit board, and the second accommodation space runs through the third sub-circuit board. In this structure, the first accommodation space and the second accommodation space are separated by the second sub-circuit board, that is, both side surfaces of the second sub-circuit board are used to set electronic devices.

[0017] In a possible implementation of the first aspect of the present application, a plurality of second accommodating spaces are provided, and a portion of the plurality of second accommodating spaces penetrates the third sub-circuit board, another portion of the plurality of second accommodating spaces penetrates the second sub-circuit board, and the first accommodating space penetrates the first sub-circuit board; wherein, in a plane parallel to the first surface, the vertical projection of the first accommodating space is misaligned with the vertical projection of the second accommodating space penetrating the second sub-circuit board. Under this structure, the depth dimensions of the second accommodating spaces are different, that is, the depth dimensions of some second accommodating spaces are larger, while the depth dimensions of some second accommodating spaces are smaller. Therefore, electronic devices of different sizes can be arranged on the frame board to improve the scope of application of the frame board.

[0018] In a possible implementation of the first aspect of the present application, the sub-circuit board includes multiple metal layers and multiple dielectric layers, and the multiple metal layers and the multiple dielectric layers are alternately stacked; wherein the first sub-circuit board and the second sub-circuit board each include at least three metal layers, and the third sub-circuit board includes at least two metal layers. In this way, when the three sub-circuit boards are pressed and fixed, on the one hand, it is helpful to alleviate the squeezing force received by the second sub-circuit board located in the middle, thereby reducing the risk of the second sub-circuit board being squeezed and damaged. On the other hand, it is helpful to reduce production costs.

[0019] In a possible implementation of the first aspect of the present application, at least one electronic device is disposed between the first surface of the frame plate and the first circuit board, that is, the electronic device is welded and fixed on the first surface, and the first circuit board is welded and fixed to the electronic device, thereby further improving the integration of the circuit board assembly.

[0020] In a possible implementation of the first aspect of the present application, the first circuit board includes a plurality of circuit board bodies, the plurality of circuit board bodies are stacked and fixedly connected, and two adjacent circuit board bodies are electrically connected; the surface of the first circuit board facing the frame plate is the third surface, a third accommodation space is provided on the third surface, and the third accommodation space is opposite to the first accommodation space. In this way, the first circuit board adopts the same structure as the above-mentioned frame plate, which is conducive to further improving the integration of the circuit board assembly.

[0021] In a second aspect, an electronic device is provided, comprising a display module, a housing and a circuit board assembly. The housing is fixedly connected to the display module. The circuit board assembly is a circuit board assembly as described in any of the above technical solutions, and the circuit board assembly is arranged in the housing.

[0022] The electronic device provided in the second aspect of the present application, because it includes the circuit board assembly described in any of the above technical solutions, can solve the same technical problems and achieve the same technical effects.

[0023] In a possible implementation of the second aspect of the present application, the outer shell includes a middle frame and a back cover, the middle frame is fixedly connected to the display module, the back cover is fixedly connected to the middle frame, and is arranged on a side of the middle frame away from the display module; the back cover has a protruding area protruding in a direction away from the display module; the first accommodating cavity of the circuit board assembly is arranged corresponding to the protruding area.

[0024] In a third aspect, a method for manufacturing a circuit board assembly is provided, comprising fixing and pressing a plurality of sub-circuit boards to form a frame board blank, wherein the frame board blank has a first surface, a first accommodation space is opened on the first surface to form a frame board, and a first circuit board is welded on the first surface.

[0025] The manufacturing method of the circuit board assembly provided in the third aspect of the present application can reduce one welding fixation (i.e., between the above-mentioned frame structure and the board structure) by first fixing and pressing multiple sub-circuit boards and then opening a first accommodating space on the first surface, thereby reducing the number of times the electronic device experiences a high temperature environment, which is beneficial to reducing the risk of damage to the electronic device due to a high temperature environment.

[0026] In a possible implementation of the third aspect of the present application, the frame plate blank further has a second surface, the second surface is arranged opposite to the first surface, and after the first accommodation space is opened on the first surface, the manufacturing method further includes opening a second accommodation space on the second surface, and the second accommodation space is independent of the first accommodation space. In this way, the number of electronic devices that can be arranged on the frame plate can be further increased, which is conducive to improving the integration of the circuit board assembly.

[0027] In a possible implementation of the third aspect of the present application, after the first circuit board is welded on the first surface, the manufacturing method further includes welding the second circuit board on the second surface. Under this structure, it is beneficial to further improve the integration of the circuit board assembly.

[0028] In a possible implementation of the third aspect of the present application, the plurality of sub-circuit boards include a first sub-circuit board and a second sub-circuit board, the first sub-circuit board and the second sub-circuit board are stacked, the surface of the first sub-circuit board away from the second sub-circuit board is the first surface, and the surface of the second sub-circuit board close to the first sub-circuit board has a first area and a second area. Before fixing and pressing the plurality of sub-circuit boards, the manufacturing method also includes setting an adhesive layer on the first area and setting a peeling film layer on the second area. The method of opening a first accommodation space on the first surface includes laser cutting the first sub-circuit board along the edge of the second area on the first surface; removing the portion of the first sub-circuit board that overlaps with the second area and the peeling film layer to form a first accommodation space. In this way, by setting a peeling film layer (for example, a peelable protective glue) in the second area, it is convenient to remove the material in the corresponding area after laser cutting to form the first accommodation space.

[0029] Furthermore, the second accommodation space may also adopt this method, that is, a release film layer is provided on the surface of the second sub-circuit board close to the third sub-circuit board, and then laser cutting is performed to remove the material in the corresponding area to form the second accommodation space.

[0030] In a possible implementation of the third aspect of the present application, the method of opening the first accommodation space on the first surface includes performing a controlled depth milling process on the first surface to form the first accommodation space. Under this structure, the controlled depth milling process can be used to mill the first accommodation space with a larger depth. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A structural diagram of an electronic device provided in an embodiment of the present application;

[0032] Figure 2 An exploded diagram of an electronic device provided in an embodiment of the present application;

[0033] Figure 3 A structural diagram of a circuit board assembly provided for related art;

[0034] Figure 4 A structural diagram of another circuit board assembly provided for related technology;

[0035] Figure 5 A structural diagram of another circuit board assembly provided for related technology;

[0036] Figure 6 for Figure 5 A flow chart for the production of a circuit board assembly is provided;

[0037] Figure 7 A structural diagram of a circuit board assembly provided in an embodiment of the present application;

[0038] Figure 8 for Figure 7 A structural diagram of a frame board in a provided circuit board assembly;

[0039] Fig. 9 A structural diagram of another frame plate provided in an embodiment of the present application;

[0040] Fig.10 A structural diagram of another circuit board assembly provided in an embodiment of the present application;

[0041] Fig.11 for Fig.10 A structural diagram of a frame board in a provided circuit board assembly;

[0042] Fig.12 A structural diagram of another frame plate provided in an embodiment of the present application;

[0043] Fig.13 A structural diagram of another circuit board assembly provided in an embodiment of the present application;

[0044] Fig.14 for Fig.13 A structural diagram of a first surface of a frame board in a provided circuit board assembly;

[0045] Fig.15 A cross-sectional view of a partial structure of an electronic device provided in an embodiment of the present application;

[0046] Fig.16 A structural diagram of another circuit board assembly provided in an embodiment of the present application;

[0047] Fig.17 A structural diagram of another circuit board assembly provided in an embodiment of the present application;

[0048] Fig.18 A flow chart of a method for manufacturing a circuit board assembly provided in an embodiment of the present application;

[0049] Fig.19 A structural diagram of a sub-circuit board (first sub-circuit board) provided in an embodiment of the present application;

[0050] Fig. 20 A structural diagram of a sub-circuit board (second sub-circuit board) provided in an embodiment of the present application;

[0051] Fig.21 A structural diagram of a sub-circuit board (third sub-circuit board) provided in an embodiment of the present application;

[0052] Fig. 22 for Fig.19 Provides the first daughter board and Fig. 20 A structural diagram of the second sub-circuit board after being pressed and fixed;

