WO2021119990A1

WO2021119990A1 - Flexible circuit board

Info

Publication number: WO2021119990A1
Application number: PCT/CN2019/125933
Authority: WO
Inventors: 杨桂霞
Original assignee: 瑞声声学科技(深圳)有限公司; 瑞声科技(新加坡)有限公司
Priority date: 2019-12-17
Filing date: 2019-12-17
Publication date: 2021-06-24

Abstract

Provided is a flexible circuit board, including: a substrate (11), an upper circuit (12) and a lower circuit (13) being fixed on the substrate (11), and a conduction hole (14) penetrating the surface of the upper circuit (12) and the surface of the lower circuit (13); the conduction hole (14) contains a conductor, the upper layer circuit (12) and the lower layer circuit (13) are electrically connected by means of the conductor; the upper layer circuit (12) at least comprises: an upper layer transmission part (121) and an upper layer connection part (122) electrically connected to the upper layer transmission part (121); the lower layer circuit (13) at least comprises: a lower layer transmission part (131) and a lower layer connection part (132) electrically connected to the lower layer transmission part (131), the upper layer connecting part (122) and the lower layer connection part (132) respectively covering the two sides of the same part of the substrate (11) to form a circuit board connection part; the circuit board connection part is provided with at least two conduction holes (14), and the upper layer circuit (12) and the lower layer circuit (13) are electrically connected by means of the conductor in the conduction holes (14). The plurality of conduction holes can prevent the electrical connection between the upper layer circuit (12) and the lower layer circuit (13) being blocked as a result of damage to the conduction holes, thus the reliability of the conduction between the upper layer circuit (12) and the lower layer circuit (13) is improved.

Description

Flexible circuit board

Technical field

The utility model relates to the field of through holes of flexible circuit boards, in particular to a flexible circuit board.

Background technique

FPC(Flexible Printed Circuit (flexible circuit board) is generally divided into double-panel or multi-panel in design. Specifically, the flexible circuit board is composed of an upper circuit, a lower circuit and a substrate board. The upper circuit and the lower circuit are respectively arranged on the front and back of the substrate board, and are electrically connected by the upper circuit and the lower circuit to form a loop.

In the prior art, a through hole is usually provided symmetrically on the front and back of the substrate plate, so that the upper layer circuit and the lower layer circuit are electrically connected through the through hole, thereby forming a loop. However, in the process of processing, the via holes may be easily damaged or partially broken due to the presence of foreign matter and other impurities in the via holes, which may cause the upper and lower layers to fail to conduct or present reliability risks.

Therefore, it is necessary to provide a new flexible circuit board.

technical problem

The purpose of the utility model is to provide a flexible circuit board to solve the technical problem that the through holes are easily damaged or the partial holes are broken in the prior art, which causes the upper and lower layers to fail to conduct.

Technical solutions

The technical solution of the present invention is as follows: a flexible circuit board comprising: a substrate board, an upper circuit fixed on one surface of the substrate board, and the upper circuit fixed on the opposite side of the upper circuit The lower layer circuit on the other surface of the substrate board, and the via hole penetrating the surface of the upper layer circuit and the surface of the lower layer circuit, the via hole contains a conductor, the upper layer circuit and the lower layer circuit Through the electrical connection of the conductor in the via hole, the upper-layer circuit at least includes: an upper-layer transmission portion and an upper-layer connection portion electrically connected to the upper-layer transmission portion, and the lower-layer circuit at least includes: a lower-layer transmission portion and A lower connection part electrically connected to the lower transmission part, the upper connection part and the lower connection part respectively cover both sides of the same part of the base plate to form a circuit board connection part;

The circuit board connection portion is provided with at least two through holes, and the upper layer circuit and the lower layer circuit are electrically connected through the conductor in the through hole.

Optionally, the circuit board connection portion is provided with at least two through holes.

Optionally, the via hole is provided with a first via hole and a second via hole, and the first via hole and the second via hole are arranged on the circuit board connecting portion toward the The upper line extends on the same horizontal line as the connection.

