Patent Description:
Embodiments of this application relate to the field of terminal technologies, and in particular, to a circuit board assembly and an electronic device.

As electronic products develop towards the direction of high-density packaging, at present, a plurality of circuit boards are usually stacked to provide a larger arrangement space for a battery and other functional modules in the electronic devices. In the manner of stacking a plurality of circuit boards, electronic components may be scattered on the circuit boards. In this way, all the electronic components can be arranged without increasing areas of the circuit boards that bear the electronic components.

In the manner of stacking a plurality of circuit boards, two adjacent circuit boards are connected by using a frame plate. The frame plate and the circuit boards are assembled to form a circuit board assembly. Different circuit boards may be electrically connected to each other by using a frame plate to implement data information exchange. The circuit boards may be electrically connected to the frame plate by using solder joints. In addition, the solder joints also play a function of mechanical connection and fastening, to provide connection forces between the circuit boards and the frame plate. However, in a scenario with an uneven force, such as a drop or a collision, a connection joint at which the circuit board and the frame plate are connected by using solder joints is prone to a facture. Consequently, the circuit board and the frame plate are separated, and the circuit board assembly malfunctions or fails.

Document <CIT> discloses a circuit board assembly comprising an annular adapter board and two circuit boards arranged on two sides of the adapter board. The distance between the adapter board and each of the circuit boards is determined by a height structure that is provided on the adapter board.

Embodiments of this application provide a circuit board assembly and an electronic device, which can ensure that a large solder joint is formed between two connected pads. This is conducive to improving connection strength between the pads.

A first aspect of this application provides a circuit board assembly. The circuit board assembly is used in an electronic device. The circuit board assembly includes at least a frame plate, circuit boards, support bodies, and solder joints. The frame plate includes a frame body and first pads. The first pads are provided on the frame body. The circuit boards each are provided on one side of the frame plate. The circuit board includes a board body and second pads. The second pads are provided on the board body. The first pads face the second pads. The support bodies are provided between the frame plate and the circuit boards. The support bodies are configured to support the circuit boards, so that a predetermined spacing exists between the first pads and the second pads. The support bodies each include a first support portion and a second support portion. The first support portion and the second support portion are stacked along a thickness direction of the frame plate. The first support portion is connected to the frame body. The second support portion is connected to the board body. Solder joints are provided between the first pads and the second pads. The solder joints connect the first pads to the second pads.

According to the circuit board assembly in this embodiment of this application, in a process of connecting the circuit boards to the frame plate, solder paste is printed on the first pads on the frame plate in advance, and then the circuit boards each are placed on one side of the frame plate. Each of the circuit boards is supported by the support bodies, so that the predetermined spacing can be maintained between the second pads on the circuit board and the first pads on the frame plate. After the solder paste is melted, the circuit board is limited by the support bodies. Therefore, the circuit board does not move close to the frame plate under the action of its own gravity, so that the predetermined spacing can still be maintained between the first pads and the second pads. The first pads and the second pads do not squeeze the molten solder paste, and therefore the molten solder paste does not easily overflow from a space between the first pads and the second pads. The molten solder paste forms the solder joints after being cured. Because the solder joints are large in size, a connection force between the first pads and the solder joints and a connection force between the second pads and the solder joints are large. This effectively reduces a possibility of separation between the first pads and the solder joints or between the second pads and the solder joints in a scenario with an uneven force, such as a drop or a collision. In addition, the molten solder paste does not easily overflow from the space between the first pads and the second pads. This can also effectively reduce a possibility that a short circuit occurs between two first pads or two second pads due to solder paste flowing between the two first pads or the two second pads. This is conducive to increasing a yield of the circuit board assembly.

In a possible implementation, the frame body is an annular structure. Two or more support bodies are spaced along a circumferential direction of the frame body. Supporting each of the circuit boards by a plurality of support bodies is conducive to ensuring that a uniform spacing is maintained between the second pads provided at different locations on the circuit board and the first pads on the frame plate.

In a possible implementation, two or more support bodies are evenly distributed along the circumferential direction of the frame body. A support force applied by each support body to the circuit board is more balanced and uniform. This reduces a possibility that the circuit board inclines when being subject to an unbalanced support force, and is conducive to ensuring that the spacing between the first pads on the frame plate and the second pads on the circuit board tends to be uniform.

In a possible implementation, both the first support portion and the second support portion are solder resist layers. When the solder paste is heated and melted, the first support portion and the second support portion are not easily melted. This reduces a possibility that the circuit board moves close to the frame plate because the first support portion and the second support portion are melted and lose their support functions.

In a possible implementation, both the first support portion and the second support portion are first solder resist ink layers.

In a possible implementation, the first support portion has a uniform thickness, and the second support portion has a uniform thickness. This facilitates printing of the first solder resist ink layer with the uniform thickness on the frame body or the board body by using a printing process, thereby reducing difficulty in manufacturing the first support portion and the second support portion.

In a possible implementation, the thickness of the first support portion is equal to the thickness of the second support portion. This facilitates printing and forming of the first solder resist ink layer with the same thickness on the frame body or the board body by using a printed board with a same thickness, thereby reducing an operation of replacing the printed board, and reducing production difficulty and production costs.

