Connection structure, flexible wiring board, and board member

Abstract

To provide a connection structure in which a plurality of wires can be arranged at a high density while deterioration in high frequency characteristics is prevented.SOLUTION: A connection structure includes a first flexible wiring board and a board member. The first flexible wiring board has a first base film, a plurality of first wires, and a plurality of first electrodes. The first base film includes a first main surface extending along a first direction. The first electrodes are each electrically connected to a corresponding one of the first wires. The board member has a board body and a first connector. The board body includes a third main surface. The third main surface extends along a second direction. The first connector includes a plurality of first conductors. The first flexible wiring board is coupled to the first connector such that the first direction intersects the second direction obliquely. Each of the first electrodes is electrically connected to a corresponding one of the first conductors when the first flexible wiring board is coupled to the first connector.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a connection structure, a flexible printed circuit board, and a substrate member.

Background Art

[0002] Patent Document 1 discloses a connection structure including a printed circuit board and a flexible printed circuit board horizontally connected to the printed circuit board. The flexible printed circuit board has a plurality of leads arranged along one direction. The plurality of leads are respectively connected to corresponding terminals among a plurality of terminals of the leads on the printed circuit board.

[0003] Patent Document 2 discloses a connection structure including a main substrate and a plurality of connection substrates vertically connected to the main substrate. Each connection substrate has a plurality of conductor patterns arranged along one direction. The plurality of conductor patterns are respectively connected to the wiring of the main substrate via pin terminals (main substrate side connection terminal portions).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the connection structure described in Patent Document 1, the flexible printed circuit board is connected horizontally to the printed circuit board. In this case, it is difficult to arrange a plurality of leads in the flexible printed circuit board not only in a direction parallel to the printed circuit board but also in a vertical direction. As a result, it is difficult to arrange a plurality of leads at high density in the flexible printed circuit board. Further, in the connection structure described in Patent Document 1, each lead in the flexible printed circuit board is connected to each terminal on the printed circuit board via a contact spring. As a result, the connection structure between the lead and the terminal becomes complicated, so that the high-frequency characteristics deteriorate.

[0006] When connecting the conductive pattern in the connection substrate and the wiring of the main substrate using a connector such as a pin terminal as in the connection structure described in Patent Document 2, by connecting the connection substrate perpendicular to the main substrate, a plurality of conductive patterns can be arranged in two directions, and a plurality of conductive patterns can be arranged at high density. However, since the structure in which the conductive pattern and the wiring are electrically connected using a pin terminal is complicated, the high-frequency characteristics in the connection structure still deteriorate.

[0007] An object of the present disclosure is to provide a connection structure, a flexible printed circuit board, and a substrate member capable of arranging a plurality of wirings at high density while suppressing deterioration of high-frequency characteristics.

Means for Solving the Problems

[0008] A connection structure according to an embodiment of the present disclosure includes a first flexible printed circuit board, a second flexible printed circuit board, and a substrate member. The first flexible printed circuit board has a first base film, a plurality of first wirings, and a plurality of first electrode portions. The first base film includes a first main surface extending along a first direction. The plurality of first wirings are provided in or on the first base film. The plurality of first electrode portions are provided on the first main surface at a tip portion of the first base film in the first direction. The plurality of first electrode portions are electrically connected to corresponding first wirings among the plurality of first wirings, respectively. The second flexible printed circuit board has a second base film, a plurality of second wirings, and a plurality of second electrode portions. The second base film includes a second main surface extending along the first direction. The plurality of second wirings are provided in or on the second base film. The plurality of second electrode portions are provided on the second main surface at a tip portion of the second base film in the first direction. The plurality of second electrode portions are electrically connected to corresponding second wirings among the plurality of second wirings, respectively. The second flexible printed circuit board is arranged side by side with the first flexible printed circuit board along a second direction. The substrate member has a substrate body, a first connector, and a second connector. The substrate body includes a third main surface. The third main surface extends along the second direction. The third main surface faces the first main surface and the second main surface. The first connector is provided on the third main surface. The first connector includes a plurality of first conductors. The second connector is provided on the third main surface. The second connector includes a plurality of second conductors. The first connector and the second connector are arranged side by side along the second direction. The first flexible printed circuit board is coupled to the first connector such that the first direction in which the first main surface extends intersects obliquely with respect to the second direction. The second flexible printed circuit board is coupled to the second connector such that the first direction in which the second main surface extends intersects obliquely with respect to the second direction. When the first flexible printed circuit board is coupled to the first connector, each of the plurality of first electrode portions is electrically connected to a corresponding first conductor among the plurality of first conductors. Each of the plurality of second electrode portions is electrically connected to a corresponding second conductor among the plurality of second conductors when the second flexible printed circuit board is coupled to the second connector.

