WO2024002068A1 - 柔性电路板、电路板组件及电子设备 - Google Patents
柔性电路板、电路板组件及电子设备 Download PDFInfo
- Publication number
- WO2024002068A1 WO2024002068A1 PCT/CN2023/102737 CN2023102737W WO2024002068A1 WO 2024002068 A1 WO2024002068 A1 WO 2024002068A1 CN 2023102737 W CN2023102737 W CN 2023102737W WO 2024002068 A1 WO2024002068 A1 WO 2024002068A1
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- WO
- WIPO (PCT)
- Prior art keywords
- layer
- circuit board
- flexible circuit
- wiring
- layers
- Prior art date
Links
- 239000010410 layer Substances 0.000 claims abstract description 640
- 239000004020 conductor Substances 0.000 claims abstract description 201
- 238000005476 soldering Methods 0.000 claims abstract description 141
- 238000005452 bending Methods 0.000 claims abstract description 120
- 239000002344 surface layer Substances 0.000 claims abstract description 43
- 238000003466 welding Methods 0.000 claims description 205
- 239000011241 protective layer Substances 0.000 claims description 78
- 238000009413 insulation Methods 0.000 claims description 13
- 238000010586 diagram Methods 0.000 description 46
- 229910000679 solder Inorganic materials 0.000 description 29
- 239000002356 single layer Substances 0.000 description 20
- 238000009434 installation Methods 0.000 description 13
- 230000009286 beneficial effect Effects 0.000 description 11
- 230000005540 biological transmission Effects 0.000 description 10
- 238000005516 engineering process Methods 0.000 description 8
- 238000000034 method Methods 0.000 description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 6
- 239000012790 adhesive layer Substances 0.000 description 6
- 239000011889 copper foil Substances 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 230000008054 signal transmission Effects 0.000 description 5
- 239000004642 Polyimide Substances 0.000 description 4
- 239000000853 adhesive Substances 0.000 description 4
- 230000001070 adhesive effect Effects 0.000 description 4
- 230000002411 adverse Effects 0.000 description 4
- 238000005553 drilling Methods 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 229920001721 polyimide Polymers 0.000 description 4
- 238000004080 punching Methods 0.000 description 4
- 238000003491 array Methods 0.000 description 3
- 230000000712 assembly Effects 0.000 description 2
- 238000000429 assembly Methods 0.000 description 2
- 239000011810 insulating material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- RVCKCEDKBVEEHL-UHFFFAOYSA-N 2,3,4,5,6-pentachlorobenzyl alcohol Chemical compound OCC1=C(Cl)C(Cl)=C(Cl)C(Cl)=C1Cl RVCKCEDKBVEEHL-UHFFFAOYSA-N 0.000 description 1
- 230000003190 augmentative effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/11—Printed elements for providing electric connections to or between printed circuits
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/11—Printed elements for providing electric connections to or between printed circuits
- H05K1/118—Printed elements for providing electric connections to or between printed circuits specially for flexible printed circuits, e.g. using folded portions
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
Definitions
- the present application relates to the technical field of circuit connection structures, and in particular to flexible circuit boards, circuit board components and electronic equipment.
- PCB printed circuit boards
- FPC flexible printed circuit
- the traditional flexible circuit board has a large pad spacing, which requires a large welding space to be reserved for both the flexible circuit board and the printed circuit board.
- the circuit board components are larger in size, making it difficult to miniaturize and multiply electronic equipment. Functional.
- This application provides a flexible circuit board.
- the pad spacing of the welding part of the flexible circuit board is small, which can reduce the board area of the welding part and is conducive to miniaturization.
- the present application also provides a circuit board assembly including the above-mentioned flexible circuit board, and an electronic device including the above-mentioned circuit board assembly.
- the present application provides a flexible circuit board having a bending part and a welding part connecting the bending part;
- the flexible circuit board includes a plurality of conductive layers and a plurality of insulating layers, and there is a gap between two adjacent conductive layers.
- An insulating layer is provided;
- a plurality of conductive layers include a first soldering layer, a second soldering layer and a wiring layer.
- the first welding layer and the second welding layer are both located in the welding part.
- the first welding layer is one of the surface layers of the welding part.
- the first welding layer is composed of a plurality of first welding pads spaced apart from each other.
- the first welding layer and the second welding layer are the two surface layers of the welding part
- the first welding layer only arranges the first welding pad and not the wiring
- the second welding layer only arranges the second welding layer.
- the soldering pad does not have traces arranged, so the soldering part does not need to arrange a protective layer (or solder mask) outside the first soldering layer and the second soldering layer, and there is no need to set up a solder mask window structure, so that it can
- the pad spacing of the welding part (that is, the spacing between two adjacent first pads and the spacing between two adjacent second pads) is not limited by the wiring and solder mask window structure.
- the pad spacing is significantly reduced compared to the existing technology, thereby reducing the board area of the welding part, which is conducive to the miniaturization of the flexible circuit board.
- the traces of the flexible circuit board are arranged on the wiring layer, which is the inner structure of the flexible circuit board and is covered by an insulation layer or a protective layer, which is beneficial to improving the line reliability of the flexible circuit board.
- the flexible circuit board of this application has multiple pads separately provided on the soldering layer.
- the setting of the soldering layer may lead to an increase in the number of conductive layers, due to the small thickness of the conductive layer, such as the current
- the thickness of the copper foil layer is usually 0.25 microns. Therefore, the increase in the overall thickness of the flexible circuit board of the present application is small and controllable, and will not cause obvious adverse effects on the miniaturization of circuit board components and electronic equipment using the flexible circuit board. Or obstacles.
- the through-hole conductor may be a conductive layer structure formed on the wall of the through-hole, or a conductive pillar structure filled in the through-hole.
- the wiring layer includes a conductor block and a trace.
- the conductor block is located at the welding part.
- One end of the trace is connected to the conductor block and the other end extends to the bending part.
- the first pad and the second pad pass through Through-hole conductors connect the conductor blocks.
- the first soldering pad and the second soldering pad are connected to the conductor block through a through-hole conductor, and the first soldering pad and the second soldering pad can be electrically connected to other parts or other components of the flexible circuit board via the conductor block and traces.
- the shape of the conductor block may be the same as or similar to the shape of the first pad.
- the area of the conductor block is the same as the area of the first pad.
- the pad spacing of this application can be reduced by about 22% compared to the traditional solution.
- the board area of the welding part of the flexible circuit board of this application can be reduced compared to traditional products. About 40%, the board area of the welding part is greatly reduced, which is conducive to the miniaturization of the flexible circuit board and the miniaturization of circuit board components and electronic equipment using the flexible circuit board.
- the area of the conductor block is smaller than the area of the first pad.
- the positions of the first bonding pad and the second bonding pad are limited by the arrangement of the conductor block.
- the number of wiring layers is multiple layers, and the plurality of conductor blocks connected to the plurality of first pads are located in different wiring layers. Wherein, the conductor blocks to which at least two first pads among the plurality of first pads are connected may be located on different wiring layers.
- the wiring layers arranged with conductor blocks also need to be arranged with traces connected to the conductor blocks, when multiple conductor blocks connected to multiple first pads are concentratedly arranged on a certain layer of the flexible circuit board, When the wiring layer is installed, the wiring layer of this layer will have higher wiring arrangement requirements, which will lead to tight space and difficult wiring arrangement of this wiring layer.
- the conductor blocks corresponding to at least two of the first pads among the plurality of first pads are located in different wiring layers, the wiring connected to the conductor blocks can also be dispersedly arranged in different wiring layers, so that It reduces the wiring difficulty of the wiring layer and improves the wiring flexibility.
- the number of wiring layers is one or more.
- Each wiring layer is provided with multiple punching areas, and multiple through-hole conductors pass through each wiring layer one by one. Multiple punched areas; multiple punched areas of each wiring layer are provided with support blocks, and through-hole conductors pass through the support blocks and connect the support blocks; when the number of wiring layers is one, the support blocks are Conductor block; or, when the number of wiring layers is multiple, the support block is a conductor block or bottom pad.
- each wiring layer of the flexible circuit board is provided with a support block (conductor block or bottom pad)
- the overall support structure of each perforated area of the flexible circuit board is stable and less likely to occur. Collapse, and the thickness of multiple punched areas of the flexible circuit board can be kept consistent, which is beneficial to batch drilling and filling of metal, and improves the production efficiency and yield of the flexible circuit board.
- the plurality of insulating layers includes a first insulating layer and a second insulating layer; the first insulating layer is located between the first welding layer and the adjacent wiring layer, and extends from the welding part to the bend. part, the part of the first insulating layer located in the bent part forms a surface layer of the bent part; the second insulating layer is located between the second welding layer and the adjacent wiring layer, and extends from the welding part to the bent part, The part of the two insulating layers located at the bending part forms another surface layer of the bending part.
- the plurality of conductive layers further include a first wiring layer and a second wiring layer, the first wiring layer and the second wiring layer are both located at the bending part, and the first wiring layer and the first soldering layer are on the same layer.
- the second wiring layer and the second welding layer are arranged on the same layer;
- the flexible circuit board also includes a first protective layer and a second protective layer.
- the first protective layer and the second protective layer are both located at the bending part, and the first protective layer is located at The first wiring layer is on a side facing away from the wiring layer, and the second protective layer is located on a side of the second wiring layer facing away from the wiring layer.
- the first protective layer and the second protective layer are respectively two surface layers of the bending part.
- the bent portion of the flexible circuit board is provided with a first wiring layer and a second wiring layer
- the first wiring layer, the second wiring layer and the wiring layer can all be used to arrange wiring, so the flexible circuit board
- the circuit board can better meet wiring needs such as multiple transmission channels.
- At least one insulation layer of the flexible circuit board forms an air gap at the bending part.
- the structures on both sides of the air gap of the flexible circuit board can move relatively independently to improve the bending performance of the bending portion of the flexible circuit board.
- the application also provides a flexible circuit board having a bending portion and a welding portion connecting the bending portion;
- the flexible circuit board includes a plurality of conductive layers, a plurality of insulating layers and a first protective layer.
- Two adjacent layers There are insulating layers between conductive layers; multiple conductive layers include soldering layers and wiring layers.
- the soldering layer is located at the soldering part.
- the soldering layer is one of the surface layers of the soldering part.
- the soldering layer consists of a plurality of pads spaced apart from each other.
- the wiring layer is located on one side of the soldering layer, and extends from the soldering part to the bending part, the pad is connected to the wiring layer through a through-hole conductor;
- the first protective layer is located on the side of the wiring layer facing away from the soldering layer, and the A protective layer extends from the welding part to the bending part.
- the part of the first protective layer located at the welding part forms another surface layer of the welding part, and the part located at the bending part forms one of the surface layers of the bending part.
- the soldering layer serves as one of the surface layers of the soldering part, and the soldering layer only arranges pads and not traces, the soldering part does not need to arrange a protective layer (or solder mask) outside the soldering layer. layer), there is no need to set up a solder mask window structure, so that the solder mask removal design can be realized.
- the pad spacing of the welding part is not limited by the wiring and the solder mask window structure. The pad spacing is significantly smaller than that of the existing technology. Reduce the board area of the welding part, which is conducive to the miniaturization of flexible circuit boards.
- the flexible circuit board of this application has multiple pads separately provided on the welding layer.
- the arrangement of the welding layer may lead to an increase in the number of conductive layers, since the thickness of the conductive layer is very small, this application The increase in the overall thickness of the flexible circuit board is small and controllable, and will not cause obvious adverse effects or obstacles to the miniaturization of circuit board components and electronic equipment using the flexible circuit board.
- the wiring layer includes a conductor block and a trace.
- the conductor block is located at the welding part.
- One end of the trace is connected to the conductor block and the other end extends to the bending part.
- the soldering pad is connected to the conductor block through a through-hole conductor.
- the pads may be electrically connected to other parts of the flexible circuit board or other components via conductor blocks and traces.
- the shape of the conductor block may be the same as or similar to the shape of the pad.
- the area of the conductor block is the same as the area of the pad.
- the pad spacing of this application can be reduced by about 22% compared to the traditional solution.
- the board area of the welding part of the flexible circuit board of this application can be reduced compared to traditional products.
- the board area of the welding part is greatly reduced, which is conducive to the miniaturization of the flexible circuit board and the circuit application of the flexible circuit board. Miniaturization of board components and electronic equipment.
- the area of the conductor block is smaller than the area of the bonding pad.
- the bonding pad and the second bonding pad are connected to the conductor block through the through-hole conductor, the positions of the bonding pad and the second bonding pad are limited by the arrangement of the conductor block.
- the area of the conductor block By making the area of the conductor block smaller than the area of the bonding pad , so that when the area of the conductor block meets the internal connection requirements (that is, connected to the through-hole conductor), it can be set to a smaller value, so that when the wiring layer meets the wiring arrangement requirements, the two adjacent The distance between the conductor blocks can be smaller, so that the center distance between two adjacent pads can be smaller, which can further reduce the distance between the pads of the welding part, which is beneficial to the miniaturization of the flexible circuit board.
- the number of wiring layers is multiple, and multiple conductor blocks connected to multiple pads are located in different wiring layers.
- the conductor blocks to which at least two of the plurality of pads are connected may be located on different wiring layers. Since the wiring layers with conductor blocks are arranged, it is also necessary to arrange the traces connected to the conductor blocks. When multiple conductor blocks connected to multiple pads are concentrated on a certain wiring layer of the flexible circuit board This will lead to higher wiring arrangement requirements for this wiring layer, which will lead to tight space and difficult wiring arrangement for this wiring layer.
- the wiring connected to the conductor blocks can also be dispersedly arranged in different wiring layers, thereby reducing the wiring cost. Layer wiring difficulty improves wiring flexibility.
- the number of wiring layers is one or more.
- Each wiring layer is provided with multiple punching areas, and multiple through-hole conductors pass through each wiring layer one by one. Multiple punched areas; multiple punched areas of each wiring layer are provided with support blocks, and through-hole conductors pass through the support blocks and connect the support blocks; when the number of wiring layers is one, the support blocks are Conductor block; or, when the number of wiring layers is multiple, the support block is a conductor block or bottom pad.
- each wiring layer of the flexible circuit board is provided with a support block (conductor block or bottom pad)
- the overall support structure of each perforated area of the flexible circuit board is stable and less likely to occur. Collapse, and the thickness of multiple punched areas of the flexible circuit board can be kept consistent, which is beneficial to batch drilling and filling of metal, and improves the production efficiency and yield of the flexible circuit board.
- the plurality of insulating layers includes a first insulating layer.
- the first insulating layer is located between the welding layer and the adjacent wiring layer and extends from the welding part to the bending part.
- the first insulating layer is located between the welding layer and the adjacent wiring layer.
- the portion of the bent portion forms another surface layer of the bent portion.
- the plurality of conductive layers also include a wiring layer, the wiring layer is located at the bending part, and the wiring layer and the welding layer are arranged on the same layer;
- the flexible circuit board also includes a second protective layer, and the second protective layer is located on the wiring layer.
- the second protective layer is located at the bending part and is another surface layer of the bending part.
- At least one insulation layer of the flexible circuit board forms an air gap at the bending part.
- the structures on both sides of the air gap of the flexible circuit board can move relatively independently to improve the bending performance of the bending portion of the flexible circuit board.
- the present application also provides a circuit board assembly, including a circuit board and a flexible circuit board described in any one of the above, and the welding portion of the flexible circuit board welds the circuit board.
- the pads of the welding part of the flexible circuit board have a protruding surface structure, it can avoid solder paste collapse and short circuit during the welding process, ensuring that the solder joints have a certain height, thereby improving the welding quality and reliability.
- the circuit board assembly includes a first circuit board, a second circuit board, a flexible circuit board, a first component and a second component.
- the flexible circuit board includes two welding parts and a bending part connecting the two welding parts.
- the two welding parts of the flexible circuit board weld the first circuit board and the second circuit board respectively.
- the structure of the welding part and the bending part of the flexible circuit board can adopt any of the aforementioned structures.
- the first circuit board may be a printed circuit board or a flexible circuit board
- the second circuit board may be a printed circuit board or a flexible circuit board.
- the number of the first component may be one or more, and the first component is fixed and electrically connected to the first circuit board.
- the number of the second component may be one or more, and the second component is fixed and electrically connected to the second circuit board.
- the flexible circuit board is used to realize electrical connection between the first component and the second component.
- first circuit board and the second circuit board can be stacked, and the bending part of the flexible circuit board is bent, so that the circuit board assembly forms a sandwich stack structure.
- the overall space occupied by the circuit board assembly is small and the required installation space is small. Smaller, which helps to reduce the difficulty of installation and improve the scope of application.
- the first circuit board and the second circuit board may also form other relative positional relationships, such as a staggered arrangement, etc.
- the circuit board assembly includes a first circuit board, a second circuit board, a flexible circuit board, a first electrical connector, a second electrical connector, a first component and a second component.
- the flexible circuit board includes a welding part, a connecting part, and a bending part connecting the welding part and the connecting part.
- the structure of the welding part and the bending part of the flexible circuit board can adopt any of the aforementioned structures.
- the first circuit board may be a printed circuit board or a flexible circuit board.
- the number of the first component may be one or more, and the first component is fixed and electrically connected to the first circuit board.
- the welding part of the flexible circuit board welds the first circuit board.
- the number of the second component may be one or more, and the second component is fixed and electrically connected to the second circuit board.
- the first electrical connector and the second electrical connector may be male and female respectively, and the male and female are paired with each other.
- the first electrical connector and the second electrical connector may be board-to-board electrical connectors or the like.
- the first electrical connector is fixed and electrically connected to the connecting portion of the flexible circuit board, and the second electrical connector is fixed and electrically connected to the second circuit board.
- the first electrical connector is fixed and electrically connected to the second electrical connector, and the flexible circuit board is used to realize electrical connection between the first component and the second component.
- first circuit board and the second circuit board can be stacked, and the bending portion of the flexible circuit board is bent, so that the circuit board assembly forms With the sandwich stack structure, the overall space occupied by the circuit board assembly is smaller, and the required installation space is smaller, which is beneficial to reducing the difficulty of installation and improving the scope of application.