In a possible implementation, the support body further includes a third support portion and a fourth support portion. The first support portion, the second support portion, the third support portion, and the fourth support portion are stacked. The third support portion is provided on a surface of the first support portion that faces the second support portion, and the fourth support portion is provided on a surface of the second support portion that faces the first support portion. By controlling thicknesses of the third support portion and the fourth support portion, the spacing between the first pads and the second pads can be adjusted to improve application flexibility of the support bodies, and the spacing between the first pads and the second pads can be accurately adjusted and controlled.

In a possible implementation, both the third support portion and the fourth support portion are solder resist layers. When the solder paste is heated and melted, the third support portion and the fourth support portion are not easily melted. This reduces a possibility that the circuit board moves close to the frame plate because the third support portion and the fourth support portion are melted and lose their support functions.

In a possible implementation, both the third support portion and the fourth support portion are second solder resist ink layers.

In a possible implementation, both the third support portion and the fourth support portion are insulating sheets.

In a possible implementation, a sum of thicknesses of the first support portion and the third support portion is equal to a sum of thicknesses of the second support portion and the fourth support portion.

In a possible implementation, the third support portion has a uniform thickness, and the fourth support portion has a uniform thickness. This can facilitate printing of the second solder resist ink layer with the uniform thickness on the frame body or the board body by using a printing process to form the third support portion or the fourth support portion, thereby reducing difficulty in manufacturing the third support portion and the fourth support portion. Alternatively, insulating sheets with a predetermined thickness are pre-processed and pre-manufactured by finish machining.

In a possible implementation, the thickness of the third support portion is equal to the thickness of the fourth support portion. This facilitates printing and forming of the second solder resist ink layer on the frame body or the board body by using a printed board with a same thickness, or insulating sheets with a predetermined thickness can be pre-processed and pre-manufactured by finish machining, thereby reducing a possibility of complex processing operations and high production costs caused by a need of processing insulating sheets with two different thicknesses to form the third support portion and the fourth support portion.

In a possible implementation, the frame plate further includes third pads. The third pads are provided on the frame body. The third pads each are covered by the first support portion. The third pads can play a function of positioning references, to help quickly and accurately provide the first support portions at predetermined locations of the frame body. This ensures that the first support portions are located at the predetermined locations, reduces a possibility that support areas between the first support portions and the second support portions become smaller due to misalignment with the second support portions that is resulted from deviation of the first support portions from the predetermined locations, and is also conducive to reducing production difficulty and improving production efficiency. The circuit board further includes fourth pads. The third pads face the fourth pads. The fourth pads each are covered by the second support portion. The fourth pads can play a function of positioning references, to help quickly and accurately provide the second support portions at predetermined locations of the board body. This ensures that the second support portions are located at the predetermined locations, reduces a possibility that support areas between the first support portions and the second support portions become smaller due to misalignment with the first support portions that is resulted from deviation of the second support portions from the predetermined locations, and is also conducive to reducing production difficulty and improving production efficiency.

In a possible implementation, a surface of the first pad that faces the second pad is flush with a surface of the third pad that faces the fourth pad, and a surface of the second pad that faces the first pad is flush with a surface of the fourth pad that faces the third pad. The spacing between the first pads and the second pads can be accurately controlled by controlling the thicknesses of the first support portions and the second support portions.

A second aspect of the embodiments of this application provides an electronic device, including the circuit board assembly described above.

The circuit board assembly includes at least a frame plate, circuit boards, support bodies, and solder joints. The frame plate includes a frame body and first pads. The first pads are provided on the frame body. The circuit boards each are provided on one side of the frame plate. The circuit board includes a board body and second pads. The second pads are provided on the board body. The first pads face the second pads. The support bodies are provided between the frame plate and the circuit boards. The support bodies are configured to support the circuit boards, so that a predetermined spacing exists between the first pads and the second pads. The support bodies each include a first support portion and a second support portion. The first support portion and the second support portion are stacked along a thickness direction of the frame plate. The first support portion is connected to the frame body. The second support portion is connected to the board body. Solder joints are provided between the first pads and the second pads. The solder joints connect the first pads to the second pads.

<FIG> schematically shows a structure of an electronic device <NUM> according to an embodiment. As shown in <FIG>, an embodiment of this application provides the electronic device <NUM>. The electronic device <NUM> may be a mobile terminal, a fixed terminal, or a foldable device, such as a monitor, a handheld wireless communication device, a desktop computer, a laptop (laptop) computer, a tablet (Tablet) computer, an ultra-mobile personal computer (UMPC), a handheld computer, a walkie-talkie, a netbook, a POS machine, or a personal digital assistant (personal digital assistant, PDA).

For ease of description, an example in which the electronic device <NUM> is a handheld wireless communication device is used for description in all of the following embodiments. The handheld wireless communication device may be a mobile phone.