[0053] Fig.23 for Fig. 22 A structural diagram of the first sub-circuit board and the second sub-circuit board after lamination and before lamination of the third sub-circuit board is provided;

[0054] Fig.24 for Fig.23 A structural diagram of a frame plate blank formed by laminating the first sub-circuit board, the second sub-circuit board and the third sub-circuit board provided;

[0055] Fig.25 A structural diagram of the first sub-circuit board, the second sub-circuit board and the third sub-circuit board after being pressed together provided in an embodiment of the present application;

[0056] Fig.26 for Fig.25 A structural diagram of another frame plate blank provided with through holes opened on the first sub-circuit board, the second sub-circuit board and the third sub-circuit board after lamination;

[0057] Fig. 27 A structural diagram of a second sub-circuit board (the surface facing the first sub-circuit board) provided in an embodiment of the present application;

[0058] Fig.28 A structural diagram of the second sub-circuit board (the surface facing the third sub-circuit board) provided in an embodiment of the present application;

[0059] Fig.29 A structural diagram of another frame plate blank provided in an embodiment of the present application;

[0060] Fig.30 for Fig.29 A cross-sectional view of the frame plate blank provided for laser cutting;

[0061] Fig.31 A schematic diagram of the structure of spraying solder paste on a frame plate provided in an embodiment of the present application;

[0062] Fig.32 for Fig.31 A process flow chart of manufacturing a circuit board assembly formed by a frame board, a first sub-circuit board and a second sub-circuit board is provided;

[0063] Fig.33 A structural diagram of the first sub-circuit board (the surface facing the second sub-circuit board) provided in an embodiment of the present application;

[0064] Fig.34 A structural diagram of another second circuit board (the surface facing the first sub-circuit board) provided in an embodiment of the present application;

[0065] Fig.35 for Fig.33 A first sub-circuit board is provided, Fig.34 A cross-sectional view of the second sub-circuit board and the third sub-circuit board after being pressed and fixed;

[0066] Fig.36 A schematic diagram of a partial structure of spraying solder paste on a frame plate provided in an embodiment of the present application;

[0067] Fig.37 A structural diagram of a metal layer in a frame plate blank provided in an embodiment of the present application;

[0068] Fig.38 A process flow chart of the frame plate manufacturing process provided in the embodiment of the present application;

[0069] Fig.39 A structural diagram of a circuit board assembly and internal metal circuits provided in an embodiment of the present application.

[0070] Figure numerals: 01-electronic device; 10-display module; 11-translucent cover plate; 12-display screen; 20-housing; 21-back cover; 21a-protruding area; 22-frame; 23-middle plate; 30-main board; 40-electronic device; 50-circuit board assembly; 51-AP board; 52-RF board; 52a-first RF board; 52b-second RF board; 52c-third RF board; 100-frame board; 100a-first frame board; 100b-second frame board; 100c-third frame board; 101-frame board blank; 110-sub-circuit board; 11 1-first sub-circuit board; 111a-first surface; 112-second sub-circuit board; 112a-first area; 112b-second area; 113-third sub-circuit board; 113a-second surface; 114-metal layer; 115-dielectric layer; 116-conducting hole; 120-first storage space; 130-second storage space; 140-adhesive layer; 150-peeling film layer; 200-first circuit board; 210-first circuit board body; 210a-third surface; 220-second circuit board body; 230-third storage space; 300-second circuit board. DETAILED DESCRIPTION

[0071] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0072] In the following, the terms "first", "second", etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features.

[0073] In addition, in the present application, directional terms such as "upper" and "lower" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they can change accordingly according to the changes in the orientation of the components in the drawings.

[0074] In the present application, unless otherwise clearly specified and limited, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0075] The embodiment of the present application provides an electronic device. Specifically, the electronic device may be a portable electronic device or other types of electronic devices. For example, the electronic device may be a mobile phone, a tablet personal computer, a laptop computer, a personal digital assistant (PDA), a monitor, a camera, a personal computer, a notebook computer, a wearable device, etc. For the convenience of explanation, the following examples are all taken as an example of the electronic device being a mobile phone.

[0076] See also Figure 1 and Figure 2 , Figure 1 This is a structural diagram of an electronic device 01 provided in an embodiment of the present application. Figure 2 The exploded view of the electronic device 01 provided in the embodiment of the present application. As can be seen from the above, in the present embodiment, the electronic device 01 is a mobile phone, and the electronic device 01 can be in an approximately rectangular plate-shaped structure. The electronic device 01 can include a display module 10, a housing 20, a mainboard 30 and an electronic device 40. It can be understood that, Figure 1 and Figure 2 Only some components of the electronic device 01 are schematically shown, and the actual shapes, sizes, positions and structures of these components are not subject to the present invention. Figure 1 and Figure 2 restrictions.

[0077] To facilitate the description of the following embodiments, an XYZ coordinate system is established. The width direction of the electronic device 01 is defined as the X-axis direction, the length direction of the electronic device 01 is defined as the Y-axis direction, and the thickness direction of the electronic device 01 is defined as the Z-axis direction. The XYZ coordinate system can be flexibly set according to actual needs. The embodiments of the present application only provide an example and cannot be considered as a special limitation to the present application.

[0078] The above-mentioned display module 10 is used to display images, videos, etc. The display module 10 may include a light-transmitting cover plate 11 and a display screen 12 (English name: panel, also called a display panel), and the light-transmitting cover plate 11 and the display screen 12 are stacked. The material of the light-transmitting cover plate 11 includes but is not limited to glass. For example, the light-transmitting cover plate 11 can adopt an ordinary light-transmitting cover plate 11, which is used to protect the display screen 12 to prevent the display screen 12 from being damaged due to external force, and can play a dust-proof role. Alternatively, the light-transmitting cover plate 11 can also adopt a light-transmitting cover plate 11 with a touch function, so that the electronic device 01 has a touch function, which makes it more convenient for users to use. Therefore, the present application does not specifically limit the specific material of the light-transmitting cover plate 11.

[0079] In addition, the display screen 12 may be a flexible display screen 12 or a rigid display screen 12. For example, the display screen 12 may be an organic light-emitting diode (OLED) display screen 12, an active-matrix organic light-emitting diode or an active-matrix organic light-emitting diode (AMOLED) display screen 12, a mini organic light-emitting diode display screen 12, a micro organic light-emitting diode display screen 12, a micro organic light-emitting diode display screen 12, a quantum dot light emitting diode (QLED) display screen 12, or a liquid crystal display 12 (LCD).

[0080] The housing 20 is used to protect the electronic device 40 inside the electronic device 01. The housing 20 may include a back cover 21 and a frame 22. The back cover 21 is located on the side of the display screen 12 away from the light-transmitting cover plate 11, and is stacked with the light-transmitting cover plate 11 and the display screen 12. The frame 22 is located between the light-transmitting cover plate 11 and the back cover 21. The frame 22 is fixed to the back cover 21. For example, the frame 22 may be fixed to the back cover 21 by bonding, threading, welding, snapping, etc.; or, the frame 22 may also be an integrally formed structure with the back cover 21, that is, the frame 22 and the back cover 21 form a structural component as a whole. The light-transmitting cover plate 11 may be fixed to the frame 22 by gluing, so that the light-transmitting cover plate 11, the back cover 21 and the frame 22 enclose a receiving cavity inside the electronic device 01, and the motherboard 30 and the electronic device 40 are both arranged in the receiving cavity.

[0081] In some embodiments, the housing 20 may further include a middle plate 23, which is disposed in the accommodating cavity, and the middle plate 23 is located on the side of the display screen 12 away from the light-transmitting cover plate 11. The middle plate 23 is fixedly connected to the frame 22 to form the middle frame of the electronic device 01. For example, the middle plate 23 and the frame 22 may be fixedly connected by gluing, threading, welding, snapping, etc.; or, the middle plate 23 and the frame 22 may also be an integrally formed structure, that is, the middle plate 23 and the frame 22 form a structural component as a whole. The middle plate 23 divides the accommodating cavity into two independent spaces, one of which is located between the light-transmitting cover plate 11 and the middle plate 23, and the display screen 12 is located in the space. The other space is located between the middle plate 23 and the back cover 21, and the main board 30 is located in the space.