- the first circuit board and the second circuit board may also form other relative positional relationships, such as a staggered arrangement, etc.
- the circuit board assembly includes a circuit board, a flexible circuit board, a first component and a second component.
- the flexible circuit board includes a welding part, a mounting part, and a bending part connecting the welding part and the mounting part.
- the structure of the welding part and the bending part of the flexible circuit board can adopt any of the aforementioned structures.
- the circuit board may be a printed circuit board or a flexible circuit board.
- the number of the first component may be one or more, and the first component is fixed and electrically connected to the circuit board.
- the welding part of the flexible circuit board welds the circuit board.
- the number of the second component may be one or more, and the second component is fixed and electrically connected to the mounting part of the flexible circuit board.
- the flexible circuit board is used to realize electrical connection between the first component and the second component.
- the present application also provides an electronic device, including a housing and the above-mentioned circuit board assembly.
- the circuit board assembly is installed inside the housing.
- Figure 1 is a schematic structural diagram of a traditional flexible circuit board
- Figure 2 is a schematic cross-sectional structural diagram of the flexible circuit board shown in Figure 1 taken along A-A;
- Figure 3 is a partial structural schematic diagram of the flexible circuit board shown in Figure 1;
- Figure 4 is a schematic structural diagram of the flexible circuit board provided by the embodiment of the present application in some embodiments.
- Figure 5 is a schematic cross-sectional structural diagram of the flexible circuit board shown in Figure 4 taken along B-B;
- Figure 6 is a partial structural schematic diagram of the flexible circuit board shown in Figure 4.
- Figure 7 is a partial structural diagram of the wiring layer shown in Figure 5;
- Figure 8 is a schematic diagram of the internal structure of the flexible circuit board provided by the embodiment of the present application in other embodiments;
- Figure 9 is a schematic diagram of the internal structure of the flexible circuit board provided by the embodiment of the present application in other embodiments.
- Figure 10 is a partial structural schematic diagram of the flexible circuit board shown in Figure 9;
- Figure 11 is a schematic diagram of the internal structure of the flexible circuit board provided by the embodiment of the present application in other embodiments;
- Figure 12 is a schematic diagram of the internal structure of the flexible circuit board provided by the embodiment of the present application in other embodiments;
- Figure 13 is a schematic diagram of the internal structure of the flexible circuit board provided by the embodiment of the present application in other embodiments;
- Figure 14 is a schematic diagram of the internal structure of the flexible circuit board provided by the embodiment of the present application in other embodiments;
- Figure 15 is a schematic diagram of the internal structure of the flexible circuit board provided by the embodiment of the present application in other embodiments;
- Figure 16 is a schematic diagram of the internal structure of the flexible circuit board provided by the embodiment of the present application in other embodiments;
- Figure 17 is a schematic structural diagram of the circuit board assembly provided by the embodiment of the present application in some embodiments.
- Figure 18 is a schematic structural diagram of the circuit board assembly shown in Figure 17 from another angle;
- Figure 19 is a partial structural schematic diagram of the circuit board assembly shown in Figure 17;
- Figure 20 is a schematic structural diagram of the circuit board assembly provided by the embodiment of the present application in other embodiments.
- Figure 21 is a partial structural schematic diagram of the circuit board assembly shown in Figure 20;
- Figure 22 is a schematic structural diagram of the circuit board assembly provided by the embodiment of the present application in some embodiments.
- Figure 23 is a schematic structural diagram of the circuit board assembly provided by the embodiment of the present application in other embodiments.
- Figure 24 is a schematic structural diagram of the circuit board assembly provided by the embodiment of the present application in other embodiments.
- connection can It can be detachably connected or non-detachably connected; it can be directly connected or indirectly connected through an intermediate medium.
- first, second and the like are used for descriptive purposes only and cannot be understood as implying or implying relative importance or implicitly specifying the quantity of the technical features indicated. Therefore, features defined as “first” and “second” may explicitly or implicitly include one or more of these features.
- Figure 1 is a schematic structural diagram of a traditional flexible circuit board 20 used in an interconnection structure between soft and hard boards.
- Figure 2 is a cross-section of the flexible circuit board 20 shown in Figure 1 along A-A.
- 3 is a partial structural schematic diagram of the flexible circuit board 20 shown in FIG. 1 .
- the flexible circuit board 20 includes two welding parts 20a and a bending part 20b connecting the two welding parts 20a.
- the bending part 20b is capable of bending and other deformations.
- the flexible circuit board 20 includes a first protective layer 201, a first conductive layer 202, an insulating layer 203, a second conductive layer 204 and a second protective layer 205 that are stacked in sequence.
- the first protective layer 201 and the second protective layer 205 are also insulating layers, which can also be called solder resist layers.
- the first protective layer 201 and the second protective layer 205 are the two surface layers of the flexible circuit board 20 .
- the first conductive layer 202 includes a plurality of bonding pads 2021 and a plurality of traces 2022.
- the first protective layer 201 is provided with a plurality of openings 2011 for exposing the plurality of bonding pads 2021.
- one or more wires 2022 are usually arranged between two adjacent pads 2021.
- R is 0.15mm
- S is 0.075mm
- S1 and S2 are 0.075mm
- W is 0.1mm
- the flexible circuit board adds a welding layer in the welding part that only arranges pads and does not arrange wiring. It adopts a solder mask removal design so that the pad spacing of the welding layer can be protected from wiring. Due to structural limitations such as solder mask openings, the pad spacing can be significantly reduced, thereby reducing the board area of the welding part, which is conducive to the miniaturization of flexible circuit boards.
- the present application also provides a circuit board assembly including the above-mentioned flexible circuit board, and an electronic device including the above-mentioned circuit board assembly.
- Figure 4 is a schematic structural diagram of the flexible circuit board 1 provided by the embodiment of the present application in some embodiments.
- Figure 5 is a cross-sectional structure of the flexible circuit board 1 shown in Figure 4 along B-B.
- Figure 6 is a partial structural schematic diagram of the flexible circuit board 1 shown in Figure 4.
- the flexible circuit board 1 has a bending portion 1a and a welding portion 1b connecting the bending portion 1a.
- the flexible circuit board 1 can be an integrally formed structural member, and the bending portion 1 a and the welding portion 1 b are two parts of the flexible circuit board 1 .
- the bending portion 1a can be deformed such as bending, so that the flexible circuit board 1 can be deformed.
- the flexible circuit board 1 can weld other components (such as a printed circuit board) through the welding portion 1b, that is, the welding portion 1b is used to connect other components to achieve electrical connection with other components.
- the number of welding parts 1b can be two.
- the two welding parts 1b can be connected to both ends of the bending part 1a respectively.
- the two welding parts 1b can be welded to different components respectively.
- the flexible circuit board 1 can realize different components. electrical connection between them.
- the flexible circuit board 1 includes a plurality of conductive layers 11 and a plurality of insulating layers 12 .
- the plurality of conductive layers 11 and the plurality of insulating layers 12 are stacked.
- the insulating layers 12 are provided between two adjacent conductive layers 11 .
- the conductive layer 11 is used to achieve electrical conduction, and the conductive layer 11 can be made of conductive materials such as copper foil.
- the insulating layer 12 is used to achieve an insulating effect, and the insulating layer 12 can be made of insulating materials such as polyimide (PI).
- PI polyimide
- the insulating layer 12 can electrically isolate adjacent conductive layers 11 .
- an adhesive layer (not shown in the drawings) can be provided between the conductive layer 11 and the insulating layer 12 to achieve mutual fixation, or no adhesive layer can be provided, and they can directly contact and fix each other; conductive layers at different positions Whether an adhesive layer is provided between the layer 11 and the adjacent insulating layer 12 may be the same or different.
- the embodiment of the present application does not strictly limit the fixing method and fixing structure of the plurality of conductive layers 11 and the plurality of insulating layers 12 .
- the plurality of conductive layers 11 include a first soldering layer 111 , a second soldering layer 112 and a wiring layer 113 .
- the first welding layer 111 and the second welding layer 112 are both conductive layers.
- the first welding layer 111 and the second welding layer 112 are used to weld other components to achieve electrical connection between the flexible circuit board 1 and other components.
- the first welding layer 111 and the second welding layer 112 are both located at the welding portion 1b.
- the first soldering layer 111 is one of the surface layers of the soldering portion 1b.
- the first soldering layer 111 is composed of a plurality of first soldering pads 1111 spaced apart from each other. In the embodiment of the present application, the arrangement of two structures spaced apart from each other means that the two structures are separated by a certain distance and a gap is formed between them.
- the plurality of first pads 1111 may be arranged in an array or in other arrangements.
- the second soldering layer 112 is another surface layer of the soldering portion 1 b.
- the second soldering layer 112 is composed of a plurality of second soldering pads 1121 spaced apart from each other.
- the plurality of second pads 1121 may be arranged in an array or in other arrangements.
- the surface layer of the welding part 1b refers to the outermost layer structure of the welding part 1b
- the "outside" of the flexible circuit board 1 refers to the orientation close to the external space.
- the wiring layer 113 is a conductive layer, and at least wiring is arranged in the wiring layer 113 to realize electrical signal transmission through the wiring.
- the electrical signal may include, but is not limited to, one or more of a power signal, a ground signal, and a data signal.
- the wiring layer 113 is located between the first soldering layer 111 and the second soldering layer 112, and extends from the soldering portion 1b to the bending portion 1a.
- the number of wiring layers 113 may be one or more. When the number of wiring layers 113 is multiple, an insulation layer is provided between two adjacent wiring layers 113 .
- the first bonding pad 1111 and the second bonding pad 1121 are connected through the through-hole conductor 13 , and the through-hole conductor 13 is connected to the wiring layer 113 .
- the first pad 1111 and the second pad 1121 can be electrically connected through the through-hole conductor 13
- the wiring layer 113 can also be electrically connected through the through-hole conductor 13 .
- the number of the first bonding pads 1111 and the second bonding pads 1121 may be the same, and the plurality of first bonding pads 1111 and the plurality of second bonding pads 1121 may be arranged in one-to-one correspondence, and the corresponding first bonding pads 1111 and the second bonding pads 1121 may have the same number.
- the two pads 1121 are connected through the through-hole conductor 13 .
- the shapes and sizes of the corresponding first pad 1111 and the second pad 1121 may be the same or similar.
- the through-hole conductor 13 may be a conductive layer structure formed on the wall of the through-hole, or a conductive pillar structure filled in the through-hole, which is not strictly limited in the embodiment of the present application.
- the numbers of the first bonding pads 1111 and the second bonding pads 1121 may also be different, and part of the first bonding pad 1111 and part of the second bonding pad 1121 may be arranged correspondingly, or part of the first bonding pad 1111 and part of the second bonding pad 1121 may be arranged correspondingly. All the second bonding pads 1121 are arranged correspondingly, or all the first bonding pads 1111 and part of the second bonding pads 1121 are arranged correspondingly. The corresponding first pad 1111 and the second pad 1121 can still be connected through the through-hole conductor 13 .
- the plurality of insulating layers 12 include a first insulating layer 121 and a second insulating layer 122 .
- the first insulating layer 121 is located between the first soldering layer 111 and the adjacent wiring layer 113, and extends from the soldering portion 1b to the bending portion 1a.
- the first insulation layer 121 isolates the first soldering layer 111 and the adjacent wiring layer 113 at the soldering portion 1b.
- the portion of the first insulating layer 121 located on the bent portion 1a forms a surface layer of the bent portion 1a and forms a protective layer for protecting the internal structure of the bent portion 1a.
- the second insulating layer 122 is located between the second soldering layer 112 and the adjacent wiring layer 113, and extends from the soldering portion 1b to the bending portion 1a.
- the second insulating layer 122 isolates the second soldering layer 112 and the adjacent wiring layer 113 at the soldering portion 1 b.
- the portion of the second insulating layer 122 located on the bent portion 1a forms another surface layer of the bent portion 1a and forms a protective layer for protecting the internal structure of the bent portion 1a.
- FIG. 7 is a partial structural diagram of the wiring layer 113 shown in FIG. 5 .
- the wiring layer 113 includes a conductor block 1131 and a trace 1132.
- the conductor block 1131 is located at the welding part 1 b.
- One end of the trace 1132 is connected to the conductor block 1131 and the other end extends to the bending part 1 a.
- the first soldering pad 1111 and the second soldering pad 1121 are connected to the conductor block 1131 through the through-hole conductor 13 .
- the first soldering pad 1111 and the second soldering pad 1121 can be electrically connected to other parts of the flexible circuit board 1 via the conductive block 1131 and the trace 1132 . parts or other parts.
- the first soldering layer 111 and the second soldering layer 112 serve as the two surface layers of the soldering part 1b
- the first soldering layer 111 only arranges the first soldering pad 1111 and does not arrange traces.
- Layer 112 only arranges the second soldering pad 1121 and does not arrange traces. Therefore, the soldering part 1b does not need to arrange a protective layer (or called a solder resist layer) outside the first soldering layer 111 and the second soldering layer 112, and also There is no need to set up a solder mask window structure, so that the solder mask removal design can be realized.
- the spacing is not limited by the wiring and the solder mask window structure, and the pad spacing is significantly reduced compared to the existing technology, thereby reducing the board area of the welding portion 1b, which is conducive to the miniaturization of the flexible circuit board 1.
- the wiring of the flexible circuit board 1 is arranged in the wiring layer 113, which is the inner structure of the flexible circuit board 1 and is covered by the insulation layer 12 or the protective layer, which is beneficial to improving the circuit reliability of the flexible circuit board 1.
- the flexible circuit board 1 of the present application has multiple soldering pads separately provided on the soldering layer, although the setting of the soldering layer may lead to an increase in the number of conductive layers (for example, the embodiment shown in Figure 5 is compared with the figure The structure shown in 2 adds a conductive layer), but since the thickness of the conductive layer 11 is very small, for example, the current copper foil layer is usually 0.25 microns thick, so the increase in the overall thickness of the flexible circuit board 1 of the present application is small. It is controllable and will not cause obvious adverse effects or obstacles to the miniaturization of circuit board components and electronic equipment using the flexible circuit board 1 .
- the conductor block 1131 and the trace 1132 are both conductive parts.
- the conductor block 1131 is used to electrically connect the first pad 1111 and the second pad 1121 through the through-hole conductor 13 , and can also be used to electrically connect the internal parts of the flexible circuit board 1 .
- the layer conductive structure (such as the trace 1132) enables the flexible circuit board 1 to achieve electrical connection with other components through the first pad 1111 and the second pad 1121.
- the shape of the conductor block 1131 may be the same as or similar to the shape of the first pad 1111, for example, both are circular.
- the area of the conductor block 1131 is the same as the area of the first pad 1111 .
- the center distance between two adjacent first pads 1111 includes: the radius R of the two first pads 1111, the width W of the trace 1132, and the distance between the two first pads 1111 and the trace.
- the pad spacing of the welding part 1b is reduced.
- the pad spacing of the present application can be reduced by about 22% compared to the traditional solution.
- the flexible circuit board 1 of the present application has a smaller welding portion 1b than the traditional product.
- the board area can be reduced by about 40%, and the board area of the welding portion 1b is greatly reduced, which is conducive to the miniaturization of the flexible circuit board 1 and the circuit board components and electronic equipment using the flexible circuit board 1. change.
- FIG. 8 is a schematic diagram of the internal structure of the flexible circuit board 1 provided by the embodiment of the present application in other embodiments.
- the flexible circuit board 1 shown in this embodiment may include most of the technical features in the previous embodiments. The following mainly describes the differences between the two, and the same parts between the two will not be described again.
- the area of the conductor block 1131 may be smaller than the area of the first pad 1111 .
- the positions of the first bonding pad 1111 and the second bonding pad 1121 are limited by the conductor block.
- 1131 is set to a smaller value by making the area of the conductor block 1131 smaller than the area of the first pad 1111 so that the area of the conductor block 1131 meets the internal connection requirements (that is, connected to the through-hole conductor 13).
- the distance between the two adjacent conductor blocks 1131 can be smaller, so that the center distance between the two adjacent first pads 1111 is smaller, so that Further reducing the pad pitch of the welding portion 1 b is beneficial to miniaturization of the flexible circuit board 1 .
- FIG. 9 is a schematic diagram of the internal structure of the flexible circuit board 1 provided by the embodiment of the present application in other embodiments.
- FIG. 10 is a partial structural diagram of the flexible circuit board 1 shown in FIG. 9 .
- the flexible circuit board 1 shown in this embodiment may include most of the technical features in the previous embodiments. The following mainly describes the differences between the two, and the same parts between the two will not be described again.
- the number of wiring layers 113 of the flexible circuit board 1 may be multiple layers, such as two layers, three layers, four layers, etc. This embodiment takes two layers as an example for description and illustration.
- the plurality of conductor blocks 1131 connected by the plurality of first pads 1111 may be distributed and located in different wiring layers 113 .
- the conductor blocks 1131 correspondingly connected to at least two first pads 1111 among the plurality of first pads 1111 may be located on different wiring layers 113 .
- the plurality of first pads 1111 include a first first pad and a second first pad, the first first pad is connected to the first conductor block, and the first conductor block is located on the first On the wiring layer, the second first pad is connected to the second conductor block, and the second conductor block is located on the second wiring layer.
- first and second are descriptions for the purpose of distinguishing two structures, and do not constitute a limit on order, importance, or other limitations.
- the wiring 1132 connected to the conductor block 1131 also needs to be arranged.
- the plurality of conductor blocks 1131 connected to the plurality of first pads 1111 are arranged in a centralized manner, When it is laid on a certain wiring layer 113 of the flexible circuit board 1, this wiring layer 113 will have higher wiring arrangement requirements, which will in turn lead to tight space and wiring arrangement problems for this wiring layer 113. difficulty.
- the conductor blocks 1131 connected to at least two of the plurality of first bonding pads 1111 are located in different wiring layers 113, the wiring 1132 connected to the conductor blocks 1131 can also be distributed in different wiring layers. wiring layer 113, thereby reducing the wiring difficulty of the wiring layer 113 and improving wiring flexibility.