<FIG> schematically shows a breakdown structure of the electronic device <NUM> according to an embodiment. As shown in <FIG>, the electronic device <NUM> includes a display assembly <NUM>, a middle frame <NUM>, a circuit board assembly <NUM>, and a rear cover <NUM>. The display assembly <NUM> has a display region for displaying image information. The display region faces away from the middle frame <NUM>. In a power-on state, the display region can display corresponding image information. The middle frame <NUM> is provided between the display assembly <NUM> and the rear cover <NUM> along a thickness direction of the electronic device <NUM>. It should be noted that, the thickness direction of the electronic device <NUM> refers to an arrangement direction of the display assembly <NUM> and the rear cover <NUM>. The circuit board assembly <NUM> is provided in a space formed between the middle frame <NUM> and the rear cover <NUM>. The circuit board assembly <NUM> may be provided on a surface of the middle frame <NUM> that faces the rear cover <NUM>.

The circuit board assembly <NUM> may include circuit boards <NUM> and a plurality of electronic components <NUM> electrically connected to the circuit boards <NUM>.

The circuit board <NUM> in this application may be a printed circuit board (Printed Circuit Board, PCB), a flexible printed circuit (Flexible Printed Circuit, FPC), or an integrated circuit (or referred to as a chip). The circuit board <NUM> may be a single-sided board or double-sided board. "Single-sided board" means that the electronic components <NUM> are provided on one side of the circuit board <NUM>. "Double-sided board" means that the electronic components <NUM> are provided on both sides of the circuit board <NUM>. The circuit board <NUM> may be a radio frequency (radio frequency, RF) board or an application processor (application processor, AP) board. The radio frequency board may be configured to bear a radio frequency integrated circuit (radio frequency integrated circuit, RFIC), a radio frequency power amplifier (radio frequency power amplifier, RFPA), a wireless fidelity (wireless fidelity, Wi-Fi) chip, and the like, but is not limited thereto. For example, the application processor board may be configured to bear a system on chip (system on chip, SOC) element, a double data rate (double data rate, DDR) memory, a primary power management unit (power management unit, PMU), a secondary power management unit, and the like, but is not limited thereto.

For example, when a thickness of the electronic device <NUM> is small but the display assembly <NUM> is large, the circuit board <NUM> may have a large lateral size, so that one circuit board <NUM> may be selected for use and a fixed quantity of electronic components <NUM> may be provided on the circuit board <NUM>. The lateral size refers to a size measured along a direction perpendicular to the thickness direction of the electronic device <NUM>. If the quantity and volumes of the electronic components <NUM> are large, a structure of the circuit board assembly <NUM> needs to be optimized when not all of the electronic components <NUM> can be accommodated on one circuit board <NUM>. For example, a plurality of the circuit boards <NUM> are stacked along the thickness direction of the electronic device <NUM>, and the electronic components <NUM> are provided on different circuit boards <NUM>. In this way, an internal space of the electronic device <NUM> can be fully utilized along the thickness direction of the electronic device <NUM> to accommodate more and larger electronic components <NUM>.

<FIG> schematically shows a breakdown structure of the circuit board assembly <NUM> in a related technology. <FIG> schematically shows a partial cross-sectional structure of the circuit board assembly <NUM> shown in <FIG>. As shown in <FIG>, in the related technology, the circuit board assembly <NUM> includes the circuit boards <NUM> and a frame plate <NUM>. Two circuit boards <NUM> and the frame plate <NUM> are stacked along a thickness direction X of the frame plate <NUM>. The frame plate <NUM> is provided between the two circuit boards <NUM>. The two circuit boards <NUM> are separately connected to the frame plate <NUM>, so that a predetermined distance is maintained between the two circuit boards <NUM> and locations of the two circuit boards <NUM> do not interfere with each other. The two circuit boards <NUM> may also be electrically connected to each other by using the frame plate <NUM>, so that data information can be mutually transmitted between the two circuit boards <NUM>. The frame plate <NUM> has an annular structure as a whole, so that the frame plate <NUM> includes a middle accommodating hole 42a. For example, the frame plate <NUM> may have a polygonal structure, such as a rectangular structure. After the two circuit boards <NUM> are connected to the frame plate <NUM>, the electronic components <NUM> on the two circuit boards <NUM> may be located in the middle accommodating hole 42a, to avoid locations of the frame plate <NUM> and the electronic components <NUM> from interfering with each other. A thickness of the frame plate <NUM> needs to ensure that the electronic components <NUM> that are located in the middle accommodating hole 42a and that are located on the two circuit boards <NUM> do not reach contact with each other.

The frame plate <NUM> includes a frame body <NUM> and first pads <NUM>. The frame body <NUM> is an annular structure. The frame body <NUM> has the intermediate accommodating hole 42a. The first pads <NUM> are provided on the frame body <NUM>. For example, a material of the first pads <NUM> may be copper or a copper alloy. The circuit board <NUM> includes a board body <NUM> and second pads <NUM>. The second pads <NUM> are provided on the board body <NUM>. The first pads <NUM> face the second pads <NUM>, so that locations of the first pads <NUM> mutually correspond to locations of the second pads <NUM>. Solder joints are located between the first pads <NUM> and the second pads <NUM>. The solder joints connect the first pads <NUM> to the second pads <NUM>. A shape of the solder joint may be but is not limited to a spherical shape, an ellipsoidal shape, a cylindrical shape, or a truncated-cone shape. The first pads <NUM> include functional pads and non-functional pads. The functional pads can play an electrical connection function and a mechanical fastening function. After the two circuit boards <NUM> are connected to the frame plate <NUM>, the two circuit boards <NUM> can transmit electrical signals to each other by using the functional pads. The non-functional pads can play a mechanical fastening function, but the two circuit boards <NUM> cannot transmit electrical signals to each other by using the non-functional pads.