[0082] The mainboard 30 is used to set the electronic devices 40 inside the electronic device 01 and realize the electrical connection between the electronic devices 40. The mainboard 30 can be fixed on the middle plate 23 by gluing, threading, welding, clamping, etc. Therefore, the fixing method of the mainboard 30 is not specifically limited in this application.

[0083] The electronic device 40 is used to implement various functions of the electronic device 01. For example, the electronic device 40 may be a control chip (such as a system on chip, SOC), a graphics processing unit (GPU), a universal flash storage (UFS), a camera module, a flash module, a capacitor, a resistor, an inductor, etc. Figure 2 The electronic device 40 shown is a camera module.

[0084] In some examples, the main board 30 may be a PCB board, and the electronic devices 40 are distributed on the main board 30. Due to the trend of electronic devices 01 becoming increasingly thinner, the internal space of the housing 20 of the electronic device 01 (i.e., the accommodating cavity) is continuously reduced, thus limiting the area of ​​the main board 30 and the number of electronic devices 40 distributed on the main board 30.

[0085] In order to make the distribution of the electronic devices 40 inside the electronic device 01 more reasonable. The main board 30 can adopt a stacked circuit board structure to form a circuit board assembly 50, see Figure 3 , Figure 3A structural diagram of a circuit board assembly 50 is provided for related art. The circuit board assembly 50 may be composed of a frame board 100 and a circuit board stacked together. Exemplarily, the circuit board may be a radio frequency board (RF PCB), or an application processor board (AP PCB).

[0086] In some embodiments, the circuit board assembly 50 may include a frame board 100 and two circuit boards (e.g., an AP board 51 and an RF board 52), the frame board 100 being disposed between the AP board 51 and the RF board 52, that is, a cavity is formed between the AP board 51, the RF board 52 and the frame board 100, and the electronic device 40 can be disposed in the cavity. In this way, electronic devices 40 can be disposed on both side surfaces of the AP board 51 and the RF board 52 (i.e., the surface facing the cavity and the surface facing the outside of the cavity), so that a plurality of electronic devices 40 can be distributed along the thickness direction (i.e., the Z direction) of the electronic device 01, thereby reducing the area of ​​the circuit board (the area in the XY plane), that is, reducing the Figure 2 The space occupied by the mainboard 30 inside the housing 20 in the XY plane is shown.

[0087] On this basis, in order to further improve the integration of the circuit board assembly 50, the circuit board assembly 50 may include multiple frame boards 100 and multiple circuit boards, the circuit boards are stacked in multiple layers, and frame boards 100 are arranged between two adjacent layers of circuit boards. In addition, multiple frame boards 100 may be arranged in any layer of the multiple layers of frame boards 100.

[0088] For example, see Figure 4 , Figure 4 A structural diagram of another circuit board assembly 50 provided for related art. The circuit board assembly 50 may include an AP board 51, multiple RF boards 52, and multiple frame boards 100. Specifically, a first frame board 100a is welded and fixed to the AP board 51, a first RF board 52a is welded and fixed to the side of the first frame board 100a away from the AP board 51, a second frame board 100b and a third frame board 100c are welded and fixed to the side of the first RF board 52a away from the first frame board 100a, a second RF board 52b is welded and fixed to the side of the second frame board 100b away from the first RF board 52a, and a third RF board 52c is welded and fixed to the side of the third frame board 100c away from the first RF board 52a.

[0089] Alternatively, see Figure 5 and Figure 6 , Figure 5 A structural diagram of another circuit board assembly 50 provided in the related art, Figure 6 for Figure 5A manufacturing flow chart of a circuit board assembly 50 is provided. In the circuit board assembly 50, a first frame plate 100a and a second frame plate 100b are both welded and fixed to an AP board 51, a first RF board 52a is welded and fixed to a side of the first frame plate 100a away from the AP board 51, a second RF board 52b is welded and fixed to a side of the second frame plate 100b away from the AP board 51, a third frame plate 100c is welded and fixed to a side of the second RF board 52b away from the first frame plate 100a, and a third RF board 52c is welded and fixed to a side of the third frame plate 100c away from the second RF board 52b.

[0090] In addition, the above-mentioned electronic devices 40 are arranged on the surfaces of both sides of the AP board 51, the first RF board 52a, the second RF board 52b and the third RF board 52c, so as to further improve the integration of the circuit board assembly 50, save the internal space of the housing 20 of the electronic device 40, and facilitate the lightweight and thinning of the electronic device 01.

[0091] However, during the manufacturing process of the above-mentioned circuit board assembly 50, some electronic devices 40 will experience high temperature environments during multiple welding. Figure 5 During the manufacturing process of the circuit board assembly 50 shown, when the electronic device 40 is welded on the third RF board 52c, the electronic device 40 experiences the first high temperature environment. When the third RF board 52c is welded to the third frame board 100c, the electronic device 40 on the third RF board 52c experiences the second high temperature environment. When the third frame board 100c is welded to the second RF board 52b, the electronic device 40 on the third RF board 52c experiences the third high temperature environment. In the subsequent welding process, the electronic device 40 on the third RF board 52c also needs to experience a relatively high temperature environment.

[0092] Therefore, the electronic device 40 on the third RF board 52c needs to experience high temperature environments at least three times, which makes the electronic device 40 easily damaged or even burned, and thus the circuit board assembly 50 is scrapped. Moreover, if more frame boards 100 and circuit boards (including AP boards 51 and RF boards 52) are stacked, the electronic device 40 may need to experience high temperature environments more times, and the probability of damage will be greater, which will limit the number of stacked circuit boards in the circuit board assembly 50.

[0093] To solve the above technical problems, please refer to Figure 7 and Figure 8 , Figure 7 A structural diagram of a circuit board assembly 50 provided in an embodiment of the present application is shown in FIG. Figure 8 for Figure 7A structural diagram of a frame plate 100 in a circuit board assembly 50 is provided. The circuit board assembly 50 may include a first circuit board 200 and a frame plate 100, wherein the frame plate 100 includes a plurality of sub-circuit boards 110 stacked in sequence, wherein two adjacent sub-circuit boards 110 are fixedly connected, and any two adjacent sub-circuit boards 110 are electrically connected; the surface of the frame plate 100 facing the first circuit board 200 is a first surface 111a, i.e., the surface of a sub-circuit board 110 adjacent to the first circuit board 200 facing the first circuit board 200 is the first surface 111a, and a first accommodation space 120 is provided on the first surface 111a. The first circuit board 200 is fixed on the first surface 111a and is electrically connected to the frame plate 100.

[0094] Exemplarily, the frame plate 100 may include two sub-circuit boards 110, which are a first sub-circuit board 111 and a second sub-circuit board 112 stacked in sequence. The first sub-circuit board 111 is disposed adjacent to the first circuit board 200, that is, the surface of the first sub-circuit board 111 facing the first circuit board 200 is the first surface 111a. The first accommodation space 120 may penetrate the first sub-circuit board 111 and extend to the second sub-circuit board 112.

[0095] Please continue reading Figure 7 and Figure 8 , the first accommodation space 120 can be used to accommodate the electronic device 40. For example, the electronic device 40 disposed on the first circuit board 200 can extend into the first accommodation space 120, and the electronic device 40 disposed in the first accommodation space 120 and fixed on the second sub-circuit board 112. Since the frame board 100 and the first circuit board 200 are electrically connected, the electronic device 40 disposed on the first circuit board 200 and the electronic device 40 disposed on the frame board 100 (i.e., the second sub-circuit board 112) can be electrically connected.

[0096] It is understandable that in addition to the first accommodating space 120, electronic devices 40 can also be set in other areas of the frame plate 100. For example, the surface of the second sub-circuit board 112 away from the first sub-circuit board 111 can also be used to set electronic devices 40, which is beneficial to improve the integration of the circuit board assembly 50.