- the welding portion 1 b of the flexible circuit board 1 is provided with multiple punched areas, and the plurality of through-hole conductors 13 pass through the multiple punched areas in one-to-one correspondence.
- the first soldering layer 111, the second soldering layer 112 and the wiring layer 113 are each provided with a plurality of corresponding punched areas.
- the above-mentioned punched area includes both the space occupied by the through-hole conductor 13 and the space located within a certain range around the through-hole conductor 13 .
- a plurality of first bonding pads 1111 are provided in the plurality of punched areas of the first soldering layer 111 , and the plurality of through-hole conductors 13 pass through the plurality of first bonding pads 1111 and are connected to the first bonding pads 1111 .
- the plurality of perforated areas of the second soldering layer 112 are provided with a plurality of second bonding pads 1121 , and the plurality of through-hole conductors 13 pass through the plurality of second bonding pads 1121 and are connected to the second bonding pads 1121 .
- the number of wiring layers 113 may be one or more. Each wiring layer 113 is provided with multiple punching areas. Each punching area is provided with a support block, and multiple through-hole conductors 13 are passed through one by one. Through the plurality of punched areas, the through-hole conductors 13 pass through the support blocks and connect the support blocks. For example, as shown in FIG. 5 , when the number of wiring layers 113 is one layer, and the plurality of conductor blocks 1131 connected by the plurality of first pads 1111 are all located in this layer of wiring layer 113 , they are located in the wiring layer.
- the support block of each punched area of 113 is a conductor block 1131, and the through-hole conductor 13 passes through the conductor block 1131 and is connected to the conductor block 1131.
- the plurality of wiring layers 113 located on each layer are The support block of the punched area can be a conductor block 1131 or a bottom pad 1133 (target pad). That is, when the wiring layer 113 is multi-layered, if the conductor block 1131 is not arranged in the perforated area of the wiring layer 113, the bottom pad 1133 is arranged.
- the bottom pad 1133 and the conductor block 1131 are essentially conductive structures.
- the difference between the two is that the bottom pad 1133 is not connected to the wiring and is a suspended structure in the transmission circuit of the flexible circuit board 1, while the conductor block 1131 is connected to the wiring 1132 , as part of the transmission circuit.
- the area of the bottom pad 1133 may be greater than, less than, or equal to the area of the conductor block 1131, which is not strictly limited in the embodiment of the present application.
- each wiring layer 113 of the flexible circuit board 1 is provided with a support block (conductor block 1131 or bottom pad 1133), the overall support of each perforated area of the flexible circuit board 1 is The structure is stable and not prone to collapse, and the thickness of multiple punched areas of the flexible circuit board 1 can be kept consistent, which is conducive to batch drilling and filling of metal, and improves the production efficiency and yield of the flexible circuit board 1 .
- the thickness of the bent portion 1a of the flexible circuit board 1 is very small. It is small and can ensure bending performance, so that the flexible circuit board 1 can meet diverse installation environments and has better reliability. In some other embodiments, the number of wiring layers 113 of the flexible circuit board 1 can also be larger to meet wiring requirements such as multiple transmission channels.
- FIG. 11 is a schematic diagram of the internal structure of the flexible circuit board 1 provided by the embodiment of the present application in other embodiments.
- the flexible circuit board 1 shown in this embodiment may include most of the technical features in the previous embodiments. The following mainly describes the differences between the two, and the same parts between the two will not be described again.
- the plurality of conductive layers 11 further include a first wiring layer 114 and a second wiring layer 115, and the first wiring layer 114 and the second wiring layer 115 are both located at the bending portion 1a.
- the first wiring layer 114 and the first soldering layer 111 are arranged on the same layer.
- the first wiring layer 114 is a conductive layer, and at least one or more wires are arranged to realize electrical signal transmission through the wires.
- the second wiring layer 115 and the second soldering layer 112 are the same Layer settings.
- the second wiring layer 115 is a conductive layer, and is provided with at least one or more wires to realize electrical signal transmission through the wires.
- the first wiring layer 114 and/or the second wiring layer 115 may be electrically connected to the wiring layer 113 .
- the flexible circuit board 1 also includes a first protective layer 141 and a second protective layer 142.
- the first protective layer 141 and the second protective layer 142 are both located at the bending portion 1a.
- the first protective layer 141 is located behind the first wiring layer 114.
- the second protective layer 142 is located on the side of the second wiring layer 115 facing away from the wiring layer 113.
- the first protective layer 141 and the second protective layer 142 are respectively two surface layers of the bent portion 1a.
- the first protective layer 141 and the second protective layer 142 are both insulating layers used to protect the internal structure of the flexible circuit board 1.
- the first protective layer 141 and the second protective layer 142 may also be called solder resist layers.
- the bent portion 1a of the flexible circuit board 1 is provided with the first wiring layer 114 and the second wiring layer 115, the first wiring layer 114, the second wiring layer 115 and the wiring layer 113 can be used for The wiring is arranged, so the flexible circuit board 1 can better meet the wiring requirements of multiple transmission channels.
- FIG. 12 is a schematic diagram of the internal structure of the flexible circuit board 1 provided by the embodiment of the present application in other embodiments.
- the flexible circuit board 1 shown in this embodiment may include most of the technical features in the previous embodiments. The following mainly describes the differences between the two, and the same parts between the two will not be described again.
- At least one insulating layer 12 of the flexible circuit board 1 can form an air gap (Airgap) at the bending portion 1a, that is, a flexible circuit
- Airgap air gap
- the bent portion 1a of the board 1 forms one or more air gaps, so that the structures on both sides of the air gap of the flexible circuit board 1 can move relatively independently to improve the bending performance of the bent portion 1a of the flexible circuit board 1.
- the flexible circuit board 1 may have a four-layer board structure.
- the plurality of conductive layers 11 of the flexible circuit board 1 may include a first wiring layer 114, a second wiring layer 115, and two wiring layers 113, located on the two wiring layers.
- the insulating layer 12 between 113 can form an air gap 121 at the bent portion 1a.
- the insulating layer 12 located between the two wiring layers 113 may include a first sub-insulating layer 122 and a second sub-insulating layer 123.
- the first sub-insulating layer 122 is at the welding portion 1b and the second sub-insulating layer 123
- the part on the welding part 1b can be pressed and fixed by the adhesive on it, and the adhesive on the part of the first sub-insulating layer 122 on the bending part 1a and the part of the second sub-insulating layer 123 on the bending part 1a can be removed. Or omitted, an air gap 121 is formed between the portion of the first sub-insulating layer 122 at the bent portion 1a and the portion of the second sub-insulating layer 123 at the bent portion 1a.
- the multi-layer conductive layer 11 of the flexible circuit board 1 when the multi-layer conductive layer 11 of the flexible circuit board 1 does not include the first wiring layer 114 and the second wiring layer 115, but includes the multi-layer wiring layer 113, it can also be formed on the bending portion 1a.
- One or more air gaps enable the bending portion 1a of the flexible circuit board 1 to have better bending performance.
- the stacked structure of the flexible circuit board 1 can be implemented in a variety of ways.
- the bent portion 1a can form a single layer + double layer stacked structure through one air gap, or form a single layer + single layer + single layer stacked structure through two air gaps. layer structure.
- the bent portion 1a can form a double-layer+double-layer stacked structure through one air gap, or form a single-layer+double-layer+single-layer stacked structure through two air gaps. , or form a laminated structure of single layer + single layer + single layer + single layer through three air gaps.
- the embodiment of the present application does not strictly limit the number and specific stacked structure of the conductive layers 11 of the flexible circuit board 1 .
- FIG. 13 is a schematic diagram of the internal structure of the flexible circuit board 1 provided by the embodiment of the present application in other embodiments.
- the flexible circuit board 1 has a bending portion 1a and a welding portion 1b connecting the bending portion 1a.
- the flexible circuit board 1 can be an integral structural member, and the bending portion 1a and the welding portion 1b are the flexible circuit board 1 of two parts.
- the bending portion 1a can be deformed such as bending, so that the flexible circuit board 1 can be deformed.
- the flexible circuit board 1 can weld other components (such as a printed circuit board) through the welding portion 1b, that is, the welding portion 1b is used to connect other components to achieve electrical connection with other components.
- the number of welding parts 1b can be two.
- the two welding parts 1b can be connected to both ends of the bending part 1a respectively.
- the two welding parts 1b can be welded to different components respectively.
- the flexible circuit board 1 can realize different components. electrical connection between them.
- the surface layers on both sides of the welding portion 1b of the flexible circuit board 1 form a welding structure.
- one surface layer of the welding portion 1b of the flexible circuit board 1 forms a welding structure, and the other side does not.
- the flexible circuit board 1 includes a plurality of conductive layers 15, a plurality of insulating layers 16 and a first protective layer 171.
- the plurality of conductive layers 15, a plurality of insulating layers 16 and the first protective layer 171 are stacked. Two adjacent conductive layers There is an insulating layer 16 between them.
- the conductive layer 15 is used to achieve electrical conduction, and the conductive layer 15 can be made of conductive materials such as copper foil.
- the insulating layer 16 is used to achieve an insulating effect, and the insulating layer 16 can be made of insulating materials such as polyimide (PI).
- PI polyimide
- an adhesive layer may be provided between the conductive layer 15 and the insulating layer 16 to achieve mutual fixation, or the adhesive layer may not be provided and directly contact and fix each other; conductive layers at different positions Whether an adhesive layer is provided between the layer 15 and the adjacent insulating layer 16 may be the same or different.
- the embodiment of the present application does not impose strict requirements on the fixing method and fixing structure of the plurality of conductive layers 15 and the plurality of insulating layers 16. limited.
- the plurality of conductive layers 15 include soldering layers 151 and wiring layers 152 .
- the welding layer 151 is a conductive layer, and the welding layer 151 is used to weld other components to achieve electrical connection between the flexible circuit board 1 and other components.
- the welding layer 151 is located at the welding part 1b, and the welding layer 151 is one of the surface layers of the welding part 1b.
- the soldering layer 151 is composed of a plurality of soldering pads 1511 spaced apart from each other. The plurality of pads 1511 may be arranged in an array or in other arrangements.
- the wiring layer 152 is a conductive layer, and at least wiring is arranged in the wiring layer 152 to realize electrical signal transmission through the wiring.
- the electrical signal may include, but is not limited to, one or more of a power signal, a ground signal, and a data signal.
- the wiring layer 152 is located on one side of the soldering layer 151 and extends from the soldering portion 1b to the bending portion 1a.
- the number of wiring layers 152 may be one or more. When the number of wiring layers 152 is multiple, an insulation layer is provided between two adjacent wiring layers 152 .
- the pad 1511 is connected to the wiring layer 152 through the via conductor 18 .
- the through-hole conductor 18 may be a conductive layer structure formed on the wall of the through-hole, or a conductive pillar structure filled in the through-hole, which is not strictly limited in the embodiment of the present application.
- the wiring layer 152 may include a conductor block 1521 and a trace 1522.
- the conductor block 1521 is located at the welding part 1b.
- One end of the trace 1522 is connected to the conductor block 1521 and the other end extends to the bending part 1a.
- the soldering pad 1511 of the soldering layer 151 is connected to the conductor block 1521 through the through-hole conductor 18 , and the soldering pad 1511 can be electrically connected to other parts or other components of the flexible circuit board 1 through the conductor block 1521 and the trace 1522 .
- the first protective layer 171 is located on the side of the wiring layer 152 facing away from the welding layer 151.
- the first protective layer 171 extends from the welding part 1b to the bending part 1a.
- the part of the first protective layer 171 located on the welding part 1b forms the welding part 1b.
- the other surface layer of the bent portion 1a forms one of the surface layers of the bent portion 1a.
- the first protective layer 171 is also an insulating layer, which can also be called a solder resist layer, and is used to protect the internal structure of the flexible circuit board 1 .
- the welding part 1b does not have a welding structure on the side of the first protective layer 171.
- the first protective layer 171 does not need to be provided with solder resist openings and other structures at the welding part 1b and can be a continuous and complete surface structure.
- the plurality of insulating layers 16 may include a first insulating layer 161 located between the welding layer 151 and the adjacent wiring layer 152 and extending from the welding portion 1b to the bending portion 1a.
- the portion of the layer 161 located at the bent portion 1a forms another surface layer of the bent portion 1a.
- the portion of the first insulating layer 161 located at the soldering portion 1 b is used to isolate the soldering layer 151 and the wiring layer 152 .
- the soldering layer 151 serves as one of the surface layers of the soldering part 1b, the soldering layer 151 only arranges the pads 1511 and does not arrange traces, so the soldering part 1b does not need to arrange a protective layer outside the soldering layer 151 (or called solder mask layer), there is no need to set up a solder mask window structure, so that the solder mask design can be realized.
- the pad spacing of the welding part 1b is not limited by the wiring and the solder mask window structure. The pad spacing Compared with the prior art, it is significantly reduced, thereby reducing the board area of the welding portion 1b, which is beneficial to the miniaturization of the flexible circuit board 1.
- the flexible circuit board 1 of the present application has multiple soldering pads separately provided on the soldering layer.
- the setting of the soldering layer may lead to an increase in the number of conductive layers, due to the small thickness of the conductive layer, for example, currently The thickness of the copper foil layer is usually 0.25 microns. Therefore, the increase in the overall thickness of the flexible circuit board 1 of the present application is small and controllable, and will not significantly affect the miniaturization of circuit board components and electronic equipment using the flexible circuit board 1. adverse effects or obstacles.
- the shape of the conductor block 1521 may be the same or similar to the shape of the pad 1511, for example, both are circular.
- the area of the conductor block 1521 is the same as the area of the pad 1511 .
- the pad spacing is reduced to 0.55mm.
- the pad spacing of the present application can be reduced by about 22% compared to the traditional solution.
- the flexible circuit board 1 of the present application has a smaller board area of the welding portion 1b than the traditional product. It can be reduced by about 40%, and the board area of the welding portion 1b is greatly reduced, which is beneficial to the miniaturization of the flexible circuit board 1 and the circuit board components and electronic equipment using the flexible circuit board 1.
- the area of the conductor block 1521 may be smaller than the area of the pad 1511 .
- the soldering pad 1511 since the soldering pad 1511 is connected to the conductor block 1521 through the through-hole conductor 18, the position of the soldering pad 1511 is limited by the arrangement of the conductive block 1521.
- the conductor By making the area of the conductive block 1521 smaller than the area of the soldering pad 1511, the conductor When the area of the block 1521 meets the internal connection requirements (that is, connected to the through-hole conductor 18), it can be set to a smaller value, so that when the wiring layer 152 meets the wiring arrangement, the two adjacent conductors
- the distance between the blocks 1521 can be smaller, so that the center distance between two adjacent pads 1511 can be smaller, so that the distance between the pads of the welding part 1b can be further reduced, which is beneficial to the miniaturization of the flexible circuit board 1 .
- FIG. 14 is a schematic diagram of the internal structure of the flexible circuit board 1 provided by the embodiment of the present application in other embodiments.
- the flexible circuit board 1 shown in this embodiment can include most of the technical features in the previous embodiments. The following mainly describes the differences between the two, and the same parts between the two will not be described again.
- the number of wiring layers 152 of the flexible circuit board 1 may be multiple layers, such as two layers, three layers, four layers, etc. This embodiment takes two layers as an example for description and illustration.
- the two conductor blocks 1521 correspondingly connected to the two adjacent bonding pads 1511 may be located on different wiring layers 152 .
- the plurality of conductor blocks 1521 connected by the plurality of bonding pads 1511 may be distributed and located in different wiring layers 152 .
- the conductor blocks 1521 connected to at least two of the plurality of bonding pads 1511 may be located on different wiring layers 152 .
- the plurality of bonding pads 1511 include a first bonding pad and a second bonding pad. The first bonding pad is connected to the first conductor block.
- the first conductor block is located on the first wiring layer.
- the pad connects to the second conductor block, which is located on the second trace layer.
- the traces 1522 connected to the conductor blocks 1521 need to be arranged.
- the wiring layer 152 of the flexible circuit board 1 will have high wiring arrangement requirements, which will lead to tight space of the wiring layer 152 and difficulty in wiring arrangement.
- the conductor blocks 1521 connected to at least two of the plurality of bonding pads 1511 are located in different wiring layers 152, the wiring 1522 connected to the conductor blocks 1521 can also be dispersedly arranged in different wiring layers. 152, thereby reducing the wiring difficulty of the wiring layer 152 and improving the wiring flexibility.
- the welding portion 1 b of the flexible circuit board 1 is provided with multiple punched areas, and the plurality of through-hole conductors 18 pass through the multiple punched areas in one-to-one correspondence.
- the soldering layer 151 and the wiring layer 152 are each provided with a plurality of corresponding punched areas.
- the above-mentioned punched area includes both the space occupied by the through-hole conductor 18 and the space located within a certain range around the through-hole conductor 18 .
- multiple perforated areas of the soldering layer 151 are provided with multiple pads 1511 , and multiple through-hole conductors 18 pass through the multiple pads 1511 and connect the pads 1511 .
- the number of wiring layers 152 may be one or more layers. Each wiring layer 152 is provided with a plurality of punched areas. Each punched area is provided with a support block, and multiple through-hole conductors 18 pass through them one by one. Through a plurality of punched areas, via conductors 18 pass through and connect the support blocks. For example, as shown in FIG. 13 , when the number of wiring layers 152 is one layer and multiple conductor blocks 1521 connected by multiple pads 1511 are located in this layer of wiring layer 152 , The support block of each punched area is a conductor block 1521, and the through-hole conductor 18 passes through the conductor block 1521 and is connected to the conductor block 1521. As shown in FIG.
- the multiple conductor blocks 1521 located on each wiring layer 152 can be a conductor block 1521 or a bottom pad 1523 (target pad). That is, when the wiring layer 152 is multi-layered, if the conductor block 1521 is not arranged in the perforated area of the wiring layer 152, the bottom pad 1523 is arranged. Among them, the bottom pad 1523 and the conductor block 1521 are essentially conductor structures.