Advantages of the Invention

[0009] According to the present disclosure, while suppressing deterioration of high-frequency characteristics, a plurality of wirings can be arranged at high density.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0011] [Description of Embodiment of the Present Disclosure] First, the content of the embodiment of the present disclosure will be listed and described. [1]The connection structure according to an embodiment includes a first flexible printed circuit board, a second flexible printed circuit board, and a substrate member. The first flexible printed circuit board has a first base film, a plurality of first wirings, and a plurality of first electrode portions. The first base film includes a first main surface extending along a first direction. The plurality of first wirings are provided in or on the first base film. The plurality of first electrode portions are provided on the first main surface at the tip portion of the first base film in the first direction. The plurality of first electrode portions are electrically connected to the corresponding first wirings among the plurality of first wirings respectively. The second flexible printed circuit board has a second base film, a plurality of second wirings, and a plurality of second electrode portions. The second base film includes a second main surface extending along the first direction. The plurality of second wirings are provided in or on the second base film. The plurality of second electrode portions are provided on the second main surface at the tip portion of the second base film in the first direction. The plurality of second electrode portions are electrically connected to the corresponding second wirings among the plurality of second wirings respectively. The second flexible printed circuit board is arranged side by side with the first flexible printed circuit board along a second direction. The substrate member has a substrate body, a first connector, and a second connector. The substrate body includes a third main surface. The third main surface extends along the second direction. The third main surface faces the first main surface and the second main surface. The first connector is provided on the third main surface. The first connector includes a plurality of first conductors. The second connector is provided on the third main surface. The second connector includes a plurality of second conductors. The first connector and the second connector are arranged side by side along the second direction. The first flexible printed circuit board is coupled to the first connector such that the first direction in which the first main surface extends intersects obliquely with respect to the second direction. The second flexible printed circuit board is coupled to the second connector such that the first direction in which the second main surface extends intersects obliquely with respect to the second direction. When the first flexible printed circuit board is coupled to the first connector, each of the plurality of first electrode portions is electrically connected to the corresponding first conductor among the plurality of first conductors. When the second flexible printed circuit board is coupled to the second connector, each of the plurality of second electrode portions is electrically connected to the corresponding second conductor among the plurality of second conductors.

[0012] In this connection structure, the first flexible printed circuit board and the second flexible printed circuit board are arranged side by side along the second direction. The first flexible printed circuit board is coupled to the first connector such that the first direction in which the first main surface extends intersects obliquely with respect to the second direction. The second flexible printed circuit board is coupled to the second connector such that the first direction in which the second main surface extends intersects obliquely with respect to the second direction. According to this connection structure, since the first flexible printed circuit board and the second flexible printed circuit board extend in the first direction that intersects the second direction, interference between the first flexible printed circuit board and the second flexible printed circuit board when they are arranged side by side along the second direction is suppressed. Thereby, the first flexible printed circuit board and the second flexible printed circuit board can be arranged at high density along the second direction. As a result, a plurality of wirings can be arranged at high density not only in the third direction intersecting the first direction and the second direction but also in the second direction. Further, in the above-described connection structure, each of the plurality of first electrode portions is electrically connected to a corresponding first conductor among the plurality of first conductors when the first flexible printed circuit board is coupled to the first connector. And each of the plurality of second electrode portions is electrically connected to a corresponding second conductor among the plurality of second conductors when the second flexible printed circuit board is coupled to the second connector. According to this connection structure, the wirings in the plurality of flexible printed circuit boards and the conductors in the plurality of connectors can be electrically connected with a simple structure. Thereby, deterioration of high-frequency characteristics in the connection structure can be suppressed. From the above, while suppressing deterioration of high-frequency characteristics in the connection structure, a plurality of wirings can be arranged at high density. In addition, since the plurality of flexible printed circuit boards are respectively coupled to the plurality of connectors such that the first direction intersects obliquely with respect to the second direction, the length along the direction orthogonal to the first direction of the connection structure is reduced. Thereby, the connection structure can be made lower in height.

[0013] [2] In the connection structure of [1] above, the inclination angle of the second flexible printed circuit board with respect to the second direction may be in a range smaller than the inclination angle of the first flexible printed circuit board with respect to the second direction. In this case, it is possible to suppress interference between the first flexible printed circuit board and the second flexible printed circuit board. As a result, a plurality of flexible printed circuit boards can be arranged at high density, so that a plurality of wirings can be arranged at even higher density.