When the circuit boards <NUM> need to be connected to the frame plate <NUM>, solder paste is printed on the first pads <NUM> in advance. The solder paste may include tin and a solder flux. Then, the circuit boards <NUM> each are provided on one side of the frame plate <NUM> and made to reach contact with the solder paste. The solder paste is heated and melted, so that the first pads <NUM> and the second pads <NUM> are all connected to the molten solder paste. After the molten solder paste is cured, solder joints <NUM> are formed, so that the circuit boards <NUM> are connected to the frame plate <NUM> by using the solder joints <NUM>.

The molten solder paste heated has fluidity. As the circuit board <NUM> and the frame plate <NUM> each have specific mass, after the solder paste is melted, the circuit board <NUM> moves close to the frame plate <NUM> under the action of its own gravity. Therefore, a spacing between the first pads <NUM> of the frame plate <NUM> and the second pads <NUM> of the circuit board <NUM> is reduced, and the first pads <NUM> and the second pads <NUM> squeeze the molten solder paste. As a result, the solder paste is squeezed, and a remaining amount of the solder paste is small. When remaining solder paste between the first pads <NUM> and the second pads <NUM> is little, the solder joints <NUM> formed after the solder paste is cured are small in size. Consequently, a connection force between the first pads <NUM> and the solder joints <NUM> and a connection force between the second pads <NUM> and the solder joints <NUM> are small. It should be noted that, the connection force refers to a force that needs to be overcome for the pads to be separated from the solder joints. The force required for separating the pads from the solder joints refers to a tensile stress, along a direction away from the solder joints, that is applied to the pads along the thickness direction X and that is required for separating the pads from the solder joints. Therefore, in a scenario with an uneven force, such as a drop or a collision, a connection joint at which the circuit board <NUM> and the frame plate <NUM> are connected by using the solder joints <NUM> is prone to a facture. Consequently, the circuit board <NUM> and the frame plate <NUM> are separated, and the circuit board assembly <NUM> malfunctions or fails. In addition, the solder paste that overflows from between the first pads <NUM> and the second pads <NUM> flows between two adjacent first pads <NUM> or between two adjacent second pads <NUM>. This leads to a short circuit between the two first pads <NUM> or between the two second pads <NUM>, thereby causing the circuit board assembly <NUM> to be scrapped.

The following further describes an implementation of the circuit board assembly <NUM> provided in this embodiment of this application.

<FIG> schematically shows a partial cross-sectional structure of the circuit board assembly <NUM> according to an embodiment of this application. As shown in <FIG> and <FIG>, the circuit board assembly <NUM> in this embodiment of this application is used in the electronic device <NUM>. The circuit board assembly <NUM> includes circuit boards <NUM>, a frame plate <NUM>, support bodies <NUM>, and solder joints <NUM>. The frame plate <NUM> includes a frame body <NUM> and first pads <NUM>.

For example, the frame body <NUM> is an annular structure, and therefore forms an intermediate accommodating hole 42a.

For example, a material of the frame body <NUM> is an insulating material such as phenolic resin, epoxy resin, or polytetrafluoroethylene. The first pads <NUM> are provided on the frame body <NUM>. The circuit boards <NUM> each are provided on one side of the frame plate <NUM>. The circuit board <NUM> includes a board body <NUM> and second pads <NUM>.

For example, a material of the board body <NUM> is an insulating material such as phenolic resin, epoxy resin, or polytetrafluoroethylene. Electronic components may be provided on the board body <NUM>. The second pads <NUM> are provided on the board body <NUM>, and the first pads <NUM> face the second pads <NUM>. A quantity of the first pads <NUM> may be equal to a quantity of the second pads <NUM>.

According to the circuit board assembly <NUM> in this embodiment of this application, the support bodies <NUM> are provided between the circuit boards <NUM> and the frame plate <NUM>, so that a predetermined spacing L exists between the first pads <NUM> and the second pads <NUM>. This reduces a possibility that solder paste overflows from between the first pads <NUM> and the second pads <NUM> because the first pads <NUM> and the second pads <NUM> excessively squeeze the molten solder paste, and is conducive to ensuring that the molten solder paste is located between the first pads <NUM> and the second pads <NUM>. Therefore, the solder joints <NUM> formed after the solder paste is cured are large in size, and a connection force between the first pads <NUM> and the solder joints <NUM> and a connection force between the second pads <NUM> and the solder joints <NUM> are effectively increased. This reduces a possibility that a connection joint at which the circuit board <NUM> and the frame plate <NUM> are connected by using the solder joints <NUM> is prone to a fracture in a scenario with an uneven force, such as a drop or a collision.

It should be noted that, that a predetermined spacing L exists between the first pads <NUM> and the second pads <NUM> means that the spacing between the first pads <NUM> and the second pads <NUM> can allow a proper solder paste melting space to be formed between the first pads <NUM> and the second pads <NUM>, so as to ensure that the first pads <NUM> and the second pads <NUM> are both in contact with the solder paste, without squeezing the solder paste out from between the first pads <NUM> and the second pads <NUM>.