- the bottom pad 1523 is not connected to the wiring and is a suspended structure in the transmission circuit of the flexible circuit board 1, while the conductor block 1521 is connected to the wiring 1522 , as part of the transmission circuit.
- the area of the bottom pad 1523 may be greater than, less than, or equal to the area of the conductor block 1521, which is not strictly limited in the embodiment of the present application.
- each wiring layer 152 of the flexible circuit board 1 is provided with a support block (conductor block 1521 or bottom pad 1523), the overall support of each perforated area of the flexible circuit board 1 is The structure is stable and not prone to collapse, and the thickness of multiple punched areas of the flexible circuit board 1 can be kept consistent, which is conducive to batch drilling and filling of metal, and improves the production efficiency and yield of the flexible circuit board 1 .
- the number of wiring layers 152 is multiple, some of the through-hole conductors 18 of the plurality of through-hole conductors 18 may not pass through all of the wiring layers 152 , but may pass through part of the wiring layers 152 .
- the number of wiring layers 152 is two. Some of the through-hole conductors 18 pass through the two wiring layers 152 , and some of the through-hole conductors 18 pass through one of the wiring layers 152 . In this case, the number of punched areas of different wiring layers 152 may be different, and the number of support blocks arranged in the punched areas may be different.
- the portion of the wiring layer 152 that is not penetrated by the through-hole conductor 18 may have a support area, and the support area corresponds to other wiring layers that are passed through by the through-hole conductor 18 152 is provided in the punched area, and the supporting area can also be provided with supporting blocks to improve the supporting strength of the area of the flexible circuit board 1 corresponding to the through-hole conductor 18 .
- the thickness of the bent portion 1a of the flexible circuit board 1 is very small. It is small and can ensure bending performance, so that the flexible circuit board 1 can meet diverse installation environments and has better reliability. In some other embodiments, the number of wiring layers 152 of the flexible circuit board 1 can also be larger to meet wiring requirements such as multiple transmission channels.
- FIG. 15 is a schematic diagram of the internal structure of the flexible circuit board 1 provided by the embodiment of the present application in other embodiments.
- the flexible circuit board 1 shown in this embodiment may include most of the technical features in the previous embodiments. The following mainly describes the differences between the two, and the same parts between the two will not be described again.
- the plurality of conductive layers 15 further include a wiring layer 153 located at the bent portion 1a, and the wiring layer 153 and the welding layer 151 are arranged in the same layer.
- the wiring layer 153 is a conductive layer, and at least one or more wires are arranged to realize electrical signal transmission through the wires.
- the wiring layer 153 is made of conductive materials such as copper foil.
- the wiring layer 153 may be electrically connected to the wiring layer 152 .
- the flexible circuit board 1 also includes a second protective layer 172.
- the second protective layer 172 is located on the side of the wiring layer 153 facing away from the wiring layer 152.
- the second protective layer 172 is located on the bending portion 1a and is the other side of the bending portion 1a. surface layer.
- the second protective layer 172 is an insulating layer used to protect the internal structure of the flexible circuit board 1 and may also be called a solder resist layer.
- both the wiring layer 153 and the wiring layer 152 can be used to arrange wiring, so the flexible circuit board 1 can better meet the needs of many users. Cabling requirements such as transmission channels.
- FIG. 16 is a schematic diagram of the internal structure of the flexible circuit board 1 provided by the embodiment of the present application in other embodiments.
- the flexible circuit board 1 shown in the embodiment may include most of the technical features in the previous embodiments. The differences between the two will be mainly described below, and the identical parts between the two will not be described again.
- At least one insulating layer 16 of the flexible circuit board 1 can form an air gap (Airgap) in the bending portion 1a, that is, a flexible circuit
- the bent portion 1a of the board 1 forms one or more air gaps, so that the structures on both sides of the air gap of the flexible circuit board 1 can move relatively independently to improve the bending performance of the bent portion 1a of the flexible circuit board 1.
- the flexible circuit board 1 may have a three-layer structure.
- the plurality of conductive layers 15 of the flexible circuit board 1 may include a wiring layer 153 and two wiring layers 152.
- the insulating layer 16 located between the two wiring layers 152 may An air gap 161 is formed in the bent portion 1a.
- the insulating layer 16 located between the two wiring layers 152 may include a first sub-insulating layer 162 and a second sub-insulating layer 163.
- the first sub-insulating layer 162 is located at the welding portion 1b and the second sub-insulating layer 163
- the part on the welding part 1b can be pressed and fixed by the adhesive on it, and the adhesive on the part of the first sub-insulating layer 162 on the bending part 1a and the part of the second sub-insulating layer 163 on the bending part 1a can be removed. Or omitted, an air gap 161 is formed between the portion of the first sub-insulating layer 162 at the bent portion 1a and the portion of the second sub-insulating layer 163 at the bent portion 1a.
- An air gap may also be formed between the wiring layer 153 and the wiring layer 152 .
- one or more air gaps can also be formed in the bending portion 1a, so that The bending portion 1a of the flexible circuit board 1 has better bending performance.
- the stacked structure of the flexible circuit board 1 can be implemented in various ways.
- the bent portion 1a can form a single layer + double layer stacked structure through one air gap, or form a single layer + single layer + single layer stacked structure through two air gaps. layer structure.
- the bent portion 1a can form a double-layer+double-layer stacked structure through one air gap, or form a single-layer+double-layer+single-layer stacked structure through two air gaps. , or form a laminated structure of single layer + single layer + single layer + single layer through three air gaps.
- the embodiment of the present application does not strictly limit the number and specific stacked structure of the conductive layers 15 of the flexible circuit board 1 .
- the flexible circuit board 1 may also include two wiring layers 153, such as a first wiring layer and a second wiring layer.
- the first wiring layer and the second wiring layer are both located at the bending portion 1a.
- the wiring layer and the soldering layer 151 are arranged on the same layer, and the second wiring layer is located on the side of the first protective layer 171 facing away from the wiring layer 152 .
- the flexible circuit board 1 may also include a second protective layer and a third protective layer.
- the second protective layer and the third protective layer are both located at the bending portion 1a.
- the second protective layer is located behind the first wiring layer and toward the wiring layer.
- the third protective layer is located on the side of the second wiring layer facing away from the wiring layer 152 .
- the portion of the first protective layer 171 located at the bent portion 1a is no longer the surface layer of the bent portion 1a, but is the internal layer structure of the bent portion 1a.
- the flexible circuit board 1 may include two welding parts 1b and a bending part 1a.
- the bending part 1a is connected between the two welding parts 1b.
- the two welding parts 1b weld different components.
- the flexible circuit board 1 The circuit board 1 implements electrical connections between different components.
- the flexible circuit board 1 may also include a welding part 1b, a bending part 1a, and may also include a connecting part.
- the bending part 1a may be connected between the welding part 1b and the connecting part, and the connecting part may be
- electrical connectors include but are not limited to board-to-board connectors (board to board, BTB), etc.
- BTB board-to-board connectors
- the flexible circuit board 1 can achieve electrical connection between the different components.
- the design of the welding portion 1b and the bending portion 1a of the flexible circuit board 1 may be the same as or similar to the previous embodiments, and will not be described again here.
- the flexible circuit board 1 may also include a welding part 1b, a bending part 1a and a mounting part.
- the bending part 1a may be connected between the welding part 1b and the mounting part.
- the mounting part may be For mounting components, the components can be chips and/or auxiliary components of the chip, etc.
- the welding portion 1 b of the flexible circuit board 1 is fixed and electrically connected to other components, the components mounted on the mounting portion of the flexible circuit board 1 are electrically connected to the corresponding components.
- the flexible circuit board 1 and the components together form a Flexible Printed Circuit Assemble (FPCA).
- FPCA Flexible Printed Circuit Assemble
- the design of the welding portion 1b and the bending portion 1a of the flexible circuit board 1 may be the same as or similar to the previous embodiments, and will not be described again here.
- Figure 17 is a schematic structural diagram of the circuit board assembly 10 provided by the embodiment of the present application in some embodiments.
- Figure 18 is a schematic structural diagram of the circuit board assembly 10 shown in Figure 17 from another angle.
- FIG. 19 is a schematic cross-sectional view of a partial structure of the circuit board assembly 10 shown in FIG. 17 .
- the circuit board assembly 10 includes a circuit board 2 and a flexible circuit board 1.
- the welding portion 1b of the flexible circuit board 1 welds the circuit board 2, and the bending portion 1a can be deformed according to the installation environment.
- the circuit board 2 may be a printed circuit board or a flexible circuit board.
- a plurality of soldering pads 21 are provided on the circuit board 2.
- the plurality of soldering pads 21 of the circuit board 2 are in contact with the soldering pad structure of the welding portion 1b of the flexible circuit board 1 (that is, the first soldering pad 1111 and the second soldering pad 1121). correspond.
- the welding part 1b can be fixed and electrically connected to the circuit board 2 through surface mount technology (SMT), hot bar welding (Hotbar) process or other methods.
- SMT surface mount technology
- Hotbar hot bar welding
- FIG. 9 the structure of the flexible circuit board 1 shown in Figure 9 is used for illustration in Figure 19.
- the flexible circuit board 1 of the circuit board assembly 10 in this embodiment can also use the two surface layers of the welding portion 1b in the previous embodiment.
- Other flexible circuit board structures with welding structures such as the structures shown in Figure 5, Figure 8, Figure 11 or Figure 12.
- the welding pads of the welding part 1b (that is, the first welding pad 1111 and the second welding pad 1121) can be connected to the circuit board in advance.
- Solder paste and flux are preset on the pads 21 of 2, and then heated by a pulse thermal head to realize welding between the pads, thereby achieving electrical conduction between the flexible circuit board 1 and the circuit board 2.
- the flexible circuit board 1 can be used as a component to be welded to the circuit board 2, or the circuit board 2 can be used as a component to be welded to the flexible circuit. Board 1, thereby achieving electrical conduction between the flexible circuit board 1 and the circuit board 2.
- the pads (i.e., the first pad 1111 and the second pad 1121) of the welding portion 1b of the flexible circuit board 1 have a protruding surface structure, solder paste collapse and short circuit can be avoided during the welding process. , ensuring that the solder joints have a certain height, thereby improving the welding quality and reliability.
- FIG. 20 is a schematic structural diagram of the circuit board assembly 10 provided by the embodiment of the present application in other embodiments.
- FIG. 21 is a partial structural schematic diagram of the circuit board assembly 10 shown in FIG. 20 .
- the circuit board assembly 10 includes a circuit board 2 and a flexible circuit board 1.
- the welding portion 1b of the flexible circuit board 1 welds the circuit board 2, and the bending portion 1a can be deformed according to the installation environment.
- the circuit board 2 may be a printed circuit board or a flexible circuit board.
- the circuit board 2 is provided with a plurality of soldering pads 21 , and the plurality of soldering pads 21 on the circuit board 2 are structurally corresponding to the soldering pads 1511 of the welding portion 1 b of the flexible circuit board 1 .
- the welding part 1b can be fixed and electrically connected to the circuit board 2 through surface mount technology (SMT) or other methods.
- SMT surface mount technology
- FIG. 14 the structure of the flexible circuit board 1 shown in FIG. 14 is used for illustration in FIG. Welding structure, other flexible circuit board structures without a welding structure on another surface layer, such as the structures shown in Figure 13, Figure 15 or Figure 16.
- the flexible circuit board 1 when the welding portion 1b of the flexible circuit board 1 is fixed to the circuit board 2 through surface mounting technology, the flexible circuit board 1 can be used as a component to be welded to the circuit board 2, or the circuit board 2 can be used as a component to be welded to the circuit board 2.
- the circuit board assembly 10 may also include one or more components, and the one or more components may be soldered to the circuit board 2 and/or soldered to the circuit board 2 .
- Flexible circuit board1 when the circuit board 2 is a printed circuit board and components are mounted on the circuit board 2, the circuit board 2 and the components can jointly form a printed circuit board assembly (Printed Circuit Board Assemble, PCBA).
- the circuit board assembly 10 may also include an electrical connector, which may fix and electrically connect the flexible circuit board 1 , so that the flexible circuit board 1 may also Electrically connected to other components through electrical connectors.
- circuit board assembly 10 Some embodiments of the circuit board assembly 10 are schematically described below.
- FIG. 22 is a schematic structural diagram of the circuit board assembly 10 provided by the embodiment of the present application in some embodiments.
- the circuit board assembly 10 includes a first circuit board 22 , a second circuit board 23 , a flexible circuit board 1 , a first component 31 and a second component 32 .
- the flexible circuit board 1 includes two welding parts 1b and a bending part 1a connecting the two welding parts 1b.
- the two welding parts 1b of the flexible circuit board 1 weld the first circuit board 22 and the second circuit board 23 respectively.
- the structures of the welding portion 1b and the bending portion 1a of the flexible circuit board 1 can refer to any structure in the previous embodiments.
- the first circuit board 22 may be a printed circuit board or a flexible circuit board
- the second circuit board 23 may be a printed circuit board or a flexible circuit board.
- the number of the first component 31 may be one or more, and the first component 31 is fixed and electrically connected to the first circuit board 22 .
- the number of the second component 32 may be one or more, and the second component 32 is fixed and electrically connected to the second circuit board 23 .
- the flexible circuit board 1 is used to realize electrical connection between the first component 31 and the second component 32 .
- the first circuit board 22 and the second circuit board 23 can be stacked, and the bending portion 1a of the flexible circuit board 1 is bent, so that the circuit board assembly 10 forms a sandwich stack structure, and the overall space occupied by the circuit board assembly 10 is smaller. , the required installation space is smaller, which is helpful to reduce the difficulty of installation and improve the scope of application.
- the first circuit board 22 and the second circuit board 23 may also form other relative positional relationships, such as a staggered arrangement, etc.
- FIG. 23 is a schematic structural diagram of the circuit board assembly 10 provided by the embodiment of the present application in other embodiments.
- the circuit board assembly 10 includes a first circuit board 22, a second circuit board 23, a flexible circuit board 1, a first electrical connector 41, a second electrical connector 42, a first component 31 and a second component.
- Device 32 The flexible circuit board 1 includes a welding portion 1b, a connecting portion 1c, and a bending portion 1a connecting the welding portion 1b and the connecting portion 1c.
- the structure of the welding portion 1b and the bending portion 1a of the flexible circuit board 1 can refer to any of the previous embodiments. a structure.
- the first circuit board 22 may be a printed circuit board or a flexible circuit board.
- the number of the first component 31 may be one or more, and the first component 31 is fixed and electrically connected to the first circuit board 22 .
- the soldering portion 1b of the flexible circuit board 1 is soldered Connect to the first circuit board 22.
- the number of the second component 32 may be one or more, and the second component 32 is fixed and electrically connected to the second circuit board 23 .
- the first electrical connector 41 and the second electrical connector 42 may be male and female respectively, and the male and female are paired with each other.
- the first electrical connector 41 and the second electrical connector 42 may be board-to-board electrical connectors or the like.
- the first electrical connector 41 is fixed and electrically connected to the connection portion 1 c of the flexible circuit board 1
- the second electrical connector 42 is fixed and electrically connected to the second circuit board 23 .
- the first electrical connector 41 is fixed and electrically connected to the second electrical connector 42 , and the flexible circuit board 1 is used to realize the electrical connection between the first component 31 and the second component 32 .
- the first circuit board 22 and the second circuit board 23 can be stacked, and the bending portion 1a of the flexible circuit board 1 is bent, so that the circuit board assembly 10 forms a sandwich stack structure, and the overall space occupied by the circuit board assembly 10 is smaller. , the required installation space is smaller, which is helpful to reduce the difficulty of installation and improve the scope of application.
- the first circuit board 22 and the second circuit board 23 may also form other relative positional relationships, such as a staggered arrangement, etc.
- FIG. 24 is a schematic structural diagram of the circuit board assembly 10 provided by the embodiment of the present application in other embodiments.
- the circuit board assembly 10 includes a circuit board 2 , a flexible circuit board 1 , a first component 31 and a second component 32 .
- the flexible circuit board 1 includes a welding part 1b, a mounting part 1d, and a bending part 1a connecting the welding part 1b and the mounting part 1d.
- the structures of the welding part 1b and the bending part 1a of the flexible circuit board 1 can be referred to the previous embodiments. any structure.
- the circuit board 2 can be a printed circuit board or a flexible circuit board.
- the number of the first component 31 may be one or more, and the first component 31 is fixed and electrically connected to the circuit board 2 .
- the soldering part 1b of the flexible circuit board 1 solders the circuit board 2.
- the number of the second component 32 may be one or more.
- the second component 32 is fixed and electrically connected to the mounting part 1d of the flexible circuit board 1 .
- the flexible circuit board 1 is used to realize electrical connection between the first component 31 and the second component 32 .
- An embodiment of the present application also provides an electronic device, including a housing and a circuit board assembly.
- the circuit board assembly can adopt any structure in the previous embodiments, and the circuit board assembly is installed inside the housing.
- the electronic device may be, but is not limited to, a mobile phone, a tablet (pad), a portable game console, a personal digital assistant (PDA), a notebook computer, an ultra-mobile personal computer (UMPC), a handheld Electronic products such as computers, netbooks, in-vehicle media playback devices, wearable electronic devices, virtual reality (VR) terminal devices, or augmented reality (AR) terminal devices.
- PDA personal digital assistant
- UMPC ultra-mobile personal computer
- handheld Electronic products such as computers, netbooks, in-vehicle media playback devices, wearable electronic devices, virtual reality (VR) terminal devices, or augmented reality (AR) terminal devices.
- VR virtual reality
- AR augmented reality
- the first circuit board 22 and the second circuit board 23 can be the main board and the secondary board respectively.
- the first component 31 may include a processor, etc.
- the second component 32 may include a radio frequency chip, etc.
- the first circuit board 22 may be the circuit board of the heart rate module.
- the first component 31 may include a heart rate detection sensor, etc.
- the second circuit board 23 may be a mainboard
- the second component 32 may include a processor, etc.