[0014] [3] In the connection structure of [1] or [2] above, the first connector may include a main body portion and a fixing member that fixes the first flexible printed circuit board to the main body portion in a state where the first flexible printed circuit board is coupled to the first connector. In this case, when the first flexible printed circuit board is coupled to the first connector, each of the plurality of first electrode portions can be stably electrically connected to the corresponding first conductor among the plurality of first conductors.

[0015] [4] In the connection structure of [3] above, the first connector may include a plurality of holding holes that penetrate the main body portion and into which the plurality of first conductors are respectively inserted. In this case, when the first flexible printed circuit board is coupled to the first connector, each of the plurality of first electrode portions can be even more stably electrically connected to the corresponding first conductor among the plurality of first conductors.

[0016] [5] In the connection structure of any one of [1] to [4] above, the second connector may be located between the first main surface of the first base film of the first flexible printed circuit board and the third main surface of the substrate body of the substrate member. The second connector may include a first end portion and a second end portion arranged along the second direction. The second end portion may be located on the side opposite to the first connector with respect to the first end portion. The distance between the first main surface and the third main surface may be greater than or equal to one time the length of the second connector along the second direction at the first end portion. In this case, a plurality of wirings can be arranged at even higher density.

[0017] [6] In any one of the connection structures [1] to [5] above, each of the plurality of first electrode portions may include an electrode pad that is electrically connected to a corresponding first wiring among the plurality of first wirings, and a bump provided on the electrode pad. In this case, the wiring in the flexible printed circuit board and the conductor in the connector can be electrically connected with a simpler structure. Thereby, deterioration of high-frequency characteristics in the connection structure can be further suppressed.

[0018] [7] In the connection structure of [6] above, some of the plurality of first electrode portions may be a plurality of third electrode portions arranged along a third direction intersecting the first direction and the second direction. Some of the other first electrode portions among the plurality of first electrode portions may be a plurality of fourth electrode portions arranged along the third direction and located on the side opposite to the tip of the tip portion of the base film with respect to the plurality of third electrode portions. The maximum value of the length along the fourth direction of the bump included in each of the plurality of fourth electrode portions may be larger than the maximum value of the length along the fourth direction of the bump included in each of the plurality of third electrode portions. In this case, when the first flexible printed circuit board is coupled to the first connector such that the first direction intersects obliquely with the second direction, the plurality of first electrode portions can stably support the first base film and each of the plurality of first electrode portions can surely contact a corresponding first conductor among the plurality of first conductors. Thereby, each of the plurality of first electrode portions can be stably electrically connected to a corresponding first conductor among the plurality of first conductors.

[0019] [8] In the connection structure of [6] or [7] above, the bump may include a first surface that extends along a first direction and contacts the electrode pad, and a second surface that is located on the side opposite to the first surface with respect to the bump and extends along a second direction. When the first flexible wiring board is coupled to the first connector, the second surface may contact a corresponding first conductor among the plurality of first conductors. In this case, the first flexible wiring board is stably supported by the first connector via a plurality of bumps. Thereby, each of the plurality of electrode portions can be more stably electrically connected to a corresponding conductor among the plurality of conductors.

[0020] [9] In the connection structure of [6] or [7] above, the bump may include a first surface that extends along a first direction and contacts the electrode pad, and a second surface that is located on the side opposite to the first surface with respect to the bump and extends along the first direction. When the first flexible wiring board is coupled to the first connector, the second surface may contact a corresponding first conductor among the plurality of first conductors. In this case, the first flexible wiring board is stably supported by the first connector via a plurality of bumps. Thereby, each of the plurality of electrode portions can be more stably electrically connected to a corresponding conductor among the plurality of conductors.

[0021]

[10] The flexible wiring board according to an embodiment is connectable to a substrate member including a substrate body. The flexible wiring board includes a base film, a plurality of wirings, and a plurality of electrode portions. The base film has a main surface that extends so as to obliquely intersect the direction in which the substrate body extends. The plurality of wirings are provided inside or on the base film. The plurality of electrode portions are provided on the main surface at the tip portion in the direction in which the substrate body of the base film extends. The plurality of electrode portions are each electrically connected to a corresponding wiring among the plurality of wirings. According to the flexible wiring board having such a configuration, the same operational effects as those of the above-described connection structure can be achieved.

[0022]

[11] A flexible printed circuit board according to an embodiment includes a base film, a plurality of wirings, and a plurality of electrode portions. The base film has a main surface. The plurality of wirings are provided in or on the base film. The plurality of electrode portions are provided on the main surface at the tip of the base film. The plurality of electrode portions are electrically connected to corresponding wirings among the plurality of wirings respectively. Each of the plurality of electrode portions has a surface located on the side opposite to the base film, and the surface is inclined with respect to the main surface.