[0097] For some examples, see Fig. 9 , Fig. 9 This is a structural diagram of another frame plate 100 provided in an embodiment of the present application. The first accommodation space 120 may be provided in plurality, and the plurality of first accommodation spaces 120 are distributed at intervals on the first surface 111 a. Each first accommodation space 120 can be provided with an electronic device 40 .

[0098] Furthermore, the first circuit board 200 may be provided in plurality, and each first circuit board 200 covers at least one first accommodation space 120. For example, three first accommodation spaces 120 may be provided, two first circuit boards 200 may be provided, and each first circuit board 200 covers one first accommodation space 120, that is, two first accommodation spaces 120 are covered with the first circuit board 200, and one second accommodation space 130 is not covered with the first circuit board 200.

[0099] In addition, the first circuit board 200 covers the first accommodation space 120, and the first circuit board 200 may completely cover one or more first accommodation spaces 120, so that the first accommodation space 120 forms a closed space. Alternatively, the first circuit board 200 only covers a part of the first accommodation space 120, that is, the first accommodation space 120 does not form a closed space. Alternatively, part of the first accommodation space 120 forms a closed space, and part of the first accommodation space 120 does not form a closed space. Therefore, this application does not make any special limitation on this.

[0100] Based on this, the frame board 100 provided in the embodiment of the present application is composed of a plurality of sub-circuit boards 110 stacked and fixed to each other, and electrically connected to each other. Then, a first receiving space 120 is opened on the first surface 111a, that is, the frame board 100 includes the first sub-circuit board 111 (equivalent to Figure 3 The frame board 100 shown in the figure) and the second sub-circuit board 112 (equivalent to Figure 3 The first sub-circuit board 111 and the second sub-circuit board 112 are fixedly connected to form the overall structure of the frame board 100, that is, the first sub-circuit board 111 and the second sub-circuit board 112 form a structural component as a whole. Figure 3 The circuit board assembly 50 shown in the figure can, during the manufacturing process, omit the step of welding and fixing the first sub-circuit board 111 and the second sub-circuit board 112, that is, the electronic device 40 on the first circuit board 200 can experience the high temperature welding environment once less, thereby helping to reduce the probability of damage to the electronic device 40 due to experiencing the high temperature environment.

[0101] On this basis, see Fig.10 and Fig.11 , Fig.10 A structural diagram of another circuit board assembly 50 provided in an embodiment of the present application is shown in FIG. Fig.11 for Fig.10A structural diagram of the frame plate 100 in the circuit board assembly 50 is provided. The circuit board assembly 50 may also include a second circuit board 300. The surface of the frame plate 100 away from the first circuit board 200 is the second surface 113a, that is, the first surface 111a and the second surface 113a are arranged opposite to each other. A second accommodating space 130 is provided on the second surface 113a, and the second accommodating space 130 is independent of the first accommodating space 120, that is, the two are not connected to each other. The second circuit board 300 is fixed on the second surface 113a and is electrically connected to the frame plate 100.

[0102] Exemplarily, the frame plate 100 may include three sub-circuit boards 110, which are a first sub-circuit board 111, a second sub-circuit board 112, and a third sub-circuit board 113 stacked in sequence. The first sub-circuit board 111 is disposed adjacent to the first circuit board 200, that is, the surface of the first sub-circuit board 111 facing the first circuit board 200 is the first surface 111a. A plurality of first accommodation spaces 120 may be disposed on the first surface 111a, and the first accommodation spaces 120 may penetrate the first sub-circuit board 111 and extend to the second sub-circuit board 112. The third sub-circuit board 113 is disposed adjacent to the second circuit board 300, that is, the surface of the third sub-circuit board 113 facing the second circuit board 300 is the second surface 113a. The second accommodation space 130 may penetrate the third sub-circuit board 113 and extend to the second sub-circuit board 112. That is, the second sub-circuit board 112 separates the first accommodation space 120 from the second accommodation space 130.

[0103] In this way, the first accommodation space 120 and the second accommodation space 130 can both be used to accommodate the electronic device 40, that is, the electronic device 40 can be set on both sides of the second sub-circuit board 112. In addition, the first circuit board 200 and the second circuit board 300 can both be used to set electrical devices, which is conducive to improving the integration of the circuit board assembly 50.

[0104] In addition, the frame board 100 includes a second sub-circuit board 112 (equivalent to Figure 4 The first RF board 52a shown in the figure and the first sub-circuit board 111 (equivalent to the first sub-circuit board 111) disposed on both sides of the second sub-circuit board 112 and having a plurality of first accommodation spaces 120 are opened. Figure 4 The second frame plate 100b shown in the figure and the third sub-circuit board 113 (equivalent to Figure 4 The first frame plate 100a shown in the figure). Since the first sub-circuit board 111, the second sub-circuit board 112 and the third sub-circuit board 113 are fixedly connected, the overall structure of the frame plate 100 is formed, that is, the first sub-circuit board 111, the second sub-circuit board 112 and the third sub-circuit board 113 form an integral structure. Figure 4The circuit board assembly 50 shown in the embodiment of the present application can omit the step of welding and fixing the second sub-circuit board 112 to the first sub-circuit board 111 and the third sub-circuit board 113 on both sides during the manufacturing process, that is, the electronic devices 40 on the first circuit board 200 and the electronic devices 40 on the second circuit board 300 can reduce the number of times they experience a high-temperature welding environment, which is beneficial to reduce the probability of damage to the electronic devices 40 due to high temperature.

[0105] Please continue reading Fig.10 and Fig.11 , the second accommodation space 130 can be used to accommodate the electronic device 40. For example, the electronic device 40 disposed on the second circuit board 300 can extend into the second accommodation space 120, and the electronic device 40 disposed in the second accommodation space 120 and fixed on the second sub-circuit board 112. Since the frame board 100 and the second circuit board 300 are electrically connected, the electronic device 40 disposed on the second circuit board 300 and the electronic device 40 disposed on the frame board 100 (i.e., the second sub-circuit board 112) can be electrically connected. At the same time, it can be electrically connected to the electronic device 40 disposed on the first circuit board 200, which is conducive to further improving the integration of the circuit board assembly.

[0106] For some examples, see Fig.12 , Fig.12 This is a structural diagram of another frame plate 100 provided in an embodiment of the present application. The second accommodation space 130 may be provided in plurality, and each of the plurality of second accommodation spaces 130 may accommodate an electronic device 40. At the same time, the second circuit board 300 may be provided in plurality.

[0107] Furthermore, the second circuit board 300 covers the second accommodation space 130, which may be that the second circuit board 300 completely covers one or more second accommodation spaces 130, that is, the second accommodation spaces 130 form a closed space. Alternatively, the second circuit board 300 only covers a portion of the second accommodation space 130, and the second accommodation space 130 does not form a closed space. Alternatively, part of the second accommodation space 130 forms a closed space, and part of the second accommodation space 130 does not form a closed space. Therefore, this application does not specifically limit this.

[0108] In addition, the number of the second accommodating spaces 130 and the number of the first accommodating spaces 120, as well as the number of the second circuit boards 300 and the number of the first circuit boards 200, can be the same or different, and their specific numbers can be flexibly set according to actual needs. Therefore, the embodiments of the present application do not specifically limit this.

[0109] To further improve the integration of the circuit board assembly 50 provided in the embodiment of the present application. In the circuit board assembly 50, at least one electronic device may be disposed between the frame plate 100 and the first circuit board 200, and between the frame plate 100 and the second circuit board 300. That is, the electronic device 40 may be disposed on the first surface 111a and the second surface 113a of the frame plate 100, and the first circuit board 200 or the second circuit board 300 may be disposed on the other side of the electronic device 40.

[0110] For example, see Fig.13 and Fig.14 , Fig.13 A structural diagram of another circuit board assembly 50 provided in an embodiment of the present application is shown in FIG. Fig.14 for Fig.13 A structural diagram of the first surface 111a of the frame board 100 in the circuit board assembly 50 is provided. A plurality of electronic devices 40 are arranged on the first surface 111a, and a first circuit board 200 is welded and fixed to one side of the plurality of electronic devices 40 away from the first surface 111a.