- the circuit board 2 can be the main board
- the first component 31 can include a processor, etc.
- the second component 32 may include a microphone (Microphone, MIC) and/or its accessories.
- circuit board assemblies are diversified, and the applications of circuit board assemblies in electronic devices of different shapes, categories, and sizes are also diversified, which are not strictly limited in the embodiments of the present application.
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Abstract
本申请公开了一种柔性电路板、电路板组件及电子设备。柔性电路板具有弯折部和连接弯折部的焊接部;柔性电路板包括多个导电层和多个绝缘层,相邻的两层导电层之间均设有绝缘层;多个导电层包括第一焊接层、第二焊接层及走线层;第一焊接层和第二焊接层均位于焊接部,第一焊接层为焊接部的其中一个表层,第一焊接层由多个彼此间隔设置的第一焊盘组成,第二焊接层为焊接部的另一个表层,第二焊接层由多个彼此间隔设置的第二焊盘组成;走线层位于第一焊接层与第二焊接层之间,且自焊接部延伸至弯折部,第一焊盘和第二焊盘通过通孔导体相连,且连接走线层。柔性电路板的焊接部的焊盘间距较小,能够减小焊接部的板面面积,有利于小型化。
Description
本申请要求于2022年06月30日提交中国专利局、申请号为202210758071.2、申请名称为“柔性电路板、电路板组件及电子设备”的中国专利申请的优先权,其全部内容通过引用结合在本申请中。
本申请涉及电路连接结构技术领域,尤其涉及柔性电路板、电路板组件及电子设备。
当前,手机等电子设备不断发展,这些电子设备中印制电路板(printed circuit board,PCB,也可称为印制电路板)和柔性电路板(flexible printed circuit,FPC)的应用十分普遍,通过软-硬板板间互联(FPC on board,FOB)技术可将柔性电路板和印制电路板焊接在一起,以实现信号和/或电源传输。
然而,传统的柔性电路板的焊盘间距较大,导致柔性电路板及印制电路板均需要预留较大的焊接空间,电路板组件的体积较大,不易于电子设备的小型化和多功能化。
发明内容
本申请提供了一种柔性电路板,柔性电路板的焊接部的焊盘间距较小,能够减小焊接部的板面面积,有利于小型化。本申请还提供一种包括上述柔性电路板的电路板组件,以及一种包括上述电路板组件的电子设备。
第一方面,本申请提供一种柔性电路板,具有弯折部和连接弯折部的焊接部;柔性电路板包括多个导电层和多个绝缘层,相邻的两层导电层之间均设有绝缘层;多个导电层包括第一焊接层、第二焊接层及走线层。第一焊接层和第二焊接层均位于焊接部,第一焊接层为焊接部的其中一个表层,第一焊接层由多个彼此间隔设置的第一焊盘组成,第二焊接层为焊接部的另一个表层,第二焊接层由多个彼此间隔设置的第二焊盘组成;走线层位于第一焊接层与第二焊接层之间,且自焊接部延伸至弯折部,第一焊盘和第二焊盘通过通孔导体相连,通孔导体连接走线层。
在本申请中,由于第一焊接层和第二焊接层作为焊接部的两个表层,第一焊接层只排布第一焊盘、不排布走线,第二焊接层只排布第二焊盘、不排布走线,因此焊接部无需在第一焊接层和第二焊接层的外侧排布保护层(或称为阻焊层),也就无需设置阻焊开窗结构,从而可以实现去阻焊设计,焊接部的焊盘间距(也即相邻两个的第一焊盘的间距、相邻两个第二焊盘的间距)不受走线和阻焊开窗结构的限制,焊盘间距相较于现有技术明显降低,从而减小焊接部的板面面积,有利于柔性电路板的小型化。此外,柔性电路板的走线排布于走线层,为柔性电路板的内层结构,被绝缘层或保护层覆盖,有利于提升柔性电路板的线路可靠性。
此外,本申请柔性电路板相较于传统产品,将多个焊盘单独设于焊接层,虽然焊接层的设置可能导致了导电层数量的增加,但由于导电层的厚度很小,例如目前的铜箔层通常为0.25微米的厚度,因此本申请柔性电路板的整体厚度的增加量小、可控,不会对应用该柔性电路板的电路板组件及电子设备的小型化造成明显的不良影响或者障碍。
其中,通孔导体可以为形成于通孔孔壁的导电层结构,或者填充于通孔中的导体柱结构。
一种可能的实现方式中,走线层包括导体块和走线,导体块位于焊接部,走线的一端连接导体块,另一端延伸至弯折部,第一焊盘和第二焊盘通过通孔导体连接导体块。第一焊盘和第二焊盘通过通孔导体连接导体块,第一焊盘和第二焊盘可以经导体块及走线电连接至柔性电路板的其他部分或者其他部件。
一种可能的实现方式中,导体块的形状可以与第一焊盘形状相同或相近。
一种可能的实现方式中,导体块的面积与第一焊盘的面积相同。本申请焊盘间距相较于传统方案可以减小约22%,在多个焊盘阵列排布的结构下,本申请柔性电路板相较于传统产品,其焊接部的板面面积可以减小约40%,焊接部的板面面积大幅度减小,有利于柔性电路板的小型化,有助于应用该柔性电路板的电路板组件及电子设备的小型化。
一种可能的实现方式中,导体块的面积小于第一焊盘的面积。在本实现方式中,由于第一焊盘和第二焊盘通过通孔导体连接导体块,第一焊盘和第二焊盘的位置受限于导体块的设置,通过使导体块的面积小于第一焊盘的面积,使得导体块的面积满足内部连接需求(也即与通孔导体连接)的情况下,可以设置为
较小值,从而在走线层满足走线排布需求的情况下,相邻的两个导体块的间距可以较小,使得相邻两个第一焊盘的中心间距较小,从而能够进一步减小焊接部的焊盘间距,有利于柔性电路板的小型化。
一种可能的实现方式中,走线层的数量为多层,多个第一焊盘连接的多个导体块位于不同的走线层。其中,多个第一焊盘中的至少两个第一焊盘对应连接的导体块可以位于不同的走线层。
由于排布有导体块的走线层,均还需排布与导体块连接的走线,当与多个第一焊盘连接的多个导体块集中排布于柔性电路板的某一层走线层时,会导致该层走线层有较高的走线排布需求,继而导致该层走线层的空间紧张、走线排布困难。而当多个第一焊盘中的至少两个第一焊盘对应连接的导体块位于不同的走线层时,与导体块连接的走线同样可以分散排布于不同的走线层,从而降低了走线层的布线难度,提高了布线灵活度。
一种可能的实现方式中,走线层的数量为一层或多层,每层走线层均设有多个打孔区域,多个通孔导体一一对应地穿过各层走线层的多个打孔区域;每层走线层的多个打孔区域均设有支撑块,通孔导体穿过支撑块且连接支撑块;当走线层的数量为一层时,支撑块为导体块;或者,当走线层的数量为多层时,支撑块为导体块或底垫。
在本实现方式中,由于柔性电路板的每层走线层的打孔区域均设有支撑块(导体块或底垫),使得柔性电路板的各打孔区域的整体支撑结构稳定、不易发生坍塌,并且柔性电路板的多个打孔区域厚度能够保持一致,有利于批量打孔和填充金属,提高了柔性电路板的生产效率和良率。
一种可能的实现方式中,多个绝缘层包括第一绝缘层和第二绝缘层;第一绝缘层位于第一焊接层与相邻的走线层之间,且自焊接部延伸至弯折部,第一绝缘层位于弯折部的部分形成弯折部的一个表层;第二绝缘层位于第二焊接层与相邻的走线层之间,且自焊接部延伸至弯折部,第二绝缘层位于弯折部的部分形成弯折部的另一个表层。
一种可能的实现方式中,多个导电层还包括第一布线层和第二布线层,第一布线层和第二布线层均位于弯折部,第一布线层与第一焊接层同层设置,第二布线层与第二焊接层同层设置;柔性电路板还包括第一保护层和第二保护层,第一保护层和第二保护层均位于弯折部,第一保护层位于第一布线层背向走线层的一侧,第二保护层位于第二布线层背向走线层的一侧,第一保护层和第二保护层分别为弯折部的两个表层。
在本实现方式中,由于柔性电路板的弯折部设有第一布线层和第二布线层,第一布线层和第二布线层及走线层均可以用于排布走线,因此柔性电路板可以更好地满足多传输通道等布线需求。
一种可能的实现方式中,柔性电路板的至少一个绝缘层在弯折部形成空气间隙。此时,柔性电路板位于空气间隙两侧的结构可以相对独立地活动,以提升柔性电路板的弯折部的弯折性能。
第二方面,本申请还提供一种柔性电路板,具有弯折部和连接弯折部的焊接部;柔性电路板包括多个导电层、多个绝缘层以及第一保护层,相邻的两层导电层之间均设有绝缘层;多个导电层包括焊接层和走线层,焊接层位于焊接部,焊接层为焊接部的其中一个表层,焊接层由多个彼此间隔设置的焊盘组成,走线层位于焊接层的一侧,且自焊接部延伸至弯折部,焊盘通过通孔导体连接走线层;第一保护层位于走线层背向焊接层的一侧,第一保护层自焊接部延伸至弯折部,第一保护层位于焊接部的部分形成焊接部的另一个表层,位于弯折部的部分形成弯折部的其中一个表层。
在本实现方式中,由于焊接层作为焊接部的其中一个表层,焊接层只排布焊盘、不排布走线,因此焊接部无需在焊接层的外侧排布保护层(或称为阻焊层),也就无需设置阻焊开窗结构,从而可以实现去阻焊设计,焊接部的焊盘间距不受走线和阻焊开窗结构的限制,焊盘间距相较于现有技术明显降低,从而减小焊接部的板面面积,有利于柔性电路板的小型化。
此外,本申请柔性电路板相较于传统产品,将多个焊盘单独设于焊接层,虽然焊接层的设置可能导致了导电层数量的增加,但由于导电层的厚度很小,因此本申请柔性电路板的整体厚度的增加量小、可控,不会对应用该柔性电路板的电路板组件及电子设备的小型化造成明显的不良影响或者障碍。
一种可能的实现方式中,走线层包括导体块和走线,导体块位于焊接部,走线的一端连接导体块,另一端延伸至弯折部,焊盘通过通孔导体连接导体块。焊盘可以经导体块及走线电连接至柔性电路板的其他部分或者其他部件。
一种可能的实现方式中,导体块的形状可以与焊盘形状相同或相近。
一种可能的实现方式中,导体块的面积与焊盘的面积相同。本申请焊盘间距相较于传统方案可以减小约22%,在多个焊盘阵列排布的结构下,本申请柔性电路板相较于传统产品,其焊接部的板面面积可以减小约40%,焊接部的板面面积大幅度减小,有利于柔性电路板的小型化,有助于应用该柔性电路板的电路
板组件及电子设备的小型化。
一种可能的实现方式中,导体块的面积小于焊盘的面积。在本实现方式中,由于焊盘和第二焊盘通过通孔导体连接导体块,焊盘和第二焊盘的位置受限于导体块的设置,通过使导体块的面积小于焊盘的面积,使得导体块的面积满足内部连接需求(也即与通孔导体连接)的情况下,可以设置为较小值,从而在走线层满足走线排布需求的情况下,相邻的两个导体块的间距可以较小,使得相邻两个焊盘的中心间距较小,从而能够进一步减小焊接部的焊盘间距,有利于柔性电路板的小型化。
一种可能的实现方式中,走线层的数量为多层,多个焊盘连接的多个导体块位于不同的走线层。其中,多个焊盘中的至少两个焊盘对应连接的导体块可以位于不同的走线层。由于排布有导体块的走线层,均还需排布与导体块连接的走线,当与多个焊盘连接的多个导体块集中排布于柔性电路板的某一层走线层时,会导致该层走线层有较高的走线排布需求,继而导致该层走线层的空间紧张、走线排布困难。而当多个焊盘中的至少两个焊盘对应连接的导体块位于不同的走线层时,与导体块连接的走线同样可以分散排布于不同的走线层,从而降低了走线层的布线难度,提高了布线灵活度。
一种可能的实现方式中,走线层的数量为一层或多层,每层走线层均设有多个打孔区域,多个通孔导体一一对应地穿过各层走线层的多个打孔区域;每层走线层的多个打孔区域均设有支撑块,通孔导体穿过支撑块且连接支撑块;当走线层的数量为一层时,支撑块为导体块;或者,当走线层的数量为多层时,支撑块为导体块或底垫。
在本实现方式中,由于柔性电路板的每层走线层的打孔区域均设有支撑块(导体块或底垫),使得柔性电路板的各打孔区域的整体支撑结构稳定、不易发生坍塌,并且柔性电路板的多个打孔区域厚度能够保持一致,有利于批量打孔和填充金属,提高了柔性电路板的生产效率和良率。
一种可能的实现方式中,多个绝缘层包括第一绝缘层,第一绝缘层位于焊接层与相邻的走线层之间,且自焊接部延伸至弯折部,第一绝缘层位于弯折部的部分形成弯折部的另一个表层。
一种可能的实现方式中,多个导电层还包括布线层,布线层位于弯折部,布线层与焊接层同层设置;柔性电路板还包括第二保护层,第二保护层位于布线层背向走线层的一侧,第二保护层位于弯折部,为弯折部的另一个表层。
一种可能的实现方式中,柔性电路板的至少一个绝缘层在弯折部形成空气间隙。此时,柔性电路板位于空气间隙两侧的结构可以相对独立地活动,以提升柔性电路板的弯折部的弯折性能。
第三方面,本申请还提供一种电路板组件,包括电路板和上述任一项描述的柔性电路板,柔性电路板的焊接部焊接电路板。
其中,由于柔性电路板的焊接部的焊盘为凸出表面的结构,能够在焊接过程中避免锡膏坍塌短路,保证焊点具有一定高度,从而改善焊接质量和可靠性。
一种可能的实现方式中,电路板组件包括第一电路板、第二电路板、柔性电路板、第一元器件及第二元器件。柔性电路板包括两个焊接部和连接两个焊接部的弯折部,柔性电路板的两个焊接部分别焊接第一电路板和第二电路板。柔性电路板的焊接部及弯折部的结构可以采用前述任一种结构。其中,第一电路板可以为印制电路板或者柔性电路板,第二电路板可以为印制电路板或者柔性电路板。第一元器件的数量可以为一个或多个,第一元器件固定且电连接第一电路板。第二元器件的数量可以为一个或多个,第二元器件固定且电连接第二电路板。柔性电路板用于实现第一元器件与第二元器件之间的电连接。
其中,第一电路板和第二电路板可以堆叠设置,柔性电路板的弯折部发生弯折,使得电路板组件形成三明治堆叠结构,电路板组件的整体占用空间较小,所需的安装空间较小,有利于降低安装难度,提高适用范围。在其他一些实现方式中,第一电路板和第二电路板也可以形成其他相对位置关系,例如错位排布等。
一些实现方式中,电路板组件包括第一电路板、第二电路板、柔性电路板、第一电连接器、第二电连接器、第一元器件及第二元器件。柔性电路板包括焊接部、连接部及连接焊接部与连接部的弯折部,柔性电路板的焊接部及弯折部的结构可以采用前述任一种结构。第一电路板可以为印制电路板或者柔性电路板。第一元器件的数量可以为一个或多个,第一元器件固定且电连接第一电路板。柔性电路板的焊接部焊接第一电路板。第二元器件的数量可以为一个或多个,第二元器件固定且电连接第二电路板。第一电连接器和第二电连接器可以分别为公头和母头,公头和母头互相配对。第一电连接器和第二电连接器可以为板对板电连接器等。第一电连接器固定且电连接柔性电路板的连接部,第二电连接器固定且电连接第二电路板。第一电连接器固定且电连接第二电连接器,柔性电路板用于实现第一元器件与第二元器件之间的电连接。
其中,第一电路板和第二电路板可以堆叠设置,柔性电路板的弯折部发生弯折,使得电路板组件形成
三明治堆叠结构,电路板组件的整体占用空间较小,所需的安装空间较小,有利于降低安装难度,提高适用范围。在其他一些实现方式中,第一电路板和第二电路板也可以形成其他相对位置关系,例如错位排布等。
一些实现方式中,电路板组件包括电路板、柔性电路板、第一元器件及第二元器件。柔性电路板包括焊接部、贴装部及连接焊接部与贴装部的弯折部,柔性电路板的焊接部及弯折部的结构可以采用前述任一种结构。电路板可以为印制电路板或者柔性电路板。第一元器件的数量可以为一个或多个,第一元器件固定且电连接电路板。柔性电路板的焊接部焊接电路板。第二元器件的数量可以为一个或多个,第二元器件固定且电连接柔性电路板的贴装部。柔性电路板用于实现第一元器件与第二元器件之间的电连接。
第四方面,本申请还提供一种电子设备,包括壳体及上述电路板组件,电路板组件安装于壳体的内部。
图1是传统的柔性电路板的结构示意图;
图2是图1所示柔性电路板沿A-A处剖开的截面结构示意图;
图3是图1所示柔性电路板的部分结构示意图;
图4是本申请实施例提供的柔性电路板在一些实施例中的结构示意图;
图5是图4所示柔性电路板沿B-B处剖开的截面结构示意图;
图6是图4所示柔性电路板的部分结构示意图;
图7是图5所示走线层的部分结构示意图;
图8是本申请实施例提供的柔性电路板在另一些实施例中的内部结构示意图;
图9是本申请实施例提供的柔性电路板在另一些实施例中的内部结构示意图;
图10是图9所示柔性电路板的部分结构示意图;
图11是本申请实施例提供的柔性电路板在另一些实施例中的内部结构示意图;
图12是本申请实施例提供的柔性电路板在另一些实施例中的内部结构示意图;
图13是本申请实施例提供的柔性电路板在另一些实施例中的内部结构示意图;
图14是本申请实施例提供的柔性电路板在另一些实施例中的内部结构示意图;
图15是本申请实施例提供的柔性电路板在另一些实施例中的内部结构示意图;
图16是本申请实施例提供的柔性电路板在另一些实施例中的内部结构示意图;
图17是本申请实施例提供的电路板组件在一些实施例中的结构示意图;
图18是图17所示电路板组件在另一角度的结构示意图;
图19是图17所示电路板组件的部分结构示意图;
图20是本申请实施例提供的电路板组件在另一些实施例中的结构示意图;
图21是图20所示电路板组件的部分结构示意图;
图22是本申请实施例提供的电路板组件在一些实施例中的结构示意图;