[0023] According to the flexible printed circuit board having such a configuration, the wiring in the flexible printed circuit board and the conductor in the mating connector can be electrically connected with a simpler structure by the electrode portions. Also, while stably electrically connecting each of the plurality of electrode portions to the conductor of the mating connector, it is possible to couple the flexible printed circuit board obliquely to the mating connector. From the above, it is possible to realize a connection structure in which a plurality of wirings can be arranged at high density while suppressing deterioration of high-frequency characteristics.

[0024]

[12] A substrate member according to an embodiment is a substrate member that can be coupled to a plurality of flexible printed circuit boards each including a base film having a first main surface extending along a first direction and a plurality of electrode portions provided on the first main surface. The substrate member has a substrate body and a plurality of connectors. The substrate body has a third main surface extending along a second direction that intersects obliquely with respect to the first direction. The plurality of connectors are arranged along the second direction on the third main surface and each include a plurality of conductors. The plurality of conductors are electrically connected to corresponding electrode portions among the plurality of electrode portions when the connector is coupled to the flexible printed circuit board. According to the substrate member having such a configuration, the same operational effects as those of the above-described connection structure can be achieved.

[0025]

[13] In the substrate member of

[12] above, the connector may have a main body portion and a fixing member that fixes the flexible printed circuit board to the main body portion in a state where the flexible printed circuit board is coupled to the connector. In this case, when the flexible printed circuit board is coupled to the connector, each of the plurality of electrode portions can be stably electrically connected to the corresponding conductor among the plurality of conductors.

[0026] [Details of Embodiments of the Present Disclosure] Specific examples of the connection structure, flexible printed circuit board, and substrate member according to the embodiments of the present disclosure will be described below with reference to the drawings. In the following description, the same reference numerals will be used for the same elements or elements having the same function, and redundant descriptions will be omitted. Note that the present invention is not limited to these examples, and is defined by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0027] FIG. 1 is a perspective view showing a connection structure according to an embodiment. FIG. 2 is a cross-sectional view of the connection structure taken along line II-II shown in FIG. 1. The connection structure 1 includes a plurality of flexible printed circuit boards 2A and 2B, and a substrate member 3. The substrate member 3 has a substrate body 31 and a plurality of connectors 40A and 40B. In the connection structure 1, the plurality of flexible printed circuit boards 2A and 2B are respectively coupled to the plurality of connectors 40A and 40B of the substrate member 3. Hereinafter, the direction in which the flexible printed circuit boards 2A and 2B extend is defined as the A direction (first direction). Also, the directions parallel to the substrate body 31 are defined as the X direction (second direction) and the Y direction (third direction), and the direction perpendicular to the substrate body 31 is defined as the Z direction.

[0028] As shown in FIGS. 1 and 2, a plurality of flexible printed circuit boards 2A and 2B are arranged along the X direction. The plurality of flexible printed circuit boards 2A and 2B are, for example, flexible printed circuits (FPCs). The flexible printed circuit board 2A is coupled to the connector 40A such that the A direction intersects obliquely with respect to the X direction. For example, the flexible printed circuit board 2A is coupled to the connector 40A such that the A direction intersects within a range greater than 10 degrees and less than 80 degrees with respect to the X direction. The flexible printed circuit board 2B is coupled to the connector 40B such that the A direction intersects obliquely with respect to the X direction. The flexible printed circuit board 2B is coupled to the connector 40B such that the A direction intersects within a range greater than 10 degrees and less than 80 degrees with respect to the X direction. The inclination angle of the flexible printed circuit board 2B with respect to the X direction is within a range smaller than the inclination angle of the flexible printed circuit board 2A with respect to the X direction. Note that the angle at which the A direction intersects with respect to the X direction may be within a range greater than 20 degrees and less than 70 degrees, or may be a value greater than 30 degrees and less than 60 degrees.

[0029] The flexible printed circuit board (first flexible printed circuit board) 2A includes a base film (first base film) 21, a plurality of wirings (a plurality of first wirings) 22, and a plurality of electrode portions (a plurality of first electrode portions) 23. The base film 21 is a base layer of the flexible printed circuit board 2A and is formed of, for example, polyimide. The base film 21 has a main surface 21a. The main surface 21a extends along the A direction and the Y direction from the end portion (not shown) of the base film 21 to the tip portion 24.