[0111] Furthermore, the plurality of electronic devices 40 may be distributed at equal intervals along one direction on the first surface 111a. Alternatively, the plurality of electronic devices 40 may be distributed around a first accommodation space 120. Alternatively, the plurality of electronic devices 40 may be distributed at different positions in an irregular manner according to actual needs. Therefore, the present application does not specifically limit the specific distribution of the electronic devices 40 on the first surface 111a.

[0112] To summarize, the circuit board assembly 50 provided in the embodiment of the present application adopts a frame plate 100 formed by multiple sub-circuit boards 110 (namely, the first sub-circuit board 111, the second sub-circuit board 112 and the third sub-circuit board 113 mentioned above), and the frame plate 100 has a first accommodating space 120 and a second accommodating space 130, that is, electronic devices 40 can be mounted on both side surfaces of the second sub-circuit board 112 in the frame plate 100, which is beneficial to improving the integration of the circuit board assembly 50.

[0113] Furthermore, since the first sub-circuit board 111, the second sub-circuit board 112 and the third sub-circuit board 113 form an integral structure, no additional welding fixation is required between them, that is, no pad structure is required between the first sub-circuit board 111 and the second sub-circuit board 112 and between the second sub-circuit board 112 and the third sub-circuit board 113, which is beneficial to reducing the size of the frame plate 100 along the thickness direction (Z-axis direction) of the electronic device 01, and further beneficial to reducing the size of the circuit board assembly 50 along the thickness direction of the electronic device 01, so as to reduce the space occupied in the housing 20 of the electronic device 01.

[0114] For example, see Fig.15 , Fig.15 This is a cross-sectional view of a partial structure of an electronic device 01 provided in an embodiment of the present application. A protruding area 21a may be provided on the back cover 21 of the electronic device 01, and the protruding area 21a is used to form an appearance decoration for the camera module. That is, along the thickness direction (Z-axis direction) of the electronic device 01, the distance between the protruding area 21a and the middle plate 23 is greater than the distance between other areas on the back cover 21 and the middle plate 23.

[0115] Compared with the circuit board assembly 50 provided by the related art, the circuit board assembly 50 provided by the embodiment of the present application can reduce the size of the circuit board assembly 50 along the thickness direction (Z-axis direction) of the electronic device 01 because the welding fixing structure is reduced in the frame plate 100. That is, at the position corresponding to the protruding area 21a ( Fig.15 As shown in the dotted box A area, the circuit board assembly 50 provided in the embodiment of the present application can stack more circuit boards, so that more electronic devices 40 can be integrated, which is beneficial to improve the integration of the circuit board assembly 50 to save space inside the electronic device 01.

[0116] In other embodiments, the sizes of different electronic devices 40 may be different (for example, the size of the electronic device 40 along the thickness direction of the electronic device 01, i.e., the size in the Z-axis direction). In order to allow the first accommodation space 120 and the second accommodation space 130 to accommodate larger electronic devices 40, the depth size of the first accommodation space 120 or the second accommodation space 130 provided in the embodiment of the present application along the thickness direction (Z-axis direction) of the electronic device 01 may also be changed according to actual needs.

[0117] For example, see Fig.16 , Fig.16 This is a structural diagram of another circuit board assembly 50 provided in an embodiment of the present application. The frame board 100 in the circuit board assembly 50 includes the first sub-circuit board 111, the second sub-circuit board 112 and the third sub-circuit board 113. Only one first accommodation space 120 is provided on the first surface 111a, and the first accommodation space 120 can only pass through the first sub-circuit board 111. Two second accommodation spaces 130 are provided on the second surface 113a, namely the second accommodation space 130a and the second accommodation space 130b.

[0118] The second accommodation space 130a penetrates the third sub-circuit board 113 and the second sub-circuit board 112, and the second accommodation space 130b only penetrates the third sub-circuit board 113. In addition, in a plane parallel to the first surface 111a, the vertical projection of the second accommodation space 130a penetrating the second sub-circuit board 112 and the vertical projection of the first accommodation space 120 are mutually offset.

[0119] At the same time, in a plane parallel to the first surface 111a, the vertical projection of the first accommodation space 120 at least partially overlaps with the vertical projection of the second accommodation space 130b that only passes through the third sub-circuit board 113. That is, the first accommodation space 120 and the second accommodation space 130b are separated by the second sub-circuit board 112.

[0120] Based on this, please continue to refer to Fig.16 In the frame plate 100, the depth dimension of the first accommodating space 120 is the thickness of the first sub-circuit board 111, the depth dimension of the second accommodating space 130a is the sum of the thickness of the second sub-circuit board 112 and the third sub-circuit board 113, and the depth dimension of the third accommodating space 230b is the thickness of the third sub-circuit board 113. In this way, the electronic devices 40 that can be accommodated in the first accommodating space 120 and the second accommodating space 130b can be relatively small in the thickness direction of the electronic device 01. The electronic devices 40 that can be accommodated in the second accommodating space 130a can be relatively large in the thickness direction of the electronic device 01. Therefore, electronic devices 40 of different sizes can be arranged on the circuit board assembly 50, which is conducive to improving the application range of the circuit board assembly 50.

[0121] It should be noted that in the above embodiment, the frame plate 100 includes three stacked sub-circuit boards 110 as an example. In other possible embodiments, the frame plate 100 may also include more stacked sub-circuit boards 110, for example, four-layer sub-circuit boards 110, five-layer sub-circuit boards 110 or six-layer sub-circuit boards 110. In this case, the size of the first accommodating space 120 and the second accommodating space 130 along the thickness direction of the electronic device 01 can be increased according to the increase in the number of sub-circuit boards 110, which can be flexibly changed according to actual use and design needs. Therefore, this application does not make any special restrictions on this.

[0122] In addition, the relatively small or large size along the thickness direction of the electronic device 01 means that, in comparison between two first accommodating spaces 120 of different sizes, two second accommodating spaces 130 of different sizes, or one first accommodating space 120 and one second accommodating space 130, one size is relatively large and the other size is relatively small. For example, between the second accommodating space 130a and the second accommodating space 130b, since the second accommodating space 130a penetrates the third sub-circuit board 113 and the second sub-circuit board 112, while the second accommodating space 130b only penetrates the third sub-circuit board 113. Therefore, along the thickness direction of the electronic device 01, the depth dimension of the second accommodating space 130a is relatively large, while the depth dimension of the second accommodating space 130b is relatively small.

[0123] On this basis, see Fig.17 , Fig.17A structural diagram of another circuit board assembly 50 provided in an embodiment of the present application. The first circuit board 200 in the circuit board assembly 50 may include a plurality of circuit board bodies, which are stacked and fixedly connected, and two adjacent circuit board bodies are electrically connected. The surface of the first circuit board 200 facing the frame plate 100 is the third surface 210a, and a third accommodating space 230 is provided on the third surface 210a, and the third accommodating space 230 is opposite to the above-mentioned first accommodating space 120. That is, the first circuit board 200 also adopts the structure of the above-mentioned frame plate 100 to further improve the integration of the circuit board assembly 50.

[0124] Exemplarily, the first circuit board 200 may include two circuit board bodies, namely a first circuit board body 210 and a second circuit board body 220. The first circuit board body 210 is arranged adjacent to the frame plate 100, that is, the surface of the first circuit board body 210 facing the frame plate 100 is the third surface 210a, and the third surface 210a is welded and fixed to the first surface 111a of the frame plate 100, that is, the first circuit board 200 is snap-fitted and fixed on the first surface 111a of the frame plate 100 so that the first accommodating space 120 is opposite to the third accommodating space 230, so that the first accommodating space 120 and the third accommodating space 230 together form a cavity.

[0125] In this way, since the cavity is formed by the first accommodation space 120 and the third accommodation space 230, the size of the cavity along the thickness direction (Z-axis direction) of the electronic device 01 is relatively large, so that a larger electronic device 40 can be accommodated. In addition, the electronic device 40 disposed on the first circuit board 200 still does not need to experience multiple high-temperature environments, and the risk of damage to the electronic device 40 due to high temperature will not be increased.