图23是本申请实施例提供的电路板组件在另一些实施例中的结构示意图;
图24是本申请实施例提供的电路板组件在另一些实施例中的结构示意图。
下面将结合附图对本申请实施例中的技术方案进行描述。其中,在本申请实施例的描述中,除非另有说明,“/”表示或的意思,例如,A/B可以表示A或B;文本中的“和/或”仅仅是一种描述关联对象的关联关系,表示可以存在三种关系,例如,A和/或B,可以表示:单独存在A,同时存在A和B,单独存在B这三种情况,另外,在本申请实施例的描述中,“多个”是指两个或多于两个,也即“多个”为至少两个。
在本申请实施例的描述中,需要说明的是,除非另有明确的规定和限定,术语“安装”、“连接”、“设置在……上”应做广义理解,例如,“连接”可以是可拆卸地连接,也可以是不可拆卸地连接;可以是直接连接,也可以通过中间媒介间接连接。
术语“第一”、“第二”等用词仅用于描述目的,而不能理解为暗示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此,限定有“第一”、“第二”的特征可以明示或者隐含地包括一个或者更多个该特征。
请结合参阅图1至图3,图1是传统的应用于软-硬板板间互联结构中的柔性电路板20的结构示意图,图2是图1所示柔性电路板20沿A-A处剖开的截面结构示意图,图3是图1所示柔性电路板20的部分结构示意图。
在传统的柔性电路板20中,柔性电路板20包括两个焊接部20a和连接两个焊接部20a的弯折部20b,弯折部20b能够发生弯折等变形。柔性电路板20包括依次堆叠设置的第一保护层201、第一导电层202、绝缘层203、第二导电层204及第二保护层205。其中,第一保护层201、第二保护层205也为绝缘层,也可以称为阻焊层,第一保护层201和第二保护层205为柔性电路板20的两个表层。第一导电层202包括多个焊盘2021和多根走线2022,第一保护层201设有用于露出多个焊盘2021的多个开窗2011。
其中,相邻两个焊盘2021之间通常排布有一根或多根走线2022,当相邻两个焊盘2021之间布设一根走线2022时,相邻两个焊盘2021的中心间距包括:两个焊盘2021的半径R,两个第一保护层201的开窗2011边缘与焊盘2021之间的间距S,两个开窗2011边缘与走线2022之间的间距S1、S2以及走线2022宽度W,也即相邻两个焊盘2021的中心间距=2R+2S+S1+S2+W。例如,一些产品中,以当前柔性电路板20的业界的普遍加工能力,以最小值为例,R为0.15mm,S为0.075mm,S1、S2为0.075mm,W为0.1mm,则焊盘间距达到0.7mm以上,焊盘间距较大,导致焊接部20a的板面尺寸较大,柔性电路板20的体积较大。
本申请提供一种柔性电路板,柔性电路板通过在焊接部增设只排布焊盘、不排布走线的焊接层,采用去阻焊设计,使得焊接层的焊盘间距能够不受走线及阻焊开窗等结构的限制,焊盘间距能够明显降低,从而减小焊接部的板面面积,有利于柔性电路板的小型化。本申请还提供一种包括上述柔性电路板的电路板组件,以及一种包括上述电路板组件的电子设备。
请结合参阅图4至图6,图4是本申请实施例提供的柔性电路板1在一些实施例中的结构示意图,图5是图4所示柔性电路板1沿B-B处剖开的截面结构示意图,图6是图4所示柔性电路板1的部分结构示意图。
一些实施例中,柔性电路板1具有弯折部1a和连接弯折部1a的焊接部1b。柔性电路板1可以为一体成型的结构件,弯折部1a和焊接部1b为柔性电路板1的两个部分。弯折部1a能够发生弯折等变形,使得柔性电路板1能够形变。柔性电路板1可以通过焊接部1b焊接其他部件(例如印制电路板),也即,焊接部1b用于连接其他部件,以实现与其他部件的电连接。其中,焊接部1b的数量可以为两个,两个焊接部1b可以分别连接于弯折部1a的两端,两个焊接部1b可以分别焊接至不同的部件,柔性电路板1能够实现不同部件之间的电连接。
柔性电路板1包括多个导电层11和多个绝缘层12,多个导电层11和多个绝缘层12堆叠设置,相邻的两层导电层11之间均设有绝缘层12。导电层11用于实现导电作用,导电层11可以采用铜箔等导电材料。绝缘层12用于实现绝缘作用,绝缘层12可以采用聚酰亚胺(Polyimide,PI)等绝缘材料。绝缘层12能够对相邻的导电层11进行电隔离。
可以理解的是,导电层11与绝缘层12之间可以设置粘接层(附图未示出)以实现彼此固定,也可以不设置粘接层、直接相互接触并固定;处于不同位置的导电层11与相邻的绝缘层12之间是否设置粘接层的情况可以相同或不同。本申请实施例对多个导电层11与多个绝缘层12的固定方式、固定结构不作严格限定。
示例性的,多个导电层11包括第一焊接层111、第二焊接层112及走线层113。
其中,第一焊接层111和第二焊接层112均为导电层,第一焊接层111和第二焊接层112用于焊接其他部件,以实现柔性电路板1与其他部件之间的电连接。其中,第一焊接层111和第二焊接层112均位于焊接部1b。第一焊接层111为焊接部1b的其中一个表层,第一焊接层111由多个彼此间隔设置的第一焊盘1111组成。在本申请实施例中,两个结构彼此间隔设置是指这两个结构分隔开一定距离,两者之间形成间隙。多个第一焊盘1111可以呈阵列排布或者呈其他排布方式。第二焊接层112为焊接部1b的另一个表层,第二焊接层112由多个彼此间隔设置的第二焊盘1121组成。多个第二焊盘1121可以呈阵列排布或者呈其他排布方式。在本申请实施例中,焊接部1b的表层是指焊接部1b的最外侧的层结构,柔性电路板1的“外侧”是指靠近外部空间的方位。
其中,走线层113为导电层,走线层113中至少布设有走线,以通过走线实现电信号传输。其中,电信号可以包括但不限于电源信号、地及数据信号中的一者或多者。走线层113位于第一焊接层111与第二焊接层112之间,且自焊接部1b延伸至弯折部1a。走线层113的数量可以为一层或多层,走线层113的数量为多层时,相邻的两层走线层113之间均设有绝缘层。
其中,第一焊盘1111和第二焊盘1121通过通孔导体13相连,通孔导体13连接走线层113。此时,第一焊盘1111和第二焊盘1121能够通过通孔导体13实现两者之间的电连接,同时,还可以通过通孔导体13电连接走线层113。
示例性的,第一焊盘1111和第二焊盘1121的数量可以相同,多个第一焊盘1111和多个第二焊盘1121可以一一对应设置,对应的第一焊盘1111和第二焊盘1121通过通孔导体13相连。对应的第一焊盘1111和第二焊盘1121的形状及尺寸可以相同或相近。通孔导体13可以为形成于通孔孔壁的导电层结构,或者填充于通孔中的导体柱结构,本申请实施例对此不作严格限定。
在其他一些实施例中,第一焊盘1111和第二焊盘1121的数量也可以不相同,部分第一焊盘1111和部分第二焊盘1121对应设置,或者,部分第一焊盘1111和全部第二焊盘1121对应设置,或者全部第一焊盘1111和部分第二焊盘1121对应设置。对应的第一焊盘1111和第二焊盘1121仍可以通过通孔导体13相连。
示例性的,多个绝缘层12包括第一绝缘层121和第二绝缘层122。第一绝缘层121位于第一焊接层111与相邻的走线层113之间,且自焊接部1b延伸至弯折部1a。第一绝缘层121在焊接部1b的部分隔离第一焊接层111与相邻走线层113。第一绝缘层121位于弯折部1a的部分形成弯折部1a的一个表层,形成保护层,用于保护弯折部1a的内部结构。
第二绝缘层122位于第二焊接层112与相邻的走线层113之间,且自焊接部1b延伸至弯折部1a。第二绝缘层122在焊接部1b的部分隔离第二焊接层112与相邻走线层113。第二绝缘层122位于弯折部1a的部分形成弯折部1a的另一个表层,形成保护层,用于保护弯折部1a的内部结构。
请结合参阅图5至图7,图7是图5所示走线层113的部分结构示意图。
一些实施例中,走线层113包括导体块1131和走线1132,导体块1131位于焊接部1b,走线1132的一端连接导体块1131,另一端延伸至弯折部1a。第一焊盘1111和第二焊盘1121通过通孔导体13连接导体块1131,第一焊盘1111和第二焊盘1121可以经导体块1131及走线1132电连接至柔性电路板1的其他部分或者其他部件。
在本实施例中,由于第一焊接层111和第二焊接层112作为焊接部1b的两个表层,第一焊接层111只排布第一焊盘1111、不排布走线,第二焊接层112只排布第二焊盘1121、不排布走线,因此焊接部1b无需在第一焊接层111和第二焊接层112的外侧排布保护层(或称为阻焊层),也就无需设置阻焊开窗结构,从而可以实现去阻焊设计,焊接部1b的焊盘间距(也即相邻两个的第一焊盘1111的间距、相邻两个第二焊盘1121的间距)不受走线和阻焊开窗结构的限制,焊盘间距相较于现有技术明显降低,从而减小焊接部1b的板面面积,有利于柔性电路板1的小型化。此外,柔性电路板1的走线排布于走线层113,为柔性电路板1的内层结构,被绝缘层12或保护层覆盖,有利于提升柔性电路板1的线路可靠性。
此外,本申请柔性电路板1相较于传统产品,将多个焊盘单独设于焊接层,虽然焊接层的设置可能导致了导电层数量的增加(例如图5所示实施例相较于图2所示结构增加了一层导电层),但由于导电层11的厚度很小,例如目前的铜箔层通常为0.25微米的厚度,因此本申请柔性电路板1的整体厚度的增加量小、可控,不会对应用该柔性电路板1的电路板组件及电子设备的小型化造成明显的不良影响或者障碍。
其中,导体块1131和走线1132均为导电件,导体块1131用于通过通孔导体13电连接第一焊盘1111及第二焊盘1121,还可以用于电连接柔性电路板1的内层导电结构(例如走线1132),使得柔性电路板1能够通过第一焊盘1111及第二焊盘1121实现与其他部件的电连接。
一些实施例中,导体块1131的形状可以与第一焊盘1111形状相同或相近,例如都为圆形。示例性的,导体块1131的面积与第一焊盘1111的面积相同。其中,如图5所示,相邻两个第一焊盘1111的中心间距包括:两个第一焊盘1111的半径R、走线1132宽度W、以及两个第一焊盘1111与走线1132的间距S3、S4,也即相邻两个第一焊盘1111的中心间距=2R+W+S3+S4。例如,一些产品中,在相同的加工能力下,以最小值为例,R为0.15mm,S为0.075mm,S3、S4为0.075mm,W为0.1mm,则焊接部1b的焊盘间距降低至0.55mm,本申请焊盘间距相较于传统方案可以减小约22%,在多个焊盘阵列排布的结构下,本申请柔性电路板1相较于传统产品,其焊接部1b的板面面积可以减小约40%,焊接部1b的板面面积大幅度减小,有利于柔性电路板1的小型化,有助于应用该柔性电路板1的电路板组件及电子设备的小型化。
请参阅图8,图8是本申请实施例提供的柔性电路板1在另一些实施例中的内部结构示意图。本实施例所示柔性电路板1可以包括前文实施例中的大部分技术特征,以下主要说明两者的区别,两者相同的部分不再赘述。
一些实施例中,导体块1131的面积可以小于第一焊盘1111的面积。在本实施例中,由于第一焊盘1111和第二焊盘1121通过通孔导体13连接导体块1131,第一焊盘1111和第二焊盘1121的位置受限于导体块
1131的设置,通过使导体块1131的面积小于第一焊盘1111的面积,使得导体块1131的面积满足内部连接需求(也即与通孔导体13连接)的情况下,可以设置为较小值,从而在走线层113满足走线1132排布需求的情况下,相邻的两个导体块1131的间距可以较小,使得相邻两个第一焊盘1111的中心间距较小,从而能够进一步减小焊接部1b的焊盘间距,有利于柔性电路板1的小型化。
请结合参阅图9和图10,图9是本申请实施例提供的柔性电路板1在另一些实施例中的内部结构示意图,图10是图9所示柔性电路板1的部分结构示意图。本实施例所示柔性电路板1可以包括前文实施例中的大部分技术特征,以下主要说明两者的区别,两者相同的部分不再赘述。
一些实施例中,柔性电路板1的走线层113的数量可以为多层,例如两层、三层、四层等,本实施例以两层为例进行说明和示意。其中,多个第一焊盘1111连接的多个导体块1131可以分散排布,位于不同的走线层113中。例如,多个第一焊盘1111中的至少两个第一焊盘1111对应连接的导体块1131可以位于不同的走线层113。例如,多个第一焊盘1111中包括第一个第一焊盘和第二个第一焊盘,第一个第一焊盘连接第一个导体块,第一个导体块位于第一个走线层,第二个第一焊盘连接第二个导体块,第二个导体块位于第二个走线层。上述“第一个”和“第二个”是为了区别两个结构而进行的描述,并不构成顺序限定、重要性限定或其他限定。
可以理解的,由于排布有导体块1131的走线层113,均还需排布与导体块1131连接的走线1132,当与多个第一焊盘1111连接的多个导体块1131集中排布于柔性电路板1的某一层走线层113时,会导致该层走线层113有较高的走线排布需求,继而导致该层走线层113的空间紧张、走线排布困难。而当多个第一焊盘1111中的至少两个第一焊盘1111对应连接的导体块1131位于不同的走线层113时,与导体块1131连接的走线1132同样可以分散排布于不同的走线层113,从而降低了走线层113的布线难度,提高了布线灵活度。
一些实施例中,柔性电路板1的焊接部1b设有多个打孔区域,多个通孔导体13一一对应地穿过多个打孔区域。其中,第一焊接层111、第二焊接层112及走线层113均设有对应的多个打孔区域。上述打孔区域既包括通孔导体13占用的空间,还包括位于通孔导体13周围一定范围内的空间。例如,第一焊接层111的多个打孔区域设有多个第一焊盘1111,多个通孔导体13穿过多个第一焊盘1111且连接第一焊盘1111。第二焊接层112的多个打孔区域设有多个第二焊盘1121,多个通孔导体13穿过多个第二焊盘1121且连接第二焊盘1121。
走线层113的数量可以为一层或多层,每层走线层113均设有多个打孔区域,各打孔区域均设有支撑块,多个通孔导体13一一对应地穿过多个打孔区域,通孔导体13穿过支撑块且连接支撑块。示例性的,如图5所示,当走线层113的数量为一层时,多个第一焊盘1111连接的多个导体块1131都位于该层走线层113时,位于走线层113的各打孔区域的支撑块为导体块1131,通孔导体13穿过导体块1131且与导体块1131连接。如图9所示,当走线层113的数量为多层,多个第一焊盘1111连接的多个导体块1131分布于不同的走线层113时,位于各层走线层113的多个打孔区域的支撑块可以为导体块1131或底垫1133(target pad)。也即,当走线层113为多层时,走线层113中的打孔区域若没有排布导体块1131,则排布底垫1133。其中,底垫1133与导体块1131本质上都为导体结构,两者的区别在于底垫1133不连接走线,在柔性电路板1的传输电路中为悬空结构,而导体块1131连接走线1132,为传输电路的一部分。其中,底垫1133的面积可以大于、小于或等于导体块1131的面积,本申请实施例对此不作严格限定。
在本实施例中,由于柔性电路板1的每层走线层113的打孔区域均设有支撑块(导体块1131或底垫1133),使得柔性电路板1的各打孔区域的整体支撑结构稳定、不易发生坍塌,并且柔性电路板1的多个打孔区域厚度能够保持一致,有利于批量打孔和填充金属,提高了柔性电路板1的生产效率和良率。
可以理解的是,在前述实施例中,当柔性电路板1的走线层113的数量较少时(例如一层、两层或三层),柔性电路板1的弯折部1a的厚度很小,能够保证弯折性能,使得柔性电路板1能够满足多样化的安装环境,并且可靠性较佳。在其他一些实施例中,柔性电路板1的走线层113的数量也可以较多,以满足多传输通道等布线需求。
请参阅图11,图11是本申请实施例提供的柔性电路板1在另一些实施例中的内部结构示意图。本实施例所示柔性电路板1可以包括前文实施例中的大部分技术特征,以下主要说明两者的区别,两者相同的部分不再赘述。
一些实施例中,多个导电层11还包括第一布线层114和第二布线层115,第一布线层114和第二布线层115均位于弯折部1a。第一布线层114与第一焊接层111同层设置。第一布线层114为导电层,至少布设有一根或多根走线,以通过走线实现电信号传输。第二布线层115与第二焊接层112同
层设置。第二布线层115为导电层,至少布设有一根或多根走线,以通过走线实现电信号传输。其中,第一布线层114和/或第二布线层115可以电连接走线层113。
柔性电路板1还包括第一保护层141和第二保护层142,第一保护层141和第二保护层142均位于弯折部1a,第一保护层141位于第一布线层114背向走线层113的一侧,第二保护层142位于第二布线层115背向走线层113的一侧,第一保护层141和第二保护层142分别为弯折部1a的两个表层。第一保护层141和第二保护层142均为绝缘层,用于保护柔性电路板1的内部结构,第一保护层141和第二保护层142也可以称为阻焊层。
在本实施例中,由于柔性电路板1的弯折部1a设有第一布线层114和第二布线层115,第一布线层114和第二布线层115及走线层113均可以用于排布走线,因此柔性电路板1可以更好地满足多传输通道等布线需求。
请参阅图12,图12是本申请实施例提供的柔性电路板1在另一些实施例中的内部结构示意图。本实施例所示柔性电路板1可以包括前文实施例中的大部分技术特征,以下主要说明两者的区别,两者相同的部分不再赘述。