<FIG> schematically shows a top-view structure of the frame plate <NUM> according to an embodiment of this application. Referring to <FIG> and <FIG>, the support bodies <NUM> are provided between the frame plate <NUM> and the circuit boards <NUM>. The support bodies <NUM> are configured to support the circuit boards <NUM>, so that the predetermined spacing L exists between the first pads <NUM> and the second pads <NUM>. The support bodies <NUM> each include a first support portion <NUM> and a second support portion <NUM>. The first support portion <NUM> and the second support portion <NUM> are stacked along a thickness direction X of the frame plate <NUM>. The first support portion <NUM> is connected to the frame body <NUM>, and the second support portion <NUM> is connected to the board body <NUM> of the circuit board <NUM>. The first support portion <NUM> and the second support portion <NUM> are separately provided. The stacked first support portion <NUM> and second support portion <NUM> can support the circuit board <NUM>. The solder joints <NUM> are provided between the first pads <NUM> and the second pads <NUM>. The solder joints <NUM> connect the first pads <NUM> to the second pads <NUM>.

According to the circuit board assembly <NUM> in this embodiment of this application, in a process of connecting the circuit boards <NUM> to the frame plate <NUM>, the solder paste is printed on the first pads <NUM> on the frame plate <NUM> in advance, and then the circuit boards <NUM> each are placed on one side of the frame plate <NUM>. Each of the circuit boards <NUM> is supported by the support bodies <NUM>, so that the predetermined spacing L can be maintained between the second pads <NUM> on the circuit board <NUM> and the first pads <NUM> on the frame plate <NUM>. After the solder paste is melted, the circuit board <NUM> is limited by the support bodies <NUM>. Therefore, the circuit board <NUM> does not move close to the frame plate <NUM> under the action of its own gravity, so that the predetermined spacing L can still be maintained between the first pads <NUM> and the second pads <NUM>. The first pads <NUM> and the second pads <NUM> do not squeeze the molten solder paste, and therefore the molten solder paste does not easily overflow from the space between the first pads <NUM> and the second pads <NUM>. The molten solder paste forms the solder joints <NUM> after being cured. Because the solder joints <NUM> are large in size, the connection force between the first pads <NUM> and the solder joints <NUM> and the connection force between the second pads <NUM> and the solder joints <NUM> are large. This effectively reduces a possibility of separation between the first pads <NUM> and the solder joints <NUM> or between the second pads <NUM> and the solder joints <NUM> in a scenario with an uneven force, for example, the circuit board assembly <NUM> drops or collides. In addition, the molten solder paste does not easily overflow from the space between the first pads <NUM> and the second pads <NUM>. This can also effectively reduce a possibility that a short circuit occurs between two first pads <NUM> or two second pads <NUM> due to solder paste flowing between the two first pads <NUM> or the two second pads <NUM>. This is conducive to increasing a yield of the circuit board assembly <NUM>.

In some feasible implementations, a surface of the first support portion <NUM> that faces the second support portion <NUM> and a surface of the second support portion <NUM> that faces the first support portion <NUM> come into contact with each other. Before the circuit board <NUM> is connected to the frame plate <NUM>, the first support portion <NUM> may be connected to the frame body <NUM> in advance, and the second support portion <NUM> may be connected to the board body <NUM> of the circuit board <NUM> in advance. After the solder paste is printed on the first pads <NUM>, the circuit board <NUM> is placed on one side of the frame plate <NUM>, and the second support portion <NUM> on the board body <NUM> of the circuit board <NUM> is made corresponding to the first support portion <NUM> on the frame body <NUM>, and the first pads <NUM> are made corresponding to the second pads <NUM>. The first support portion <NUM> abuts against the second support portion <NUM>, so that the first support portion <NUM> and the second support portion <NUM> play a supporting function.

As shown in <FIG>, two or more support bodies <NUM> are spaced along a circumferential direction of the frame body <NUM>. It should be noted that, the circumferential direction of the frame body <NUM> refers to a direction around the middle accommodating hole 42a. The two or more support bodies <NUM> can support the circuit board <NUM> at different locations. A plurality of first pads <NUM> and an equal quantity of corresponding second pads <NUM> may be provided between two adjacent support bodies <NUM>. Supporting each of the circuit boards <NUM> by a plurality of support bodies <NUM> is conducive to ensuring that a uniform spacing is maintained between the second pads <NUM> provided at different locations on the circuit board <NUM> and the first pads <NUM> on the frame plate <NUM>. This is conducive to ensuring consistency of sizes and dimensions of the solder joints <NUM> formed between the frame plate <NUM> and different regions of the circuit board <NUM>.

<FIG> schematically shows a top-view structure of the circuit board assembly <NUM> according to an embodiment of this application. As shown in <FIG>, for example, the frame plate <NUM> is a rectangular structure. The support bodies <NUM> are respectively provided between four bezels of the frame plate <NUM> and the board body <NUM> of the circuit board <NUM>. The frame plate <NUM> has bezels on long edges. Two or more support bodies <NUM> are provided on each of the bezels on the long edges. This helps reduce a possibility that regions of the circuit board <NUM> that correspond to the bezels are depressed toward the frame plate <NUM> under the action of their own gravity and deformed.