Optionally, the electrical conductor is attached to the sidewall of the via hole, one end of the electrical conductor perpendicularly penetrates the surface of the lower line from the surface of the upper line, and one end of the electrical conductor is connected to the surface of the lower line. The upper layer circuit is electrically connected, and the other end of the conductor is electrically connected with the lower layer circuit.

Optionally, the conductive body is a cylindrical conductive ring, and the outer side surface of the conductive ring is attached to the side wall of the via hole.

Optionally, the conductive body is a strip-shaped conductive strip, and one side of the conductive strip is attached to the side wall of the via hole.

Optionally, the material of the conductor is a copper material.

Beneficial effect

The beneficial effect of the present invention is to provide a flexible circuit board, the flexible circuit board comprising: a substrate board, an upper circuit fixed on a surface of the substrate board, fixed on the opposite side of the upper circuit The lower layer circuit on the other surface of the substrate board and the via hole penetrating the surface of the upper layer circuit and the surface of the lower layer circuit, the via hole contains a conductor, the upper layer circuit and the lower layer The circuit is electrically connected by the conductor in the via hole, the upper layer circuit at least includes: an upper layer transmission portion and an upper layer connection portion electrically connected to the upper layer transmission portion, and the lower layer circuit at least includes: a lower layer transmission portion And a lower connection part electrically connected to the lower transmission part, the upper connection part and the lower connection part respectively cover both sides of the same part of the base plate to form a circuit board connection part; the circuit board connection The portion is provided with at least two through holes, and the upper layer circuit and the lower layer circuit are electrically connected through the conductor in the through hole. By arranging a plurality of through holes in the circuit board connection part of the flexible circuit board, the through holes can be prevented from being damaged and the electrical connection between the upper layer circuit and the lower layer circuit is blocked, and the upper layer is improved. The reliability of the connection between the circuit and the lower-layer circuit.

Description of the drawings

Figure 1 is a schematic diagram of the front structure of a flexible circuit board provided by the utility model;

Figure 2 is a schematic diagram of the backside structure of a flexible circuit board provided by the utility model;

Figure 3 is a partial enlarged view of the front structure schematic diagram of the flexible circuit board of the present invention;

Fig. 4 is a partial enlarged view of the schematic diagram of the back structure of the flexible circuit board of the present invention.

Embodiments of the present invention

The present utility model will be further explained below in conjunction with the drawings and embodiments.

Please refer to Figure 1, Figure 2, Figure 3 and Figure 4. Figure 1 is a schematic diagram of the front structure of a flexible circuit board provided by the present invention, and Figure 2 is a schematic diagram of the back structure of a flexible circuit board provided by the present invention. Figure 3 It is a partial enlarged view of the schematic diagram of the front structure of the flexible circuit board of the present invention, and FIG. 4 is a partial enlarged view of the schematic diagram of the back structure of the flexible circuit board of the present invention.

The technical solution of the present invention is as follows: a flexible circuit board comprising: a substrate board 11, an upper circuit 12 fixed on one surface of the substrate board 11, and a substrate board fixed on the opposite side of the upper circuit 12 11 The lower layer circuit 13 on the other surface, and the via hole 14 penetrating the surface of the upper layer circuit 12 and the surface of the lower layer circuit 13, the via hole 14 contains a conductor, and the upper layer circuit 12 and the lower layer circuit 13 pass through the via hole 14 The upper layer line 12 includes at least: an upper layer transmission portion 121 and an upper layer connection portion 122 electrically connected to the upper layer transmission portion 121, and the lower layer line 13 at least includes: a lower layer transmission portion 131 and an upper layer connection portion 131 electrically connected to the lower layer transmission portion 131 The lower connection portion 132, the upper connection portion 122 and the lower connection portion 132 respectively cover both sides of the same part of the base plate 11 to form a circuit board connection portion;

The circuit board connection portion is provided with at least two via holes 14, and the upper layer circuit 12 and the lower layer circuit 13 are electrically connected through the conductor in the via hole 14.

