CN106604540A - Circuit board - Google Patents

Abstract

The invention discloses a circuit board. The circuit board includes a circuit board main body, a plurality of welding pads and an insulating layer. The plurality of welding pads and the insulating layer are arranged on the circuit board main body. The welding pads include A first surface and a second surface, the first surface is attached to the main body of the circuit board, the second surface includes a welding area, a first extension area and a second extension area, and the welding area is located on the first Between the extension area and the second extension area, windows are opened in the insulating layer corresponding to the positions of the plurality of pads, so as to expose the welding areas of the second surface of the plurality of pads and the plurality of pads. The insulating layer covers the first extension area and the second extension area. The circuit board can avoid the exposure of the wires connected to the pads and prevent the pads from falling off.

Description

circuit board

technical field

The invention relates to the field of circuit boards, in particular to a circuit board with pads.

Background technique

In various electronic products, such as camera modules, mobile phones, electronic watches, etc., circuit boards are usually used to electrically connect various components of the electronic products, form various driving circuits or connect with external circuits. For example, the surface of the circuit board of the camera module is usually provided with components such as connectors and image sensors, wherein the connectors are electrically connected to the circuit board through Surface Mounted Technology (SMT). Surface mount technology usually requires pads to be set on the circuit board. The number of pads for mounting connectors is usually large, the density is high, and they are arranged in a queue. When mounting, the solder paste should be printed on the pads first. Then align the corresponding part of the connector with the pad to accurately install the connector on the fixed position of the circuit board, and finally melt the solder paste through reflow soldering at high temperature to make the connector and the circuit board The pads on the connector are welded together to realize the electrical connection between the connector and the circuit board. The connector is usually connected to the main board of the mobile phone or other electronic equipment by plugging and unplugging.

Usually, the surface layer of the circuit board is an insulating layer, which plays the role of insulation, solder resistance and protection, and the insulating layer is usually provided with a window, from which the pad is exposed, that is, the pad is not covered by an insulating layer. There are two rows of pads on the part of the circuit board that is connected to the connector, and two through windows are opened on the position of the insulating layer corresponding to the two rows of pads, and the through windows run through between the pads in each row of pads In the prior art, the edge of the window (that is, the edge of the insulating layer) is outside the pad, that is, the window of the insulating layer is larger than the pad, and the insulating layer does not cover the solder pad. There is a gap between the edge of the window and the edge of the pad. In this way, when the connector is plugged into the motherboard of an electronic device such as a mobile phone, the pad is easy to fall off, which affects the connection between the circuit board with the connector and the electronic device such as a mobile phone. The signal transmission of the main board of the device.

Contents of the invention

The technical problem to be solved by the present invention is to provide a circuit board, which can prevent the pads from falling off.

In order to solve the above technical problems, the present invention adopts the following technical solutions:

The present invention provides a circuit board. The circuit board includes a circuit board main body, a plurality of welding pads and an insulating layer. The plurality of welding pads and the insulating layer are arranged on the circuit board main body. The welding pads include The first surface and the second surface are oppositely arranged, the first surface is attached to the circuit board main body, the second surface includes a welding area, a first extension area and a second extension area, and the welding area is located at the Between the first extension area and the second extension area, windows are opened in the insulating layer corresponding to the positions of the plurality of pads, so as to expose the welding areas and the welding areas of the second surface of the plurality of pads. The insulating layer covers the first extension area and the second extension area in gaps between the plurality of welding areas.

Wherein, the first surface is larger than the second surface.

Wherein, the pad includes a third surface and a fourth surface, the third surface and the fourth surface are oppositely arranged, and one end of the third surface is connected to the first extension region, and the other end is connected to the first extension region. One surface, one end of the fourth surface is connected to the second extension region, and the other end is connected to the first surface, and the third surface forms an included angle with the first surface in the range of 45° to 85°, so The fourth surface forms an included angle in the range of 45° to 85° with the first surface.

Wherein, the circuit board further includes a reinforcing layer, and the reinforcing layers are respectively arranged between the insulating layer and the third surface and between the insulating layer and the fourth surface, and are respectively provided to the circuit The board body is extended.

Wherein, the reinforcement layer is a transparent optical adhesive layer.

Wherein, the reinforcement layer is also disposed in the gap between the pads, and the thickness of the reinforcement layer disposed in the gap between the pads is less than or equal to the thickness of the pads.

Wherein, the reinforcement layer extends from the third surface to the first extension area, and the reinforcement layer extends from the fourth surface to the second extension area.

Wherein, the plurality of pads are arranged in a row, and the pads located at both ends of one row have a larger area than other pads.

Wherein, the section of the reinforcing layer perpendicular to the circuit board main body and the third surface is triangular.

Wherein, the main body of the circuit board is a flexible board or a hard board.

Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects: In the circuit board of the present invention, the pad includes a first surface and a second surface, and the first surface is attached to the main body of the circuit board , the second surface includes a welding area, a first extension area, and a second extension area, and an insulating layer covers the first extension area and the second extension area of the pad, increasing the insulation layer to The binding force of the pad prevents the pad from coming off.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a schematic top view of a circuit board in an embodiment of the present invention;

Figure 2a is a partial enlarged view of the circuit board corresponding to part e in Figure 1 in the first embodiment of the present invention;

Fig. 2b is a schematic cross-sectional view of the circuit board along the section line A-A in Fig. 2a in the first embodiment of the present invention;

Fig. 2c is a schematic structural diagram of the pads of the circuit board in the first embodiment of the present invention;

Fig. 2d is a schematic cross-sectional view of the circuit board along the section line B-B in Fig. 2a in the first embodiment of the present invention;

Fig. 3 is a schematic cross-sectional view of the circuit board along the section line B-B in Fig. 2a in the second embodiment of the present invention;

Fig. 4a is a schematic cross-sectional view of the circuit board along the section line A-A in Fig. 2a in the third embodiment of the present invention;

Fig. 4b is a schematic cross-sectional view of the circuit board along the section line B-B in Fig. 2a in the third embodiment of the present invention;

Fig. 5 is a schematic cross-sectional view of the circuit board along the section line B-B in Fig. 2a in the fourth embodiment of the present invention;

Fig. 6a is a partial enlarged view of the circuit board corresponding to part e in Fig. 1 in the fifth embodiment of the present invention;

6b is a schematic cross-sectional view of the circuit board along the section line C-C in FIG. 6a according to the fifth embodiment of the present invention.

detailed description

The technical solutions in the embodiments of the present invention will be clearly described below with reference to the drawings in the embodiments of the present invention. Apparently, the described embodiments are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Please refer to Fig. 1, Fig. 2a, Fig. 2b, Fig. 2c and Fig. 2d, Fig. 1 is a schematic top view of the circuit board in the embodiment of the present invention; Fig. 2a is the part e in Fig. 1 corresponding to the circuit board in the first embodiment of the present invention Figure 2b is a schematic cross-sectional view of the circuit board along the section line A-A in Figure 2a in the first embodiment of the present invention; Figure 2c is a schematic structural view of the pads of the circuit board in the first embodiment of the present invention; Figure 2d is A schematic cross-sectional view of the circuit board along the cutting line B-B in FIG. 2a in the first embodiment of the present invention. In this embodiment, the circuit board includes a circuit board main body 10 , a plurality of pads 20 and an insulating layer 30 . The circuit board body 10 includes a base material and wires (not shown in the figure) disposed on the base material, and the wires include wires (not shown in the figure) connected to the pads 20 . A plurality of pads 20 and the insulating layer 30 are arranged on the circuit board main body 10, the pads 20 include a first surface 21, a second surface 22, a third surface 23 and a fourth surface 24, the first surface 21 is provided opposite to the second surface 22 , and the third surface 23 is provided opposite to the fourth surface 24 . The first surface 21 is attached to the circuit board main body 10, the second surface 22 includes a welding area 221, a first extension area 222 and a second extension area 223, and the welding area 221 is located on the first extension region 222 and the second extension region 223 . The insulating layer 30 is provided with windows 31 corresponding to the positions of the plurality of pads 20 to expose the soldering regions 221 of the second surface 22 of the plurality of soldering pads 20 and between the plurality of soldering regions 221 The gap 25, that is, one window 31 of the insulating layer 30 corresponds to a plurality of pads 20, and the plurality of pads 20 are arranged in a row. The insulating layer 30 extends from the circuit board main body 10 to the first extension region 222 and the second extension region 223 of the pad 20 via the third surface 23 and the fourth surface 24 respectively, that is to say, the window 31 of the insulating layer 30 The long-side boundary of the pad 20 is on the first extension region 222 and the second extension region 223, while the short-side boundary is outside the pad 20, that is, the insulating layer 30 covers the third surface 23, the second extension region 20 of the pad 20. The four surfaces 24, the first extension region 222 and the second extension region 223 make the insulating layer 30 have a binding force on the pad 20, thereby strengthening the fixing force of the pad 20 attached to the main body 10 of the circuit board, so that welding on the pad When the connector (not shown in the figure) on 20 is plugged into the motherboard of the electronic device, the pad 20 is not easy to fall off, and at the same time prevents the wire (not shown) connected to the pad from being exposed to avoid short circuit, that is to say, Since the edge of the insulating layer 30 overlaps the first extension region 222 and the second extension region 223 of the pad 20 , the wire connected to the pad 20 will not be exposed, thereby avoiding short circuit. In addition, one end of the third surface 23 is connected to the first extension area 222, and the other end is connected to the first surface 21; one end of the fourth surface 24 is connected to the second extension area 223, and the other end is connected to the first surface 21; the third surface 23 and the first surface 21 forms an included angle α in the range of 45° to 85°, and the fourth surface 24 and the first surface 21 form an included angle β in the range of 45° to 85°, so that the area of the first surface 21 of the pad 20 larger than the area of the second surface 22 of the pad. The area of the second surface 22 is the actual required area for welding. In order to match the connecting terminals of the connector (not shown), the variable range of the area of the second surface 22 is very limited, while the first surface 21 does not need to be matched with any parts, so its area can vary greatly. Therefore, in the embodiment of the present invention, the area of the first surface 21 is set to be larger than the area actually required for welding, that is, the area of the first surface 21 is set to The area is larger than that of the second surface 22 , so as to increase the bonding force between the pad 20 and the main body 10 of the circuit board, and further prevent the pad 20 from falling off. In this embodiment, the widths of the first surface 21 and the second surface 22 of the pad 20 along the extending direction of the cutting line A-A are equal, and in the extending direction of the cutting line B-B, the length of the first surface 21 is greater than that of the second surface 22, so that the area of the first surface 21 is greater than the area of the second surface 22, thereby increasing the contact area between the pad 20 and the main body of the circuit board, thereby increasing the distance between the pad 20 and the main body of the circuit board 10 The bonding force further prevents the pad from falling off during the connector insertion and removal process.