<FIG> schematically shows a top-view structure of the circuit board assembly <NUM> according to another embodiment of this application. As shown in <FIG>, the frame plate <NUM> is a square structure. The support bodies <NUM> are respectively provided between four corner regions of the frame plate <NUM> and the board body <NUM> of the circuit board <NUM>. This helps improve stability of locations of the frame plate <NUM>.

In some examples, as shown in <FIG>, two or more support bodies <NUM> are evenly distributed along a circumferential direction of the frame plate <NUM>. A spacing between every two adjacent support bodies <NUM> is equal. For example, the spacing between the two adjacent support bodies <NUM> may range from five to ten millimeters. The spacing between the two adjacent support bodies <NUM> may be a size measured along the bezel. Therefore, a support force applied by each support body <NUM> to the circuit board <NUM> is more balanced and uniform. This reduces a possibility that the circuit board <NUM> inclines when being subject to an unbalanced support force, and is conducive to ensuring that the spacing between the first pads <NUM> on the frame plate <NUM> and the second pads <NUM> on the circuit board <NUM> tends to be uniform.

Both the first support portion <NUM> and the second support portion <NUM> are solder resist layers. Both the first support portion <NUM> and the second support portion <NUM> have good heat resistance. When the solder paste is heated and melted, the first support portion <NUM> and the second support portion <NUM> are not easily melted. This reduces a possibility that the circuit board <NUM> moves close to the frame plate <NUM> because the first support portion <NUM> and the second support portion <NUM> are melted and lose their support functions. The first support portion <NUM> and the second support portion <NUM> each are insulating materials. The first support portion <NUM> or the second support portion <NUM> does not electrically connect two first pads <NUM> or two second pads <NUM> and therefore does not cause a short circuit.

In some examples, both the first support portion <NUM> and the second support portion <NUM> are first solder resist ink layers. For example, a material of the first solder resist ink layers is green ink. The first solder resist ink layer is printed on the frame body <NUM>, and the first solder resist ink layer forms the first support portion <NUM> with large hardness after being cured. The first solder resist ink layer is printed on the board body <NUM> of the circuit board <NUM>, and the first solder resist ink layer forms the second support portion <NUM> with large hardness after being cured. For example, a thickness of the first support portion <NUM> ranges from <NUM> to <NUM> micrometers. A thickness of the second support portion <NUM> ranges from <NUM> to <NUM> micrometers.

The first support portion <NUM> has a uniform thickness, to be specific, thicknesses of different regions of the first support portion <NUM> are the same. The second support portion <NUM> has a uniform thickness, to be specific, thicknesses of different regions of the second support portion <NUM> are the same. Therefore, this facilitates printing of the first solder resist ink layer with the uniform thickness on the frame body <NUM> or the board body <NUM> by using a printing process, thereby reducing difficulty in manufacturing the first support portion <NUM> and the second support portion <NUM>. For example, the thickness of the first support portion <NUM> is equal to the thickness of the second support portion <NUM>. This facilitates printing and forming of the green ink with the same thickness on the frame body <NUM> or the board body <NUM> by using a printed board with a same thickness, thereby reducing an operation of replacing the printed board, and reducing production difficulty and production costs.

Both the first support portion <NUM> and the second support portion <NUM> are disc-shaped structures. Cross sections of the first pads <NUM> and the second pads <NUM> may be circular.

<FIG> schematically shows a partial cross-sectional structure of the circuit board assembly <NUM> according to an embodiment of this application. As shown in <FIG>, the frame plate <NUM> further includes third pads <NUM>. The third pads <NUM> are provided on the frame body <NUM>. For example, a material of the third pads <NUM> may be copper or a copper alloy. The third pads <NUM> are non-functional pads. The third pads <NUM> each are covered by the first support portion <NUM>. An area of the first support portion <NUM> may be greater than an area of the third pad <NUM>, and the entire third pad <NUM> is located below the first support portion <NUM>. Alternatively, an area of the first support portion <NUM> may be equal to an area of the third pad <NUM>, and the first support portion <NUM> is located on one side of the third pad <NUM>. The first pad <NUM> and the third pad <NUM> are spaced apart. The third pads <NUM> can play a function of positioning references, to help quickly and accurately provide the first support portions <NUM> at predetermined locations of the frame body <NUM>. This ensures that the first support portions <NUM> are located at the predetermined locations, reduces a possibility that support areas between the first support portions <NUM> and the second support portions <NUM> become smaller due to misalignment with the second support portions <NUM> that is resulted from deviation of the first support portions <NUM> from the predetermined locations, and is also conducive to reducing production difficulty and improving production efficiency.