一些实施例中,当柔性电路板1的导电层11的数量等于或大于两层时,柔性电路板1的至少一个绝缘层12可以在弯折部1a形成空气间隙(Airgap),也即柔性电路板1的弯折部1a形成一个或多个空气间隙,使得柔性电路板1位于空气间隙两侧的结构可以相对独立地活动,以提升柔性电路板1的弯折部1a的弯折性能。
例如,柔性电路板1可以为四层板结构,柔性电路板1的多个导电层11可以包括第一布线层114、第二布线层115及两层走线层113,位于两个走线层113之间的绝缘层12可以在弯折部1a形成空气间隙121。其中,位于两个走线层113之间的绝缘层12可以包括第一子绝缘层122和第二子绝缘层123,第一子绝缘层122在焊接部1b的部分和第二子绝缘层123在焊接部1b的部分可以通过其上的背胶压合固定,第一子绝缘层122在弯折部1a的部分和第二子绝缘层123在弯折部1a的部分上的背胶可以去除或省略,第一子绝缘层122在弯折部1a的部分与第二子绝缘层123在弯折部1a的部分之间形成空气间隙121。
在其他一些实施例中,柔性电路板1的多层导电层11不包括第一布线层114和第二布线层115,而包括多层走线层113时,同样可以通过在弯折部1a形成一个或多个空气间隙,使得柔性电路板1的弯折部1a的弯折性能较佳。
可以理解的是,柔性电路板1的导电层11的数量等于或大于两层时,柔性电路板1的叠层结构可以有多种实现方式。例如,当导电层11的数量为三层时,弯折部1a可以通过一个空气间隙形成单层+双层的叠层结构,或者通过两个空气间隙形成单层+单层+单层的叠层结构。当导电层11的数量为四层时,弯折部1a可以通过一个空气间隙形成双层+双层的叠层结构,或者通过两个空气间隙形成单层+双层+单层的叠层结构,或者通过三个空气间隙形成单层+单层+单层+单层的叠层结构。本申请实施例对柔性电路板1的导电层11的数量及具体叠层结构不作严格限定。
请参阅图13,图13是本申请实施例提供的柔性电路板1在另一些实施例中的内部结构示意图。
一些实施例中,柔性电路板1具有弯折部1a和连接弯折部1a的焊接部1b,柔性电路板1可以为一体成型的结构件,弯折部1a和焊接部1b为柔性电路板1的两个部分。弯折部1a能够发生弯折等变形,使得柔性电路板1能够形变。柔性电路板1可以通过焊接部1b焊接其他部件(例如印制电路板),也即,焊接部1b用于连接其他部件,以实现与其他部件的电连接。其中,焊接部1b的数量可以为两个,两个焊接部1b可以分别连接于弯折部1a的两端,两个焊接部1b可以分别焊接至不同的部件,柔性电路板1能够实现不同部件之间的电连接。
在前文实施例中,柔性电路板1的焊接部1b的两侧表层均形成焊接结构,在本实施例中,柔性电路板1的焊接部1b的一侧表层形成焊接结构,另一侧不形成焊接结构。具体的:
柔性电路板1包括多个导电层15、多个绝缘层16以及第一保护层171,多个导电层15、多个绝缘层16以及第一保护层171堆叠设置,相邻的两层导电层15之间均设有绝缘层16。导电层15用于实现导电作用,导电层15可以采用铜箔等导电材料。绝缘层16用于实现绝缘作用,绝缘层16可以采用聚酰亚胺(Polyimide,PI)等绝缘材料。绝缘层16能够对相邻的导电层15进行电隔离。
可以理解的是,导电层15与绝缘层16之间可以设置粘接层(附图未示出)以实现彼此固定,也可以不设置粘接层、直接相互接触并固定;处于不同位置的导电层15与相邻的绝缘层16之间是否设置粘接层的情况可以相同或不同。本申请实施例对多个导电层15与多个绝缘层16的固定方式、固定结构不作严格
限定。
示例性的,多个导电层15包括焊接层151和走线层152。
其中,焊接层151为导电层,焊接层151用于焊接其他部件,以实现柔性电路板1与其他部件之间的电连接。焊接层151位于焊接部1b,焊接层151为焊接部1b的其中一个表层。焊接层151由多个彼此间隔设置的焊盘1511组成。多个焊盘1511可以呈阵列排布或者呈其他排布方式。
其中,走线层152为导电层,走线层152中至少布设有走线,以通过走线实现电信号传输。其中,电信号可以包括但不限于电源信号、地及数据信号中的一者或多者。走线层152位于焊接层151的一侧,且自焊接部1b延伸至弯折部1a。走线层152的数量可以为一层或多层,走线层152的数量为多层时,相邻的两层走线层152之间均设有绝缘层。焊盘1511通过通孔导体18连接走线层152。通孔导体18可以为形成于通孔孔壁的导电层结构,或者填充于通孔中的导体柱结构,本申请实施例对此不作严格限定。
其中,走线层152可以包括导体块1521和走线1522,导体块1521位于焊接部1b,走线1522的一端连接导体块1521,另一端延伸至弯折部1a。焊接层151的焊盘1511通过通孔导体18连接导体块1521,焊盘1511可以经导体块1521及走线1522电连接至柔性电路板1的其他部分或者其他部件。
第一保护层171位于走线层152背向焊接层151的一侧,第一保护层171自焊接部1b延伸至弯折部1a,第一保护层171位于焊接部1b的部分形成焊接部1b的另一个表层,位于弯折部1a的部分形成弯折部1a的其中一个表层。第一保护层171也为绝缘层,也可以称为阻焊层,用于保护柔性电路板1的内部结构。焊接部1b于第一保护层171一侧不设置焊接结构,第一保护层171在焊接部1b处无需设置阻焊开窗等结构,可以为连续的、完整的面结构。
其中,多个绝缘层16可以包括第一绝缘层161,第一绝缘层161位于焊接层151与相邻的走线层152之间,且自焊接部1b延伸至弯折部1a,第一绝缘层161位于弯折部1a的部分形成弯折部1a的另一个表层。第一绝缘层161位于焊接部1b的部分用于隔离焊接层151与走线层152。
在本实施例中,由于焊接层151作为焊接部1b的其中一个表层,焊接层151只排布焊盘1511、不排布走线,因此焊接部1b无需在焊接层151的外侧排布保护层(或称为阻焊层),也就无需设置阻焊开窗结构,从而可以实现去阻焊设计,焊接部1b的焊盘间距不受走线和阻焊开窗结构的限制,焊盘间距相较于现有技术明显降低,从而减小焊接部1b的板面面积,有利于柔性电路板1的小型化。
此外,本申请柔性电路板1相较于传统产品,将多个焊盘单独设于焊接层,虽然焊接层的设置可能导致了导电层数量的增加,但由于导电层的厚度很小,例如目前的铜箔层通常为0.25微米的厚度,因此本申请柔性电路板1的整体厚度的增加量小、可控,不会对应用该柔性电路板1的电路板组件及电子设备的小型化造成明显的不良影响或者障碍。
一些实施例中,导体块1521的形状可以与焊盘1511形状相同或相近,例如都为圆形。示例性的,导体块1521的面积与焊盘1511的面积相同。其中,如图13所示,相邻两个焊盘1511的中心间距包括:两个焊盘1511的半径R、走线宽度W、以及两个焊盘1511与走线的间距S3、S4,也即相邻两个焊盘1511的中心间距=2R+W+S3+S4。例如,一些产品中,在相同的加工能力下,以最小值为例,R为0.15mm,S为0.075mm,S3、S4为0.075mm,W为0.1mm,则焊盘间距降低至0.55mm,本申请焊盘间距相较于传统方案可以减小约22%,在多个焊盘1511阵列排布的结构下,本申请柔性电路板1相较于传统产品,其焊接部1b的板面面积可以减小约40%,焊接部1b的板面面积大幅度减小,有利于柔性电路板1的小型化,有助于应用该柔性电路板1的电路板组件及电子设备的小型化。
在其他一些实施例中,导体块1521的面积可以小于焊盘1511的面积。在本实施例中,由于焊盘1511通过通孔导体18连接导体块1521,焊盘1511的位置受限于导体块1521的设置,通过使导体块1521的面积小于焊盘1511的面积,使得导体块1521的面积满足内部连接需求(也即与通孔导体18连接)的情况下,可以设置为较小值,从而在走线层152满足走线排布的情况下,相邻的两个导体块1521的间距可以较小,使得相邻两个焊盘1511的中心间距较小,从而能够进一步减小焊接部1b的焊盘间距,有利于柔性电路板1的小型化。
请参阅图14,图14是本申请实施例提供的柔性电路板1在另一些实施例中的内部结构示意图。本实施例所示柔性电路板1可以包括前文实施例中的大部分技术特征,以下主要说明两者的区别,两者相同的部分不再赘述。
一些实施例中,柔性电路板1的走线层152的数量可以为多层,例如两层、三层、四层等,本实施例以两层为例进行说明和示意。其中,相邻的两个焊盘1511对应连接的两个导体块1521可以位于不同的走线层152。其中,多个焊盘1511连接的多个导体块1521可以分散排布,位于不同的走线层152中。例如,
多个焊盘1511中的至少两个焊盘1511对应连接的导体块1521可以位于不同的走线层152。例如,多个焊盘1511中包括第一个焊盘和第二个焊盘,第一个焊盘连接第一个导体块,第一个导体块位于第一个走线层,第二个焊盘连接第二个导体块,第二个导体块位于第二个走线层。上述“第一个”和“第二个”是为了区别两个结构而进行的描述,并不构成顺序限定、重要性限定或其他限定。
可以理解的,由于排布有导体块1521的走线层152,均还需排布与导体块1521连接的走线1522,当与多个焊盘1511连接的多个导体块1521集中排布于柔性电路板1的某一层走线层152时,会导致该层走线层152有较高的走线排布需求,继而导致该层走线层152的空间紧张、走线排布困难。而当多个焊盘1511中的至少两个焊盘1511对应连接的导体块1521位于不同的走线层152时,与导体块1521连接的走线1522同样可以分散排布于不同的走线层152,从而降低了走线层152的布线难度,提高了布线灵活度。
一些实施例中,柔性电路板1的焊接部1b设有多个打孔区域,多个通孔导体18一一对应地穿过多个打孔区域。其中,焊接层151和走线层152均设有对应的多个打孔区域。上述打孔区域既包括通孔导体18占用的空间,还包括位于通孔导体18周围一定范围内的空间。例如,焊接层151的多个打孔区域设有多个焊盘1511,多个通孔导体18穿过多个焊盘1511且连接焊盘1511。
走线层152的数量可以为一层或多层,每层走线层152均设有多个打孔区域,各打孔区域均设有支撑块,多个通孔导体18一一对应地穿过多个打孔区域,通孔导体18穿过支撑块且连接支撑块。示例性的,如图13所示,当走线层152的数量为一层时,多个焊盘1511连接的多个导体块1521都位于该层走线层152时,位于走线层152的各打孔区域的支撑块为导体块1521,通孔导体18穿过导体块1521且与导体块1521连接。如图14所示,当走线层152的数量为多层,多个焊盘1511连接的多个导体块1521分布于不同的走线层152时,位于各层走线层152的多个打孔区域的支撑块可以为导体块1521或底垫1523(target pad)。也即,当走线层152为多层时,走线层152中的打孔区域若没有排布导体块1521,则排布底垫1523。其中,底垫1523与导体块1521本质上都为导体结构,两者的区别在于底垫1523不连接走线,在柔性电路板1的传输电路中为悬空结构,而导体块1521连接走线1522,为传输电路的一部分。其中,底垫1523的面积可以大于、小于或等于导体块1521的面积,本申请实施例对此不作严格限定。
在本实施例中,由于柔性电路板1的每层走线层152的打孔区域均设有支撑块(导体块1521或底垫1523),使得柔性电路板1的各打孔区域的整体支撑结构稳定、不易发生坍塌,并且柔性电路板1的多个打孔区域厚度能够保持一致,有利于批量打孔和填充金属,提高了柔性电路板1的生产效率和良率。
可以理解的是,当走线层152的数量为多层时,多个通孔导体18中的部分通孔导体18可以不穿过所有的走线层152,而是穿过部分走线层152。例如,如图14所示,走线层152的数量为两层,部分通孔导体18穿过两层走线层152,部分通孔导体18穿过一层走线层152。在这种情况下,不同走线层152的打孔区域的数量可以不同,则排布于打孔区域的支撑块的数量可以不同。对于未穿过所有走线层152的通孔导体18,这部分未被通孔导体18穿过的走线层152可以具有支撑区域,支撑区域对应其他被通孔导体18穿过的走线层152的打孔区域设置,支撑区域同样可以设置有支撑块,以提高柔性电路板1对应于该通孔导体18的区域的支撑强度。
可以理解的是,在前述实施例中,当柔性电路板1的走线层152的数量较少时(例如一层、两层或三层),柔性电路板1的弯折部1a的厚度很小,能够保证弯折性能,使得柔性电路板1能够满足多样化的安装环境,并且可靠性较佳。在其他一些实施例中,柔性电路板1的走线层152的数量也可以较多,以满足多传输通道等布线需求。
请参阅图15,图15是本申请实施例提供的柔性电路板1在另一些实施例中的内部结构示意图。本实施例所示柔性电路板1可以包括前文实施例中的大部分技术特征,以下主要说明两者的区别,两者相同的部分不再赘述。
一些实施例中,多个导电层15还包括布线层153,布线层153位于弯折部1a,布线层153与焊接层151同层设置。布线层153为导电层,至少布设有一根或多根走线,以通过走线实现电信号传输。布线层153采用铜箔等导电材料。布线层153可以电连接走线层152。
柔性电路板1还包括第二保护层172,第二保护层172位于布线层153背向走线层152的一侧,第二保护层172位于弯折部1a,为弯折部1a的另一个表层。第二保护层172为绝缘层,用于保护柔性电路板1的内部结构,也可以称为阻焊层。
在本实施例中,由于柔性电路板1的弯折部1a设有布线层153,布线层153和走线层152均可以用于排布走线,因此柔性电路板1可以更好地满足多传输通道等布线需求。
请参阅图16,图16是本申请实施例提供的柔性电路板1在另一些实施例中的内部结构示意图。本实
施例所示柔性电路板1可以包括前文实施例中的大部分技术特征,以下主要说明两者的区别,两者相同的部分不再赘述。
一些实施例中,当柔性电路板1的导电层15的数量等于或大于两层时,柔性电路板1的至少一个绝缘层16可以在弯折部1a形成空气间隙(Airgap),也即柔性电路板1的弯折部1a形成一个或多个空气间隙,使得柔性电路板1位于空气间隙两侧的结构可以相对独立地活动,以提升柔性电路板1的弯折部1a的弯折性能。
例如,柔性电路板1可以为三层板结构,柔性电路板1的多个导电层15可以包括布线层153及两层走线层152,位于两个走线层152之间的绝缘层16可以在弯折部1a形成空气间隙161。其中,位于两个走线层152之间的绝缘层16可以包括第一子绝缘层162和第二子绝缘层163,第一子绝缘层162在焊接部1b的部分和第二子绝缘层163在焊接部1b的部分可以通过其上的背胶压合固定,第一子绝缘层162在弯折部1a的部分和第二子绝缘层163在弯折部1a的部分上的背胶可以去除或省略,第一子绝缘层162在弯折部1a的部分与第二子绝缘层163在弯折部1a的部分之间形成空气间隙161。其中,空气间隙也可以形成在布线层153与走线层152之间。
在其他一些实施例中,柔性电路板1的多层导电层15不包括布线层153,而包括多层走线层152时,同样可以通过在弯折部1a形成一个或多个空气间隙,使得柔性电路板1的弯折部1a的弯折性能较佳。
可以理解的是,柔性电路板1的导电层15的数量等于或大于两层时,柔性电路板1的叠层结构可以有多种实现方式。例如,当导电层15的数量为三层时,弯折部1a可以通过一个空气间隙形成单层+双层的叠层结构,或者通过两个空气间隙形成单层+单层+单层的叠层结构。当导电层15的数量为四层时,弯折部1a可以通过一个空气间隙形成双层+双层的叠层结构,或者通过两个空气间隙形成单层+双层+单层的叠层结构,或者通过三个空气间隙形成单层+单层+单层+单层的叠层结构。本申请实施例对柔性电路板1的导电层15的数量及具体叠层结构不作严格限定。
在其他一些实施例中,柔性电路板1也可以包括两个布线层153,例如包括第一布线层和第二布线层,第一布线层和第二布线层均位于弯折部1a,第一布线层与焊接层151同层设置,第二布线层位于第一保护层171背向走线层152的一侧。此时,柔性电路板1还可以包括第二保护层和第三保护层,第二保护层和第三保护层均位于弯折部1a,第二保护层位于第一布线层背向走线层152的一侧,第三保护层位于第二布线层背向走线层152的一侧。本实施例中,第一保护层171位于弯折部1a的部分不再为弯折部1a的表层,而是为弯折部1a的内部层结构。
在上述多个实施例中,柔性电路板1可以包括两个焊接部1b和弯折部1a,弯折部1a连接在两个焊接部1b之间,两个焊接部1b焊接不同的部件,柔性电路板1实现不同部件之间的电连接。
在其他一些实施例中,柔性电路板1也可以是包括焊接部1b、弯折部1a,还可以包括连接部,弯折部1a可以连接在焊接部1b与连接部之间,连接部可以用于固定电连接器,电连接器包括但不限于板对板连接器(board to board,BTB)等。当焊接部1b和电连接器连接至不同的部件时,柔性电路板1能够实现不同部件之间的电连接。其中,柔性电路板1的焊接部1b及弯折部1a的设计可以与前文多个实施例相同或相似,此处不再赘述。
在其他一些实施例中,柔性电路板1也可以是包括焊接部1b、弯折部1a及贴装部,弯折部1a可以连接在焊接部1b与贴装部之间,贴装部可以用于贴装元器件,元器件可以是芯片和/或芯片的附属器件等。当柔性电路板1的焊接部1b固定且电连接至其他部件时,贴装于柔性电路板1的贴装部的元器件电连接至对应部件。其中,当柔性电路板1的贴装部贴装元器件时,柔性电路板1与元器件共同形成柔性电路板1组件(Flexible Printed Circuit Assemble,FPCA)。其中,柔性电路板1的焊接部1b及弯折部1a的设计可以与前文多个实施例相同或相似,此处不再赘述。