[0126] In addition, since the above cavity is formed by the first accommodation space 120 and the third accommodation space 230, during the production and processing stage, a relatively small third accommodation space 230 can be made on the first circuit board 200, and a relatively small first accommodation space 120 can be made on the frame board 100. When the two are buckled together, a relatively large cavity can be formed along the thickness direction of the electronic device 01, which is conducive to reducing the difficulty of production and processing.

[0127] It is understandable that, since the above-mentioned first circuit board 200 can be provided with one or more, when there are multiple first circuit boards 200, a part of the multiple first circuit boards 200 may adopt the structure composed of the above-mentioned multiple circuit board bodies (i.e., the first circuit board 200 is provided with the third accommodation space 230), and the other first circuit boards 200 still adopt the conventional structure. Alternatively, all the multiple first circuit boards 200 may adopt the structure composed of the above-mentioned multiple circuit board bodies.

[0128] Furthermore, the second circuit board 300 may also adopt a structure composed of a plurality of circuit board bodies, that is, the same structure as the first circuit board 200. That is, the specific structures of the first circuit board 200 and the second circuit board 300 may be flexibly changed according to actual use and design requirements to further expand the applicability of the circuit board assembly 50 provided in the embodiment of the present application. Therefore, the present application does not make any special limitation on this.

[0129] Based on this, the specific structure of the circuit board assembly 50 provided in the embodiment of the present application is described in detail above. The following is a detailed description of the manufacturing method of the circuit board assembly 50. Fig.18 , Fig.18 This is a flow chart of a method for manufacturing a circuit board assembly 50 provided in an embodiment of the present application. The manufacturing method may include the following steps S1-S5.

[0130] S1. Prepare a plurality of sub-circuit boards 110.

[0131] See also Fig.19 , Fig. 20 , Fig.21 , Fig.19 A structural diagram of a sub-circuit board 110 (first sub-circuit board 111) provided in an embodiment of the present application, Fig. 20 A structural diagram of a sub-circuit board 110 (a second sub-circuit board 112) provided in an embodiment of the present application, Fig.21 This is a structural diagram of the sub-circuit board 110 (third sub-circuit board 113) provided in an embodiment of the present application.

[0132] The above-mentioned sub-circuit boards 110 are all conventional PCB boards. Each sub-circuit board 110 may include multiple metal layers 114 and multiple dielectric layers 115. The metal layers 114 and the dielectric layers 115 are alternately stacked in sequence. In addition, the adjacent metal layers 114 may be electrically connected through the vias 116. The vias 116 include mechanically controlled depth drilling holes (such as Fig.19 The rectangular structure of the conductive hole 116) and the laser deep V hole (such as Fig. 20 The via hole 116 of the trapezoidal structure).

[0133] The following description is made by taking an example that three sub-circuit boards 110 are provided, namely a first sub-circuit board 111 , a second sub-circuit board 112 , and a third sub-circuit board 113 .

[0134] S2, pressing and fixing a plurality of sub-circuit boards 110 to form a frame board blank 101.

[0135] Specifically, the plurality of sub-circuit boards 110 are bonded, fixed and pressed together by bonding materials, that is, a bonding layer 140 is provided between two adjacent sub-circuit boards 110, so as to form an integral structure. For example, the bonding material may be PP material (polypropylene) or RCC material (resin coated copper).

[0136] For example, the first sub-circuit board 111, the second sub-circuit board 112 and the third sub-circuit board 113 are taken as examples. Fig. 22 , Fig. 22 for Fig.19 The first sub-circuit board 111 and Fig. 20 A structural diagram of the second sub-circuit board 112 after being pressed and fixed is provided. The first sub-circuit board 111 and the second sub-circuit board 112 are pressed and fixed, that is, the first sub-circuit board 111 and the second sub-circuit board 112 are bonded by an adhesive layer 140. The pressed first sub-circuit board 111 and the second sub-circuit board 112 are punched and electroplated to form a through hole 116, so that the metal layer 114 of the first sub-circuit board 111 and the metal layer 114 of the second sub-circuit board 112 can be electrically connected.

[0137] Next, see Fig.23 and Fig.24 , Fig.23 for Fig. 22 The structure diagram of the first sub-circuit board 111 and the second sub-circuit board 112 after lamination and before lamination of the third sub-circuit board 113 is provided, Fig.24 for Fig.23 A structural diagram of a frame plate blank 101 formed by laminating a first sub-circuit board 111, a second sub-circuit board 112, and a third sub-circuit board 113 is provided. The third sub-circuit board 113 is fixed to a side of the second sub-circuit board 112 away from the first sub-circuit board 111 through an adhesive layer 140, and the laminating first sub-circuit board 111, the second sub-circuit board 112, and the third sub-circuit board 113 are punched and electroplated to form a through hole 116, so that any two of the first sub-circuit board 111, the second sub-circuit board 112, and the third sub-circuit board 113 can be electrically connected to each other, thereby forming the frame plate blank 101.

[0138] The above-mentioned vias 116 for electrically connecting the first sub-circuit board 111, the second sub-circuit board 112 and the third sub-circuit board 113 can be punched from the first surface 111a of the first sub-circuit board 111 and extended to any metal layer 114 of the second sub-circuit board 112, so as to realize the electrical connection between the first sub-circuit board 111 and the second sub-circuit board 112. Similarly, the second surface 113a of the third sub-circuit board 113 is punched and extended to any metal layer 114 of the first sub-circuit board 111, so as to realize the electrical connection between the third sub-circuit board 113 and the second sub-circuit board 112 and the first sub-circuit board 111. Therefore, the present application does not specifically limit the specific process method for opening the vias 116 and the specific structure of the vias 116.

[0139] In some other examples, the first sub-circuit board 111, the second sub-circuit board 112 and the third sub-circuit board 113 may be pressed and fixed first, and then the drilling process may be performed. Fig.25 and Fig.26 , Fig.25 This is a structural diagram of the first sub-circuit board 111, the second sub-circuit board 112 and the third sub-circuit board 113 provided in the embodiment of the present application after being pressed together. Fig.26 for Fig.25 A structural diagram of another frame board blank 101 is provided, in which a via hole 116 is opened on the first sub-circuit board 111, the second sub-circuit board 112, and the third sub-circuit board 113 after lamination to form an HDI (High Density Interconnector) circuit board. Therefore, the present application does not specifically limit the opening time and specific structure of the above-mentioned via hole 116.

[0140] In addition, the first sub-circuit board 111 and the second sub-circuit board 112 include at least three metal layers 114, and a dielectric layer 115 is disposed between two adjacent metal layers 114. The third sub-circuit board 113 includes at least two metal layers 114, and a dielectric layer 115 is disposed between the two metal layers 114.

[0141] Exemplarily, the first sub-circuit board 111 and the second sub-circuit board 112 each include four metal layers 114, and two adjacent metal layers 114 are fixedly connected via a dielectric layer 115. The third sub-circuit board 113 may include two metal layers 114, and the two metal layers 114 are fixedly connected via a dielectric layer 115.

[0142] In this way, since the dielectric layer 115 has a larger expansion coefficient, the first sub-circuit board 111 is configured to have a structure with multiple metal layers 114 and multiple dielectric layers 115, which is conducive to alleviating the extrusion force formed when the dielectric layer 115 of the first sub-circuit board 111 expands toward the second sub-circuit board 112.

[0143] Specifically, when the above-mentioned dielectric layer 115 expands, it will apply an extrusion pressure to the metal layers 114 on both sides. When the first sub-circuit board 111 has multiple dielectric layers 115, part of the extrusion pressure will be offset between two adjacent dielectric layers 115, thereby reducing the extrusion pressure applied by the first sub-circuit board 111 to the second sub-circuit board 112, thereby reducing the risk of damage to the second sub-circuit board 112 due to the extrusion pressure of the first sub-circuit board 111 and the third sub-circuit board 113 on both sides, which is beneficial to improving the reliability of the overall structure.