The circuit board <NUM> further includes fourth pads <NUM>. The fourth pads <NUM> are provided on the board body <NUM>. For example, a material of the fourth pads <NUM> may be copper or a copper alloy. The fourth pads <NUM> are non-functional pads. The fourth pads <NUM> each are covered by the second support portion <NUM>. An area of the second support portion <NUM> may be greater than an area of the fourth pad <NUM>, and the entire fourth pad <NUM> is located below the second support portion <NUM>. Alternatively, an area of the second support portion <NUM> may be equal to an area of the fourth pad <NUM>, and the second support portion <NUM> is located on one side of the fourth pad <NUM>. The third pads <NUM> and the fourth pads <NUM> are correspondingly provided. The fourth pads <NUM> can play a function of positioning references, to help quickly and accurately provide the second support portions <NUM> at predetermined locations of the board body <NUM>. This ensures that the second support portions <NUM> are located at the predetermined locations, reduces a possibility that support areas between the first support portions <NUM> and the second support portions <NUM> become smaller due to misalignment with the first support portions <NUM> that is resulted from deviation of the second support portions <NUM> from the predetermined locations, and is also conducive to reducing production difficulty and improving production efficiency.

In some implementations, a surface of the first pad <NUM> that faces the second pad <NUM> is flush with a surface of the third pad <NUM> that faces the fourth pad <NUM>. In addition, a surface of the second pad <NUM> that faces the first pad <NUM> is flush with a surface of the fourth pad <NUM> that faces the third pad <NUM>. In this way, a sum of thicknesses of portions, of the first support portion <NUM> and the second support portion <NUM>, that are each located between the third pad <NUM> and the fourth pad <NUM> is equal to a value of the spacing between the first pads <NUM> and the second pads <NUM>. The spacing between the first pads <NUM> and the second pads <NUM> can be accurately controlled by controlling the thicknesses of the first support portions <NUM> and the second support portions <NUM>. For example, the surface of the first pad <NUM> that faces the second pad <NUM>, the surface of the third pad <NUM> that faces the fourth pad <NUM>, the surface of the second pad <NUM> that faces the first pad <NUM>, and the surface of the fourth pad <NUM> that faces the third pad <NUM> are all planar surfaces.

<FIG> schematically shows a partial cross-sectional structure of the circuit board assembly <NUM> according to an embodiment of this application. As shown in <FIG>, the support body <NUM> further includes a third support portion <NUM> and a fourth support portion <NUM>. The first support portion <NUM>, the second support portion <NUM>, the third support portion <NUM>, and the fourth support portion <NUM> are stacked along the thickness direction X of the frame plate <NUM>. The third support portion <NUM> is provided on a surface of the first support portion <NUM> that faces the second support portion <NUM>. The fourth support portion <NUM> is provided on a surface of the second support portion <NUM> that faces the first support portion <NUM>. When a sum of the thicknesses of the first support portion <NUM> and the second support portion <NUM> cannot meet a requirement of the spacing between the first pads <NUM> and the second pads <NUM>, the spacing between the first pads <NUM> and the second pads <NUM> can be further increased by using the third support portion <NUM> and the fourth support portion <NUM>. Therefore, by controlling thicknesses of the third support portion <NUM> and the fourth support portion <NUM>, the spacing between the first pads <NUM> and the second pads <NUM> can be adjusted to improve application flexibility of the support bodies <NUM>, and the spacing between the first pads <NUM> and the second pads <NUM> can be accurately adjusted and controlled.

When the circuit board <NUM> is connected to the frame plate <NUM>, after the solder paste is printed on the first pads <NUM>, the circuit board <NUM> is placed on one side of the frame plate <NUM>, and the fourth support portion <NUM> on the board body <NUM> of the circuit board <NUM> is made corresponding to the third support portion <NUM> on the frame body <NUM>, and the first pads <NUM> are made corresponding to the second pads <NUM>. The third support portion <NUM> abuts against the fourth support portion <NUM>, so that the support body <NUM> plays a supporting function. The spacing between the first pads <NUM> and the second pads <NUM> is equal to a sum of the thicknesses of the first support portion <NUM>, the second support portion <NUM>, the third support portion <NUM>, and the fourth support portion <NUM>.

Both the third support portion <NUM> and the fourth support portion <NUM> are solder resist layers. Both the third support portion <NUM> and the fourth support portion <NUM> have good heat resistance. When the solder paste is heated and melted, the third support portion <NUM> and the fourth support portion <NUM> are not easily melted. This reduces a possibility that the circuit board <NUM> moves close to the frame plate <NUM> because the third support portion <NUM> and the fourth support portion <NUM> are melted and lose their support functions. The third support portion <NUM> and the fourth support portion <NUM> each are insulating materials. The third support portion <NUM> or the fourth support portion <NUM> does not electrically connect two first pads <NUM> or two second pads <NUM> and therefore does not cause a short circuit.

In some examples, both the third support portion <NUM> and the fourth support portion <NUM> are second solder resist ink layers. For example, a material of the second solder resist ink layers is white ink. The second solder resist ink layer is printed on the first support portion <NUM>, and the second solder resist ink layer forms the third support portion <NUM> with large hardness after being cured. The second solder resist ink layer is printed on the second support portion <NUM>, and the second solder resist ink layer forms the fourth support portion <NUM> with large hardness after being cured.

In some examples, both the third support portion <NUM> and the fourth support portion <NUM> are insulating sheets. For example, materials of the third support portion <NUM> and the fourth support portion <NUM> are both plastic, for example, polyethylene terephthalate, polyvinyl chloride, polyethylene, or polypropylene. A third support portion <NUM> and a fourth support portion <NUM> that have a predetermined length and width may be pre-processed and pre-manufactured by finish machining. Then, the third support portion <NUM> is provided on the first support portion <NUM>, and the fourth support portion <NUM> is provided on the second support portion <NUM>. For example, the third support portion <NUM> may be attached to the first support portion <NUM>, and the fourth support portion <NUM> may be attached to the second support portion <NUM>.