Please refer to FIG. 3 . FIG. 3 is a schematic cross-sectional view of the circuit board along the section line B-B in FIG. 2 a according to the second embodiment of the present invention. The structure of the circuit board in this embodiment (i.e. the second embodiment) is basically the same as the structure of the circuit board described in the accompanying drawings corresponding to the first embodiment and the first embodiment, the difference is that in this embodiment The circuit board also includes a reinforcing layer 40, the reinforcing layer 40 is respectively arranged between the insulating layer 30 and the third surface 23 and between the insulating layer 30 and the fourth surface 24, and respectively extends to the circuit board main body 10, that is, the reinforcing layer 40 is disposed between the insulating layer and the third surface 23 , the fourth surface 24 of the pad 20 , and the circuit board main body 10 . In one embodiment, the section of the reinforcement layer 40 perpendicular to the main body of the circuit board and the third surface is triangular, that is, the section of the reinforcement layer 40 along the cutting line B-B is a triangle. In this embodiment, the reinforcing layer 40 covers the third surface 23 and the fourth surface 24 , but does not extend to the first surface 21 of the bonding pad 20 , that is, the thickness of the reinforcing layer 40 is equal to the thickness of the bonding pad 20 . The reinforcement layer 40 is a transparent optical adhesive layer, the transparent optical adhesive layer (reinforcement layer 40) has viscosity and toughness, it is arranged between the insulating layer 30 and the third surface 23, the fourth surface 24 and toward the circuit board main body 10 Extending, so that the pad 20 and the circuit board main body 10 and the insulating layer 30 are closely integrated, thereby further preventing the pad 20 from falling off.

Please refer to Fig. 4a and Fig. 4b, Fig. 4a is a schematic cross-sectional view of the circuit board along the section line A-A in Fig. 2a in the third embodiment of the present invention; Fig. 4b is a schematic cross-sectional view of the circuit board along the section line B-B in Fig. 2a in the third embodiment of the present invention cross-sectional schematic diagram. The structure of the circuit board in this embodiment (the third embodiment) is basically the same as the structure of the circuit board described in the second embodiment and its corresponding drawings, the difference is: the thickness of the reinforcement layer 40 in this embodiment It is also disposed in the gap 25 between the pads 20 , and the thickness of the reinforcing layer 40 disposed in the gap 25 between the pads 20 is less than or equal to the thickness of the pad 20 . That is to say, the reinforcing layer 40 is arranged around the outer wall of the pad 20 to make the pad 20 and the circuit board main body 10 more closely integrated, so as to further prevent the pad from falling off. Preferably, the reinforcing layer 40 is set as a transparent optical adhesive layer, which can increase the bonding force between the pads 20 and the circuit board main body 10, and can also insulate the pads 20, because it is transparent , will not affect the alignment accuracy when the connector is mounted.