In the embodiment of the present invention, the flexible circuit board includes: a substrate board 11, an upper circuit 12 and a lower circuit 13 located on the front and back of the substrate board 11, an upper connection portion 122 of the upper circuit and a lower connection portion of the lower circuit 132 respectively covers both sides of the same part of the base plate 11, and the covered same part is used as the circuit board connection part. The circuit board connection part structurally includes at least the upper layer connection part 122 and the part covered by both sides of the base plate 11 The lower connection portion 132 is provided with a plurality of via holes 14 containing conductors in the circuit board connection portion. The via hole 14 can be made by laser hole formation or plasma etching, etc. It should be noted that When the via hole 14 is made, it is necessary to drill the upper connection portion 122 of the circuit board connection portion, the part covered by both sides of the base plate 11, and the lower connection portion 132 together, so that the via hole 14 penetrates the circuit board connection Part; and a conductor is provided in the via hole 14, so that the upper layer circuit 12 is electrically connected to the lower layer circuit 13 through the conductor in the via hole 14.

Furthermore, the circuit board connection part is provided with at least two via holes 14. In the embodiment of the present invention, a plurality of through holes 14 may be provided in the circuit board connection part. Preferably, the circuit board connection part in this embodiment is provided with at least two through holes 14 to effectively avoid one of them. The via hole 14 is damaged or part of the hole is broken, causing the upper-layer circuit 12 and the lower-layer circuit 13 to be unable to be electrically connected or to be blocked; the arrangement of the via-hole 14 in this embodiment can improve the distance between the upper-layer circuit 12 and the lower-layer circuit 13 The electrical connection increases reliability.

Further, the via hole 14 is provided with a first via hole 141 and a second via hole 142. The first via hole 141 and the second via hole 142 are arranged in the circuit board connection part to extend and connect to the upper layer circuit 12. The horizontal line in the same direction. In the embodiment of the present invention, the arrangement of the multiple vias 14 in the circuit board connection part should consider the flexibility of the upper circuit 12 and the lower circuit 13 on the flexible circuit board, so as to minimize the flexibility of the flexible circuit board or The upper layer circuit 12 and the lower layer circuit 13 are broken or cracked; preferably, this embodiment includes a first via 141 and a second via 142, and the circuit board connection portion includes: an upper circuit board connection portion and a lower circuit board In the connecting portion, the first via hole 141 and the second via hole 142 are arranged on the same horizontal line in the same direction that the upper layer circuit board connection portion extends and connects to the upper layer circuit 12. At the same time, the first via hole 141 and the second via hole 141 The two vias 142 are also arranged on the same horizontal line in the same direction that the lower circuit board connection portion extends and connects to the lower layer circuit 13, wherein the first via hole 141 is located at the circuit board connection portion near the extension connection with the upper circuit 12 One end, and the second through hole 142 is located at the end of the circuit board connection part away from the extended connection with the upper layer circuit 12.

Further, the electrical conductor is attached to the sidewall of the via hole 14, one end of the electrical conductor penetrates from the surface of the upper connection portion 122 to the surface of the lower connection portion 132 perpendicularly, and one end of the electrical conductor is electrically connected to the upper connection portion 122. The other end of the body is electrically connected to the lower connection portion 132.

Further, the conductive body is a cylindrical conductive ring, and the outer side of the conductive ring is attached to the side wall of the through hole 14. In this embodiment, the conductive body in the through hole 14 may be a cylindrical conductive ring. The conductive ring is a hollow cylindrical conductive body, the outer side of the conductive ring is attached to the side wall of the through hole 14, and the cross section of the conductive ring and the cross section of the through hole 14 are on the same horizontal plane, and The cross-sections are all round; one end of the conductive ring is electrically connected to the upper connection portion 122, and extends vertically from the end connected to the upper connection portion 122 to the lower connection portion 132, and is electrically connected to the lower connection portion 132.

Further, the conductive body is a strip-shaped conductive strip, and the conductive strip is attached to the side wall of the via hole 14. In this embodiment, the conductive body in the via hole 14 can be a strip-shaped conductive strip. The conductive strip is a strip-shaped conductive body with conductive properties. Specifically, the conductive strip can be a wire, a tin strip, or a conductive strip. Conductors with conductive properties, such as a sheet, preferably, a strip-shaped conductive sheet is used in this embodiment. One end of the conductive strip is electrically connected to the upper connection portion 122 and extends vertically from the end connected to the upper connection portion 122 to the lower connection Part 132, and is electrically connected to the lower connection part 132.