请结合参阅图17至图19,图17是本申请实施例提供的电路板组件10在一些实施例中的结构示意图,图18是图17所示电路板组件10在另一角度的结构示意图,图19是图17所示电路板组件10的部分结构的截面示意图。
一些实施例中,电路板组件10包括电路板2和柔性电路板1,柔性电路板1的焊接部1b焊接电路板2,弯折部1a可以依据安装环境发生变形。其中,电路板2可以为印制电路板或者柔性电路板。电路板2上设有多个焊盘21,电路板2的多个焊盘21与柔性电路板1的焊接部1b的焊盘结构(也即第一焊盘1111、第二焊盘1121)相对应。
其中,焊接部1b可以通过表面贴装技术(Surface mount technology,SMT)、热压焊(Hotbar)工艺或其他方式固定且电连接至电路板2。可以理解的是,图19中以图9所示柔性电路板1的结构进行示意,本实施例电路板组件10的柔性电路板1也可以采用前文实施例中的焊接部1b的两个表层均具有焊接结构的其他柔性电路板结构,例如图5、图8、图11或图12所示结构。
其中,柔性电路板1的焊接部1b通过热压焊固定至电路板2时,可以预先分别在焊接部1b的焊盘(也即第一焊盘1111、第二焊盘1121)上和电路板2的焊盘21上预置锡膏和助焊剂,再通过脉冲热压头加热来实现焊盘之间的焊接,从而实现柔性电路板1和电路板2的电气导通。柔性电路板1的焊接部1b通过表面贴装技术固定至电路板2时,可以将柔性电路板1当作元器件焊接至电路板2,或是将电路板2当作元器件焊接至柔性电路板1,从而实现柔性电路板1和电路板2的电气导通。
在本实施例中,由于柔性电路板1的焊接部1b的焊盘(也即第一焊盘1111、第二焊盘1121)为凸出表面的结构,能够在焊接过程中避免锡膏坍塌短路,保证焊点具有一定高度,从而改善焊接质量和可靠性。
请结合参阅图20和图21,图20是本申请实施例提供的电路板组件10在另一些实施例中的结构示意图,图21是图20所示电路板组件10的部分结构示意图。
一些实施例中,电路板组件10包括电路板2和柔性电路板1,柔性电路板1的焊接部1b焊接电路板2,弯折部1a可以依据安装环境发生变形。其中,电路板2可以为印制电路板或者柔性电路板。电路板2上设有多个焊盘21,电路板2的多个焊盘21与柔性电路板1的焊接部1b的焊盘1511结构相对应。
其中,焊接部1b可以通过表面贴装技术(Surface mount technology,SMT)或其他方式固定且电连接至电路板2。可以理解的是,图21中以图14所示柔性电路板1的结构进行示意,本实施例电路板组件10的柔性电路板1也可以采用前文实施例中的焊接部1b的其中一个表层具有焊接结构、另一个表层不设置焊接结构的其他柔性电路板结构,例如图13、图15或图16所示结构。
其中,柔性电路板1的焊接部1b通过表面贴装技术固定至电路板2时,可以将柔性电路板1当作元器件焊接至电路板2,或是将电路板2当作元器件焊接至柔性电路板1,从而实现柔性电路板1和电路板2的电气导通。
一些实施例中,在图17至图21所示电路板组件10中,电路板组件10还可以包括一个或多个元器件,一个或多个元器件可以焊接于电路板2和/或焊接于柔性电路板1。其中,当电路板2为印制电路板,电路板2上贴装有元器件时,电路板2与元器件可以共同形成印制电路板组件(Printed Circuit Board Assemble,PCBA)。
一些实施例中,在图17至图21所示电路板组件10中,电路板组件10还可以包括电连接器,电连接器可以固定且电连接柔性电路板1,使得柔性电路板1还可以通过电连接器与其他部件电连接。
以下对电路板组件10的一些实施例进行示意性说明。
请参阅图22,图22是本申请实施例提供的电路板组件10在一些实施例中的结构示意图。
一些实施例中,电路板组件10包括第一电路板22、第二电路板23、柔性电路板1、第一元器件31及第二元器件32。柔性电路板1包括两个焊接部1b和连接两个焊接部1b的弯折部1a,柔性电路板1的两个焊接部1b分别焊接第一电路板22和第二电路板23。柔性电路板1的焊接部1b及弯折部1a的结构可以参考前文实施例中的任一种结构。其中,第一电路板22可以为印制电路板或者柔性电路板,第二电路板23可以为印制电路板或者柔性电路板。第一元器件31的数量可以为一个或多个,第一元器件31固定且电连接第一电路板22。第二元器件32的数量可以为一个或多个,第二元器件32固定且电连接第二电路板23。柔性电路板1用于实现第一元器件31与第二元器件32之间的电连接。
其中,第一电路板22和第二电路板23可以堆叠设置,柔性电路板1的弯折部1a发生弯折,使得电路板组件10形成三明治堆叠结构,电路板组件10的整体占用空间较小,所需的安装空间较小,有利于降低安装难度,提高适用范围。在其他一些实施例中,第一电路板22和第二电路板23也可以形成其他相对位置关系,例如错位排布等。
请参阅图23,图23是本申请实施例提供的电路板组件10在另一些实施例中的结构示意图。
一些实施例中,电路板组件10包括第一电路板22、第二电路板23、柔性电路板1、第一电连接器41、第二电连接器42、第一元器件31及第二元器件32。柔性电路板1包括焊接部1b、连接部1c及连接焊接部1b与连接部1c的弯折部1a,柔性电路板1的焊接部1b及弯折部1a的结构可以参考前文实施例中的任一种结构。第一电路板22可以为印制电路板或者柔性电路板。第一元器件31的数量可以为一个或多个,第一元器件31固定且电连接第一电路板22。柔性电路板1的焊接部1b焊
接第一电路板22。第二元器件32的数量可以为一个或多个,第二元器件32固定且电连接第二电路板23。第一电连接器41和第二电连接器42可以分别为公头和母头,公头和母头互相配对。第一电连接器41和第二电连接器42可以为板对板电连接器等。第一电连接器41固定且电连接柔性电路板1的连接部1c,第二电连接器42固定且电连接第二电路板23。第一电连接器41固定且电连接第二电连接器42,柔性电路板1用于实现第一元器件31与第二元器件32之间的电连接。
其中,第一电路板22和第二电路板23可以堆叠设置,柔性电路板1的弯折部1a发生弯折,使得电路板组件10形成三明治堆叠结构,电路板组件10的整体占用空间较小,所需的安装空间较小,有利于降低安装难度,提高适用范围。在其他一些实施例中,第一电路板22和第二电路板23也可以形成其他相对位置关系,例如错位排布等。
请参阅图24,图24是本申请实施例提供的电路板组件10在另一些实施例中的结构示意图。
一些实施例中,电路板组件10包括电路板2、柔性电路板1、第一元器件31及第二元器件32。柔性电路板1包括焊接部1b、贴装部1d及连接焊接部1b与贴装部1d的弯折部1a,柔性电路板1的焊接部1b及弯折部1a的结构可以参考前文实施例中的任一种结构。电路板2可以为印制电路板或者柔性电路板。第一元器件31的数量可以为一个或多个,第一元器件31固定且电连接电路板2。柔性电路板1的焊接部1b焊接电路板2。第二元器件32的数量可以为一个或多个,第二元器件32固定且电连接柔性电路板1的贴装部1d。柔性电路板1用于实现第一元器件31与第二元器件32之间的电连接。
本申请实施例还提供一种电子设备,包括壳体和电路板组件,电路板组件可以采用前述实施例中的任一结构,电路板组件安装于壳体的内部。其中,电子设备可以是但不限于是手机、平板电脑(pad)、便携式游戏机、掌上电脑(personal digital assistant,PDA)、笔记本电脑、超级移动个人计算机(ultra-mobile personal computer,UMPC)、手持计算机、上网本、车载媒体播放设备、可穿戴电子设备、虚拟现实(virtual reality,VR)终端设备、或增强现实(augmented reality,AR)终端设备等电子产品。
示例性的,当电子设备为手机或平板电脑,电路板组件采用图22或图23所示电路板组件10的结构时,第一电路板22和第二电路板23可以分别为主板和副板,第一元器件31可以包括处理器等,第二元器件32可以包括射频芯片等。
示例性的,当电子设备为可穿戴电子设备,例如智能手表或智能手环,电路板组件采用图23所示电路板组件10的结构时,第一电路板22可以为心率模组的电路板,第一元器件31可以包括心率检测传感器等,第二电路板23可以为主板,第二元器件32可以包括处理器等。
示例性的,当电子设备为蓝牙耳机,电路板组件10采用图24所示电路板组件10的结构时,电路板2可以为主板,第一元器件31可以包括处理器等,第二元器件32可以包括麦克风(Microphone,MIC)和/或其附属器件。
可以理解的是,电路板组件的结构是多样化的,电路板组件于不同形态、不同类别、不同尺寸的电子设备中的应用也是多样化的,本申请实施例对此不作严格限定。
以上实施例仅用以说明本申请的技术方案,而非对其限制;尽管参照前述实施例对本申请进行了详细的说明,本领域的普通技术人员应当理解:其依然可以对前述各实施例所记载的技术方案进行修改,或者对其中部分技术特征进行等同替换;而这些修改或者替换,并不使相应技术方案的本质脱离本申请各实施例技术方案的范围。
Claims (18)
- 一种柔性电路板,其特征在于,具有弯折部和连接所述弯折部的焊接部;所述柔性电路板包括多个导电层和多个绝缘层,相邻的两层所述导电层之间均设有所述绝缘层;多个所述导电层包括第一焊接层、第二焊接层及走线层;所述第一焊接层和所述第二焊接层均位于所述焊接部,所述第一焊接层为所述焊接部的其中一个表层,所述第一焊接层由多个彼此间隔设置的第一焊盘组成,所述第二焊接层为所述焊接部的另一个表层,所述第二焊接层由多个彼此间隔设置的第二焊盘组成;所述走线层位于所述第一焊接层与所述第二焊接层之间,且自所述焊接部延伸至所述弯折部,所述第一焊盘和所述第二焊盘通过通孔导体相连,所述通孔导体连接所述走线层。
- 根据权利要求1所述的柔性电路板,其特征在于,所述走线层包括导体块和走线,所述导体块位于所述焊接部,所述走线的一端连接所述导体块,另一端延伸至所述弯折部,所述第一焊盘和所述第二焊盘通过通孔导体连接所述导体块。
- 根据权利要求2所述的柔性电路板,其特征在于,所述导体块的面积小于所述第一焊盘的面积。
- 根据权利要求2或3所述的柔性电路板,其特征在于,所述走线层的数量为多层,多个所述第一焊盘连接的多个所述导体块位于不同的所述走线层。
- 根据权利要求2或3所述的柔性电路板,其特征在于,所述走线层的数量为一层或多层,每层所述走线层均设有多个打孔区域,多个所述通孔导体一一对应地穿过各层所述走线层的多个所述打孔区域;每层所述走线层的多个所述打孔区域均设有支撑块,所述通孔导体穿过所述支撑块且连接所述支撑块;当所述走线层的数量为一层时,所述支撑块为导体块;或者,当所述走线层的数量为多层时,所述支撑块为导体块或底垫。
- 根据权利要求1至5中任一项所述的柔性电路板,其特征在于,多个所述绝缘层包括第一绝缘层和第二绝缘层;所述第一绝缘层位于所述第一焊接层与相邻的所述走线层之间,且自所述焊接部延伸至所述弯折部,所述第一绝缘层位于所述弯折部的部分形成所述弯折部的一个表层;所述第二绝缘层位于所述第二焊接层与相邻的所述走线层之间,且自所述焊接部延伸至所述弯折部,所述第二绝缘层位于所述弯折部的部分形成所述弯折部的另一个表层。
- 根据权利要求1至5中任一项所述的柔性电路板,其特征在于,多个所述导电层还包括第一布线层和第二布线层,所述第一布线层和所述第二布线层均位于所述弯折部,所述第一布线层与所述第一焊接层同层设置,所述第二布线层与所述第二焊接层同层设置;所述柔性电路板还包括第一保护层和第二保护层,所述第一保护层和所述第二保护层均位于所述弯折部,所述第一保护层位于所述第一布线层背向所述走线层的一侧,所述第二保护层位于所述第二布线层背向所述走线层的一侧,所述第一保护层和所述第二保护层分别为所述弯折部的两个表层。
- 根据权利要求7所述的柔性电路板,其特征在于,所述柔性电路板的至少一个所述绝缘层在所述弯折部形成空气间隙。
- 一种柔性电路板,其特征在于,具有弯折部和连接所述弯折部的焊接部;所述柔性电路板包括多个导电层、多个绝缘层以及第一保护层,相邻的两层所述导电层之间均设有所述绝缘层;多个所述导电层包括焊接层和走线层,所述焊接层位于所述焊接部,所述焊接层为所述焊接部的其中一个表层,所述焊接层由多个彼此间隔设置的焊盘组成,所述走线层位于所述焊接层的一侧,且自所述焊接部延伸至所述弯折部,所述焊盘通过通孔导体连接所述走线层;所述第一保护层位于所述走线层背向所述焊接层的一侧,所述第一保护层自所述焊接部延伸至所述弯折部,所述第一保护层位于所述焊接部的部分形成所述焊接部的另一个表层,位于所述弯折部的部分形成所述弯折部的其中一个表层。
- 根据权利要求9所述的柔性电路板,其特征在于,所述走线层包括导体块和走线,所述导体块位于所述焊接部,所述走线的一端连接所述导体块,另一端延伸至所述弯折部,所述焊盘通过通孔导体连接所述导体块。
- 根据权利要求10所述的柔性电路板,其特征在于,所述导体块的面积小于所述焊盘的面积。
- 根据权利要求10或11所述的柔性电路板,其特征在于,所述走线层的数量为多层,多个所述焊盘连接的多个所述导体块位于不同的所述走线层。
- 根据权利要求10或11所述的柔性电路板,其特征在于,所述走线层的数量为一层或多层,每层所述走线层均设有多个打孔区域,多个所述通孔导体一一对应地穿过各层所述走线层的多个所述打孔区域;每层所述走线层的多个所述打孔区域均设有支撑块,所述通孔导体穿过所述支撑块且连接所述支撑块;当所述走线层的数量为一层时,所述支撑块为导体块;或者,当所述走线层的数量为多层时,所述支撑块为导体块或底垫。
- 根据权利要求9至13中任一项所述的柔性电路板,其特征在于,多个所述绝缘层包括第一绝缘层,所述第一绝缘层位于所述焊接层与相邻的所述走线层之间,且自所述焊接部延伸至所述弯折部,所述第一绝缘层位于所述弯折部的部分形成所述弯折部的另一个表层。
- 根据权利要求9至13中任一项所述的柔性电路板,其特征在于,多个所述导电层还包括布线层,所述布线层位于所述弯折部,所述布线层与所述焊接层同层设置;所述柔性电路板还包括第二保护层,所述第二保护层位于所述布线层背向所述走线层的一侧,所述第二保护层位于所述弯折部,为所述弯折部的另一个表层。
- 根据权利要求15所述的柔性电路板,其特征在于,所述柔性电路板的至少一个所述绝缘层在所述弯折部形成空气间隙。
- 一种电路板组件,其特征在于,包括电路板和权利要求1至16中任一项所述的柔性电路板,所述柔性电路板的焊接部焊接所述电路板。
- 一种电子设备,其特征在于,包括壳体及权利要求17所述的电路板组件,所述电路板组件安装于所述壳体的内部。
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CN1806474A (zh) * | 2004-06-11 | 2006-07-19 | 揖斐电株式会社 | 刚挠性电路板及其制造方法 |
CN102164452A (zh) * | 2010-02-23 | 2011-08-24 | 揖斐电株式会社 | 刚挠性电路板及其制造方法 |
US20160095207A1 (en) * | 2014-09-25 | 2016-03-31 | Ibiden Co., Ltd. | Flex-rigid wiring board |
CN105704918A (zh) * | 2016-02-01 | 2016-06-22 | 浪潮(北京)电子信息产业有限公司 | 一种高密度印制电路板 |
CN109819584A (zh) * | 2019-03-07 | 2019-05-28 | 武汉光迅科技股份有限公司 | 一种多层fpc |
CN112672545A (zh) * | 2020-12-01 | 2021-04-16 | 景旺电子科技(珠海)有限公司 | 一种多层电路板的制作方法 |
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CN1806474A (zh) * | 2004-06-11 | 2006-07-19 | 揖斐电株式会社 | 刚挠性电路板及其制造方法 |
CN102164452A (zh) * | 2010-02-23 | 2011-08-24 | 揖斐电株式会社 | 刚挠性电路板及其制造方法 |
US20160095207A1 (en) * | 2014-09-25 | 2016-03-31 | Ibiden Co., Ltd. | Flex-rigid wiring board |
CN105704918A (zh) * | 2016-02-01 | 2016-06-22 | 浪潮(北京)电子信息产业有限公司 | 一种高密度印制电路板 |
CN109819584A (zh) * | 2019-03-07 | 2019-05-28 | 武汉光迅科技股份有限公司 | 一种多层fpc |
CN112672545A (zh) * | 2020-12-01 | 2021-04-16 | 景旺电子科技(珠海)有限公司 | 一种多层电路板的制作方法 |
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