In some examples, the third support portion <NUM> is at least partially located between the third pad <NUM> and the fourth pad <NUM>. The fourth support portion <NUM> is at least partially located between the third pad <NUM> and the fourth pad <NUM>. Both the third support portion <NUM> and the fourth support portion <NUM> are disc-shaped structures. Cross sections of the third pads <NUM> and the fourth pads <NUM> may be circular.

A sum of the thicknesses of the first support portion <NUM> and the third support portion <NUM> is equal to a sum of the thicknesses of the second support portion <NUM> and the fourth support portion <NUM>. For example, the first support portion <NUM> and the second support portion <NUM> have a same thickness, and the third support portion <NUM> and the fourth support portion <NUM> have a same thickness. Alternatively, the thickness of the first support portion <NUM> is less than the thickness of the second support portion <NUM>, and the thickness of the third support portion <NUM> is greater than the thickness of the fourth support portion <NUM>. Alternatively, the thickness of the first support portion <NUM> is greater than the thickness of the second support portion <NUM>, and the thickness of the third support portion <NUM> is less than the thickness of the fourth support portion <NUM>.

The third support portion <NUM> has a uniform thickness, and the fourth support portion <NUM> has a uniform thickness. This can facilitate printing of the second solder resist ink layer with the uniform thickness on the frame body <NUM> or the board body <NUM> by using a printing process to form the third support portion <NUM> or the fourth support portion <NUM>, thereby reducing difficulty in manufacturing the third support portion <NUM> and the fourth support portion <NUM>. Alternatively, insulating sheets with a predetermined thickness are pre-processed and pre-manufactured by finish machining.

The thickness of the third support portion <NUM> is equal to the thickness of the fourth support portion <NUM>. This facilitates printing and forming of the second solder resist ink layer on the frame body <NUM> or the board body <NUM> by using a printed board with a same thickness, or insulating sheets with a predetermined thickness can be pre-processed and pre-manufactured by finish machining, thereby reducing a possibility of complex processing operations and high production costs caused by a need of processing insulating sheets with two different thicknesses to form the third support portion <NUM> and the fourth support portion <NUM>.

In the description of the embodiments of this application, it should be noted that, the terms "mounting", "connection", and "connect" should be understood in a broad sense unless otherwise expressly stipulated and limited. For example, "connection" may be a fixed connection, an indirect connection through an intermediate medium, internal communication between two elements, or an interaction relationship between two elements. For a person of ordinary skill in the art, specific meanings of the foregoing terms in the embodiments of this application can be understood based on specific situations.

In the description of the embodiments of this application, it should be understood that directions or positional relationships indicated by direction-related descriptions such as "up", "down", "left", and "right" are based on directions or positional relationships shown by the accompanying drawings, which are used only for describing the embodiments of this application and for description brevity, but do not indicate or imply that an indicated apparatus or element must have a specific direction or must be constructed and operated in a specific direction. Therefore, this cannot be understood as a limitation on the embodiments of this application. In the description of the embodiments of this application, "a plurality of" means two or more, unless otherwise explicitly and specifically specified.

The terms "first", "second", "third", "fourth", and the like (if any) in this specification, the claims, and the accompanying drawings of the embodiments of this application are used to distinguish between similar objects without having to describe a specific order or sequence. It should be understood that, data used in this way may be interchanged under appropriate circumstances, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "including" and "having" and any of their variants are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, and may include other steps or units that are not clearly listed or are inherent to the process, method, product, or device.

The term "a plurality of" in this specification refers to two or more. The term "and/or" in this specification describes only an association relationship for describing associated objects and represents that three relationships can exist. For example, "A and/or B" can represent the following three cases: Only A exists, both A and B exist, and only B exists. In a formula, the character "/" indicates that the associated objects are in a "division" relationship.

It can be understood that, in the embodiments of this application, various numeric numbers are distinguished merely for ease of description and are not used to limit the scope of the embodiments of this application.

Claim 1:
A circuit board assembly (<NUM>), for use in an electronic device (<NUM>), comprising at least the following:
a frame plate (<NUM>), comprising a frame body (<NUM>) and first pads (<NUM>), wherein the first pads are provided on the frame body;
circuit boards (<NUM>), each provided on one side of the frame plate, wherein the circuit board comprises a board body (<NUM>) and second pads (<NUM>), the second pads are provided on the board body, and the first pads face the second pads;
support bodies (<NUM>), provided between the frame plate and the circuit boards, wherein the support bodies are configured to support the circuit boards, so that a predetermined spacing (L) exists between the first pads and the second pads, the support bodies each comprise a first support portion (<NUM>) and a second support portion (<NUM>), the first support portion and the second support portion are stacked along a thickness direction (X) of the frame plate, the first support portion is connected to the frame body, and the second support portion is connected to the board body; and
solder joints (<NUM>), provided between the first pads and the second pads, wherein the solder joints connect the first pads to the second pads, wherein the frame body is an annular structure, and two or more support bodies are spaced along a circumferential direction of the frame body.