Further, the material of the conductor is copper material. In this embodiment, the conductor in the via hole 14 is made of Cu (copper) material. Because the copper material product has better conductivity and has certain flexibility, it can realize the upper circuit 12 and the lower layer. The circuit 13 is conductive, and at the same time, the reliability of the process of making the via hole 14 is improved, and the damage of the via hole 14 is avoided to a certain extent; the conductor of the above embodiment is made of copper material, such as the conductive ring and the conductive strip in the above embodiment , So that the upper layer circuit 12 and the lower layer circuit 13 of the flexible circuit board are electrically connected by a copper conductor with better conductivity.

The utility model provides a flexible circuit board. The flexible circuit board includes a substrate board, an upper circuit fixed on one surface of the substrate board, a lower circuit fixed on the other surface of the substrate board opposite to the upper circuit, and a self-contained circuit board. The surface of the upper layer circuit is a via hole penetrating the surface of the lower layer circuit. The via hole contains a conductor. The upper layer circuit and the lower layer circuit are electrically connected by the conductor in the via hole. The upper layer circuit at least includes: an upper layer transmission part and an upper layer The upper connection part electrically connected to the transmission part, the lower circuit at least includes: a lower transmission part and a lower connection part electrically connected to the lower transmission part, the upper connection part and the lower connection part respectively cover both sides of the same part of the base plate to form a circuit Board connection part; the circuit board connection part is provided with a plurality of through holes, the through holes respectively penetrate from the surface of the upper circuit to the surface of the lower circuit, so that the upper circuit and the lower circuit are electrically connected through the conductor in the through hole. By arranging a plurality of through holes in the circuit board connection part of the flexible circuit board, the through holes can be prevented from being damaged and the electrical connection between the upper layer line and the lower layer line is blocked, and the reliability of the conduction of the upper layer line and the lower layer line is improved.

The above are only the embodiments of the present utility model. It should be pointed out here that for those of ordinary skill in the art, improvements can be made without departing from the inventive concept of the present utility model, but these all belong to The scope of protection of the utility model.

Claims

A flexible circuit board, the flexible circuit board comprising: a substrate board, an upper circuit fixed on one surface of the substrate board, a lower circuit fixed on the other surface of the substrate board, and penetrating through the upper layer The via hole on the surface of the circuit and the surface of the lower layer circuit, the via hole contains a conductor, the upper layer circuit and the lower layer circuit are electrically connected by the conductor in the via hole, and It is characterized in that the upper layer line at least includes: an upper layer transmission part and an upper layer connection part electrically connected to the upper layer transmission part, and the lower layer line at least includes: a lower layer transmission part and a lower layer connection part electrically connected to the lower layer transmission part , The upper connecting portion and the lower connecting portion respectively cover both sides of the same part of the base plate to form a circuit board connecting portion;

The circuit board connection portion is provided with at least two through holes, and the upper layer circuit and the lower layer circuit are electrically connected through the conductor in the through hole.
The flexible circuit board according to claim 1, wherein the circuit board connection portion is provided with two through holes.
The flexible circuit board according to claim 2, wherein the via hole is provided with a first via hole and a second via hole, the first via hole and the second via hole row They are arranged on the same horizontal line extending and connecting the circuit board connection part to the upper layer circuit.
The flexible circuit board according to claim 1, wherein the conductive body is attached to the side wall of the via hole, and one end of the conductive body penetrates the lower layer perpendicularly from the surface of the upper layer circuit. On the surface of the circuit, one end of the conductor is electrically connected with the upper-layer circuit, and the other end of the conductor is electrically connected with the lower-layer circuit.
4. The flexible circuit board according to claim 4, wherein the conductor is a cylindrical conductive ring, and the outer side surface of the conductive ring is attached to the side wall of the via hole.
4. The flexible circuit board according to claim 4, wherein the conductive body is a strip-shaped conductive strip, and one side of the conductive strip is attached to the side wall of the via hole.
The flexible circuit board according to claim 5 or 6, wherein the material of the conductor is a copper material.