[0144] Furthermore, by using a multi-layer metal layer 114 structure for the first sub-circuit board 111 and a two-layer metal layer 114 and a dielectric layer 115 structure for the third circuit board, the risk of damage to the second sub-circuit board 112 can be reduced, the reliability of the overall structure can be improved, and the production cost can be reduced.

[0145] S3. Open a receiving space on the frame plate blank 101.

[0146] Specifically, part of the material on the surface of the frame plate 100 can be removed by laser opening or controlled depth milling to form a receiving space, and the receiving space can accommodate the electronic device 40, thereby forming the above-mentioned frame plate 100 structure.

[0147] In some embodiments, the frame plate blank 101 formed by the three sub-circuit boards 110 is taken as an example. When the laser opening process is used to open the accommodation space, in order to facilitate the removal of some materials, a film lamination step is required before the first sub-circuit board 111, the second sub-circuit board 112 and the third sub-circuit board 113 are pressed together.

[0148] See also Fig. 27 , Fig.28 as well as Fig.29 , Fig. 27 This is a structural diagram of the second sub-circuit board 112 (facing the surface of the first sub-circuit board 111) provided in an embodiment of the present application. Fig.28 This is a structural diagram of the second sub-circuit board 112 (the surface facing the third sub-circuit board 113) provided in an embodiment of the present application. Fig.29 This is a structural diagram of another frame plate blank 101 provided in an embodiment of the present application.

[0149] The surface of the second sub-circuit board 112 facing the first sub-circuit board 111 includes a first area 112a and a second area 112b, the adhesive layer 140 is disposed on the first area 112a, and a peeling film layer 150 is disposed on the second area 112b (for example, the peeling film layer 150 may be a peelable protective adhesive), and then the first sub-circuit board 111 and the second sub-circuit board 112 are pressed and fixed. At the same time, the surface of the second sub-circuit board 112 facing the third sub-circuit board 113 also has the first area 112a and the second area 112b, and the adhesive layer 140 is disposed on the first area 112a, and the peeling film layer 150 is disposed on the second area 112b (there is also a certain gap between the two). Then the second sub-circuit board 112 and the third sub-circuit board 113 are pressed and fixed.

[0150] There may be a certain gap between the adhesive layer 140 and the release film layer 150 , and the metal layer 114 (ie, the copper layer) on the second sub-circuit board 112 may be exposed at the gap to facilitate laser cutting in subsequent steps.

[0151] Then, see Fig.30 , Fig.30 for Fig.29 A cross-sectional view of the frame plate blank 101 being laser cut is provided. On the first surface 111a of the first sub-circuit board 111, laser cutting is performed along the edge of the second area 112b, that is, cutting is performed along the extension path of the above-mentioned gap. Since the metal layer 114 (i.e., the copper layer) is exposed at the gap, the cutting depth of the laser along the Z-axis direction can be limited. Then, the laser is made to cut along the second area 112b.

[0152] It should be noted that during the above-mentioned laser cutting process, the laser will first cut along the Z-axis direction and extend to the second sub-circuit board 112, and the metal layer 114 of the second sub-circuit board 112 will block the laser from extending further. In the area on the first sub-circuit board 111 that needs to be laser cut, the metal layer can be etched away by an etching process when making the sub-circuit board 110, thereby avoiding affecting the laser opening. Therefore, during the laser cutting process, there is no metal layer 114 in the cutting path of the first sub-circuit board 111, so that the laser cutting can be completed.

[0153] Next, remove the part of the material on the first sub-circuit board 111 that overlaps with the second area 112b. Due to the material properties of the peeling film 150, it will not adhere to the second sub-circuit board 112, so it can be easily removed (for example, by sticking the tape on the material corresponding to the second area 112b of the first sub-circuit board 111, and applying external force to uncover the corresponding part of the material, i.e., the uncovering step), so that the above-mentioned first accommodation space 120 can be formed on the first surface 111a. Similarly, the above-mentioned second accommodation space 130 can be formed on the second surface 113a by using the same steps.

[0154] It should be noted that, in order to ensure the connection strength of the frame plate blank 101, the peeling film layer 150 and the first sub-circuit board 111 and the third sub-circuit board 113 can be bonded and fixed by ink or other adhesive materials to ensure that the peeling film layer 150 can be separated from the second circuit board 300 when the cover is opened.

[0155] The frame plate 100 is now formed. Fig.31 and Fig.32 , Fig.31 This is a schematic diagram of the structure of spraying solder paste on the frame plate 100 provided in an embodiment of the present application. Fig.32 for Fig.31 A process flow chart of manufacturing a circuit board assembly 50 formed by a frame board 100, a first circuit board 200 and a second circuit board 300 is provided. Fig.31 The cross-section lines indicate the metal layer 114 and the vias 116 inside the frame board 100 , so as to achieve electrical conduction inside the frame board 100 .

[0156] In addition, if the first accommodating space 120 or the second accommodating space 130 is different from the above structure, for example, the depth is different, etc., it is necessary to adjust the setting position of the peeling film layer 150. Fig.16 As an example, since the second accommodating space 130a penetrates the third sub-circuit board 113 and the second sub-circuit board 112, please refer to Fig.33 and Fig.34 , Fig.33 This is a structural diagram of the first sub-circuit board 111 (the surface facing the second sub-circuit board 112) provided in an embodiment of the present application. Fig.34 This is a structural diagram of another second sub-circuit board 112 (the surface facing the first sub-circuit board 111) provided in an embodiment of the present application. The peeling film layer 150 is disposed on the surface of the first sub-circuit board 111 facing the second sub-circuit board 112, and the peeling film layer 150 is bonded and fixed to the second sub-circuit board 112.

[0157] In this way, please refer to Fig.35 and Fig.36, Fig.35 for Fig.33 A first sub-circuit board 111 is provided, Fig.34 A cross-sectional view of the second sub-circuit board 112 and the third sub-circuit board 113 after being pressed and fixed is provided, Fig.36 The schematic diagram of the local structure of the frame plate 100 provided in the embodiment of the present application is a schematic diagram of the local structure of the solder paste spraying. The laser opening can remove the part of the material corresponding to the peeling film layer 150 on the third sub-circuit board 113 and the second sub-circuit board 112 to form the second receiving space 130 with a relatively large depth dimension.

[0158] In other embodiments, when the controlled depth milling process is used to open the accommodation space, compared with the above method, it is not necessary to provide the peeling film layer 150. That is, the frame plate blank 101 is milled by a CNC machine tool to open the first accommodation space 120 on the first surface 111a, and the second accommodation space 130 on the second surface 113a.

[0159] For example, in the frame plate blank 101, the first sub-circuit board 111 includes four metal layers 114, the second sub-circuit board 112 includes four metal layers 114, and the third sub-circuit board 113 includes two metal layers 114. In addition, the ten metal layers 114 are numbered, and are metal layers 114L1-L10 in the direction from the first sub-circuit board 111 to the third sub-circuit board 113. Fig.37 , Fig.37 This is a structural diagram of the metal layer 114 in the frame plate blank 101 provided in an embodiment of the present application.

[0160] According to the space depth to be opened, the target metal layer 114 is determined, such as Fig.35 The second accommodation space 130a shown needs to penetrate the third sub-circuit board 113 and the second sub-circuit board 112. The third sub-circuit board 113 and the second sub-circuit board 112 have a total of 6 metal layers. Therefore, a current is applied to the fourth metal layer 114 (numbered L4). Then, drilling is started from the second surface 113a along the stacking direction of the metal layer 114. When the drill bit contacts the metal layer 114L4, an electrical signal is generated. At this time, drilling along the stacking direction of the metal layer 114 is stopped, and milling is performed in a direction parallel to the metal layer 114, so that the second accommodation space 130 penetrating the third sub-circuit board 113 and the second sub-circuit board 112 can be formed. Since this processing technology is a conventional technical means, it is not described in detail here.