Please refer to FIG. 5 . FIG. 5 is a schematic cross-sectional view of the circuit board along the section line B-B in FIG. 2 a according to the fourth embodiment of the present invention. The structure of the circuit board in this embodiment (i.e. the fourth embodiment) is basically the same as the structure of the circuit board described in the third embodiment and its corresponding drawings, the difference is: the reinforcement layer of the circuit board in this embodiment 40 extends from the third surface 23 of the pad 20 to the first extension region 222, and the reinforcement layer 40 extends from the fourth surface 24 to the second extension region 223, the edge of the reinforcement layer 40 and the edge of the insulating layer 30 at the window 31 flush, or the edge of the reinforcing layer 40 is retracted toward the side of the main body 10 of the circuit board relative to the insulating layer 30 . That is to say, the reinforcing layer 40 extends to the edge of the second surface 22 of the solder pad 20 , constrains the solder pad 20 to the side of the circuit board main body 10 , thereby further preventing the solder pad 20 from falling off. In this embodiment, preferably, the reinforcing layer 40 is set as a transparent optical adhesive layer, and the gap 25 between the pads 20 is provided with a transparent optical adhesive layer. At this time, the thickness of the transparent optical adhesive layer can be greater than that of the pads 20 Thickness, which can more effectively prevent short circuit between pads without affecting the alignment accuracy when the connector is mounted.

Please refer to Figure 6a and Figure 6b, Figure 6a is a partial enlarged view of the circuit board in the fifth embodiment of the present invention corresponding to part e in Figure 1; Figure 6b is a section line C-C of the circuit board in Figure 6a in the fifth embodiment of the present invention cross-sectional schematic diagram. The structure of the circuit board in this embodiment (i.e. the fifth embodiment) is basically the same as the structure of the circuit board described in the third embodiment and its corresponding drawings, the difference is that in this embodiment, multiple The pads 20 are arranged in a queue, and the area of the pads 20 positioned at both ends of one of the queues is larger than the area of the other pads 20, and the short side boundaries of the window 31 of the insulating layer 30 are arranged on the pads at the two ends of the queue. above, that is, the insulating layer 30 covers the first extension area, the second extension area and a part of the welding area of the pads at both ends of the array. The area of the pads 20 at both ends of the queue increases, which not only increases the bonding area between the pads 20 and the circuit board main body 10, but also increases the area where the insulating layer 30 covers the pads 20, thereby further preventing the pads from falling off. , to avoid affecting the signal transmission between the connector and the circuit board.

In an embodiment of the present invention, the main body of the circuit board is a flexible board or a rigid board.

In an embodiment of the present invention, the insulating layer is solder resist ink, a cover layer or other polymer films.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples" or "some examples" mean specific features described in connection with the embodiment or example, A structure, material or characteristic is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The implementation methods described above do not constitute a limitation to the scope of protection of the technical solution. Any modifications, equivalent replacements and improvements made within the spirit and principles of the above implementation methods shall be included in the protection scope of the technical solution.

Claims (10)

1. a kind of circuit board, it is characterised in that multiple including circuit board main body, multiple pads and insulating barrier The pad and the insulating barrier are arranged in the circuit board main body, and the pad includes for being oppositely arranged One surface and second surface, the first surface fits in the circuit board main body, and the second surface includes Weld zone, the first extension area and the second extension area, the weld zone is located at first extension area and described the Between two extension areas, the position of the corresponding multiple pads of the insulating barrier offers window, multiple to expose Gap between the weld zone of the second surface of the pad and multiple weld zones, the insulating barrier Cover first extension area and second extension area.

2. circuit board as claimed in claim 1, it is characterised in that the area of the first surface is more than institute State the area of second surface.

3. circuit board as claimed in claim 2, it is characterised in that the pad also include the 3rd surface and 4th surface, the 3rd surface and the 4th surface are arranged relatively, the 3rd surface one end connection First extension area, the other end connects the first surface, the 4th surface one end connection described second Extension area, the other end connects the first surface, and the 3rd surface is at 45 ° with the first surface to 85 ° In the range of angle, the 4th surface angle to 85 ° in the range of at 45 ° with the first surface.

4. the circuit board as described in any one of claims 1 to 3, it is characterised in that the circuit board is also wrapped Back-up coat is included, the back-up coat is respectively arranged between the insulating barrier and the 3rd surface and described exhausted Between edge layer and the 4th surface, and respectively to circuit board main body extension.

5. circuit board as claimed in claim 4, it is characterised in that the back-up coat is transparent optical glue-line.

6. circuit board as claimed in claim 5, it is characterised in that the back-up coat is also provided at the weldering Gap between the weld zone of disk, the thickness of the back-up coat in the gap being arranged between the pad is less than Or equal to the thickness of the pad.

7. circuit board as claimed in claim 4, it is characterised in that the back-up coat is by the 3rd surface Extend to first extension area, the back-up coat is extended from the 4th surface to second extension area.

8. circuit board as claimed in claim 4, it is characterised in that the plurality of pad is arranged in queue, Area positioned at the pad at the two ends of a queue is bigger than the area of other pads in the queue.

9. circuit board as claimed in claim 4, it is characterised in that the back-up coat perpendicular to the electricity The section on road plate main body and the 3rd surface is triangle.

10. the circuit board as described in any one of claim 5 to 9, it is characterised in that the circuit board master Body is flexible board or hardboard.