[0161] It should be noted that in the process of supporting and manufacturing the frame plate 100, other process steps are also included. Fig.38 , Fig.38This is a process flow chart of the frame board 100 provided in the embodiment of the present application. For example, cutting, inner layer production of the sub-circuit board 110, AOI optical inspection of the inner layer of the sub-circuit board 110, lamination, drilling, electroplating, copper reduction, outer layer production, press baking, solder mask, surface treatment, testing, packaging, etc. Since these are all process steps of the PCB board, they will not be described in detail here.

[0162] S4. Arrange the electronic device 40 on the frame plate 100 .

[0163] Specifically, the electronic device 40 can be arranged on the frame board 100 by using SMT (Surface Mounted Technology) technology. The SMT process includes solder paste printing, component mounting, reflow soldering, AOI (Automated Optical Inspection) optical inspection, board separation and other process steps. Since SMT technology is a conventional process technology, it will not be described in detail here.

[0164] S5. Welding a circuit board onto the frame plate 100 .

[0165] First, the first circuit board 200 and the second circuit board 300 are prepared. The first circuit board 200 and the second circuit board 300 are conventional PCB boards. The electronic devices 40 are respectively arranged on both side surfaces of the first circuit board 200 and the second circuit board 300 by the SMT patch technology.

[0166] Next, the first circuit board 200 is welded on the first surface 111a of the frame board 100. The second circuit board 300 is welded on the second surface 113a of the frame board 100. Thus, the circuit board assembly 50 provided in the embodiment of the present application is formed. Fig.39 , Fig.39 This is a structural diagram of the circuit board assembly 50 and internal metal circuits provided in an embodiment of the present application.

[0167] In addition, the above-mentioned manufacturing method can also be used to manufacture the first circuit board 200 and the second circuit board 300 when the structure is composed of multiple circuit board bodies and the third receiving space 230 is opened. Since the specific processing steps are the same as the above steps, they are not described repeatedly here.

[0168] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0169] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A circuit board assembly, characterized in that: include: a first circuit board; A frame plate comprises a plurality of sub-circuit boards stacked in sequence, two adjacent sub-circuit boards are fixedly connected, and any two of the sub-circuit boards are electrically connected; the surface of the frame plate facing the first circuit board is a first surface, and a first accommodating space is provided on the first surface; the first circuit board is fixed on the first surface and is electrically connected to the frame plate.

2. The circuit board assembly according to claim 1, characterized in that: The first accommodating space extends along the stacking direction of the plurality of sub-circuit boards and penetrates at least one layer of the sub-circuit boards.

3. The circuit board assembly according to claim 1 or 2, characterized in that: A plurality of the first accommodating spaces are provided, and the plurality of the first accommodating spaces are distributed at intervals on the first surface.

4. The circuit board assembly according to claim 3, characterized in that: The first circuit board covers a portion of the first accommodating space.

5. The circuit board assembly according to any one of claims 1 to 4, characterized in that: The surface of the frame plate away from the first circuit board is a second surface, a second accommodation space is provided on the second surface, and the second accommodation space is independent of the first accommodation space; The circuit board assembly further includes a second circuit board, which is fixed on the second surface and electrically connected to the frame board.

6. The circuit board assembly according to claim 5, characterized in that: On a plane parallel to the sub-circuit board, a partial area of ​​a vertical projection of the first accommodating space overlaps with a partial area of ​​a vertical projection of the second accommodating space; Furthermore, on a plane parallel to the sub-circuit board, the first accommodating space and the second accommodating space whose vertical projections overlap each other are separated by at least one layer of the sub-circuit board.

7. The circuit board assembly according to claim 5, characterized in that: The second accommodating space extends along the stacking direction of the plurality of sub-circuit boards and penetrates at least one layer of the sub-circuit boards.

8. The circuit board assembly according to claim 5, characterized in that: A plurality of the second accommodation spaces are provided, and the plurality of the second accommodation spaces are arranged at intervals on the second surface.

9. The circuit board assembly according to claim 8, characterized in that: The second circuit board covers a portion of the second accommodation space.

10. The circuit board assembly according to any one of claims 5 to 9, characterized in that: The plurality of sub-circuit boards include a first sub-circuit board, a second sub-circuit board and a third sub-circuit board, the second sub-circuit board is arranged between the first sub-circuit board and the third sub-circuit board, the surface of the first sub-circuit board away from the second sub-circuit board is the first surface, and the surface of the third sub-circuit board away from the second sub-circuit board is the second surface; At least one first accommodation space is disposed on the first surface, and at least one second accommodation space is disposed on the second surface.

11. The circuit board assembly according to claim 10, characterized in that: The first accommodation space passes through the first sub-circuit board, and the second accommodation space passes through the third sub-circuit board.

12. The circuit board assembly according to claim 10, characterized in that: There are a plurality of second accommodating spaces, and a portion of the plurality of second accommodating spaces passes through the third sub-circuit board, another portion of the plurality of second accommodating spaces passes through the second sub-circuit board, and the first accommodating space passes through the first sub-circuit board; Wherein, in a plane parallel to the first surface, a vertical projection of the first accommodation space and a vertical projection of the second accommodation space penetrating the second sub-circuit board are arranged in a staggered manner.

13. The circuit board assembly according to claim 10, characterized in that: The sub-circuit board comprises multiple metal layers and multiple dielectric layers, and the multiple metal layers and the multiple dielectric layers are alternately stacked; Wherein, the first sub-circuit board and the second sub-circuit board each include at least three metal layers, and the third sub-circuit board includes at least two metal layers.

14. The circuit board assembly according to any one of claims 1 to 13, characterized in that: At least one electronic device is disposed between the first surface of the frame plate and the first circuit board.

15. The circuit board assembly according to any one of claims 1 to 14, characterized in that: The first circuit board includes a plurality of circuit board bodies, which are stacked and fixedly connected, and two adjacent circuit board bodies are electrically connected; the surface of the first circuit board facing the frame plate is a third surface, a third accommodating space is provided on the third surface, and the third accommodating space is opposite to the first accommodating space.

16. An electronic device, characterized in that: include: Display module; A housing, fixedly connected to the display module; A circuit board assembly is the circuit board assembly according to any one of claims 1 to 15, wherein the circuit board assembly is arranged in the housing.

17. The electronic device according to claim 16, characterized in that: The shell includes a middle frame and a back cover, the middle frame is fixedly connected to the display module, the back cover is fixedly connected to the middle frame and is arranged on a side of the middle frame away from the display module; the back cover has a protruding area protruding in a direction away from the display module; the first accommodating cavity of the circuit board assembly is arranged corresponding to the protruding area.

18. A method for manufacturing a circuit board assembly, characterized in that: include: Fixing and pressing a plurality of sub-circuit boards to form a frame board blank, wherein the frame board blank has a first surface; A first accommodating space is provided on the first surface to form a frame plate; A first circuit board is soldered on the first surface.

19. The manufacturing method according to claim 18, characterized in that: The frame plate blank further has a second surface, which is disposed opposite to the first surface. After the first receiving space is opened on the first surface, the manufacturing method further includes: A second accommodating space is opened on the second surface, and the second accommodating space is independent of the first accommodating space.

20. The manufacturing method according to claim 19, characterized in that: After the first circuit board is soldered on the first surface, the manufacturing method further includes: A second circuit board is soldered on the second surface.

21. The production method according to any one of claims 18 to 20, characterized in that: The plurality of sub-circuit boards include a first sub-circuit board and a second sub-circuit board, the first sub-circuit board and the second sub-circuit board are stacked, a surface of the first sub-circuit board away from the second sub-circuit board is the first surface, and a surface of the second sub-circuit board close to the first sub-circuit board has a first area and a second area; Before the plurality of sub-circuit boards are fixed and pressed together, the manufacturing method further comprises: Disposing an adhesive layer on the first area and a peeling film layer on the second area; The method of opening the first accommodation space on the first surface comprises: Laser cutting the first sub-circuit board along the edge of the second area on the first surface; The portion of the first sub-circuit board that overlaps with the second area and the peeling film layer are removed to form the first accommodating space.

22. The method according to any one of claims 18 to 20, characterized in that: The method of opening the first accommodation space on the first surface comprises: A controlled depth milling process is performed on the first surface to form the first accommodation space.

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