[0030] FIG. 3 is a view showing the main surface 21a at the tip portion 24 of the base film 21. As shown in FIG. 3, the plurality of wirings 22 are provided inside or on the base film 21. For example, the plurality of wirings 22 may be provided on the main surface 21a of the base film 21 or inside the base film 21. As an example, the plurality of wirings 22 are arranged on the main surface 21a of the base film 21. The plurality of wirings 22 are, for example, conductive patterns or a plurality of high-speed signal paths. Each of the plurality of wirings 22 extends along the A direction. The plurality of wirings 22 are arranged along the Y direction shown in FIG. 2. The plurality of wirings 22 are configured to include at least one metal material among, for example, Au, Ti, Al, Ta, W, Cu, Pt, Mo, Ni, Pd, Zn, and Cr.

[0031] FIG. 4 is an enlarged view of the connector 40A of the connection structure 1 shown in FIG. 2. As shown in FIGS. 3 and 4, the plurality of electrode portions 23 are provided on the main surface 21a at the tip portion 24 in the A direction of the base film 21. The plurality of electrode portions 23 are arranged along the A direction and the Y direction. Each of the plurality of electrode portions 23 is electrically connected to the corresponding wiring 22 among the plurality of wirings 22. Some of the plurality of electrode portions 23 are a plurality of electrode portions (a plurality of third electrode portions) 23a arranged along the Y direction. Some of the other plurality of electrode portions 23 are a plurality of electrode portions (a plurality of fourth electrode portions) 23b arranged along the Y direction. The plurality of electrode portions 23b are located on the side opposite to the tip 24a of the tip portion 24 of the base film 21 with respect to the plurality of electrode portions 23a.

[0032] The plurality of electrode portions 23 are arranged at a density that does not inhibit the high-frequency characteristics of the plurality of wirings 22. For example, the distance between the centers of the plurality of electrode portions 23 is, for example, 2 mm. The plurality of electrode portions 23 are configured to include, for example, Cu. Each of the plurality of electrode portions 23 has an electrode pad 25 and a bump 26.

[0033] The electrode pad 25 is electrically connected to the corresponding wiring 22 among the plurality of wirings 22. The electrode pad 25 is formed in a circular film shape. The electrode pad 25 is composed of, for example, Cu. The bump 26 is provided on the electrode pad 25. The bump 26 is composed of, for example, solder. The electrode pad 25 is electrically and physically connected to the corresponding conductor 42 among the plurality of conductors 42 (described later) by the bump 26. Here, assuming that the direction orthogonal to the main surface 21a is the B direction (the fourth direction), the maximum value of the length of the bump 26 along the B direction included in each of the plurality of electrode portions 23a is larger than the maximum value of the length of the bump 26 along the B direction included in each of the plurality of electrode portions 23b. That is, the maximum value of the length along the B direction of each of the plurality of electrode portions 23a is larger than the maximum value of the length along the B direction of each of the plurality of electrode portions 23b.

[0034] As shown in FIG. 4, the bump 26 has a first surface 26a and a second surface (front surface) 26b arranged along the Z direction. The first surface 26a faces the electrode pad 25 in the Z direction. The first surface 26a extends in the A direction and the Y direction. The first surface 26a contacts the corresponding electrode pad 25 among the plurality of electrode pads 25. The second surface 26b is located on the side opposite to the first surface 26a with respect to the bump 26. The second surface 26b extends along the X direction and the Y direction. The second surface 26b faces the conductor 42 in the Z direction. That is, the second surface 26b is inclined with respect to the main surface 21a. The second surface 26b is located on the side opposite to the base film 21. The second surface 26b electrically and physically contacts the corresponding conductor 42 among the plurality of conductors 42 when the flexible wiring board 2B is coupled to the connector 40A.

[0035] Referring to FIGS. 1 and 2. The flexible wiring board (the second flexible wiring board) 2B has the same configuration as the plurality of flexible wiring boards 2A, and includes a base film (the second base film) 21, a plurality of wirings (a plurality of second wirings) 22, and a plurality of electrode portions (a plurality of second electrode portions) 23. The base film 21 has a main surface (the second main surface) 21a.

[0036] Next, each component of the substrate member 3 will be described. The substrate body 31 extends along the X direction. The substrate body 31 has a main surface (third main surface) 31a. The main surface 31a faces the main surface 21a of the base film 21 in the flexible printed circuit board 2A and the main surface 21a of the base film 21 in the flexible printed circuit board 2B in the Z direction. The main surface 31a extends along the X direction and the Y direction.

[0037] A plurality of connectors 40A, 40B are provided on the main surface 31a of the substrate body 31. The plurality of connectors 40A, 40B are arranged side by side along the X direction on the main surface 31a. The plurality of connectors 40A, 40B are spaced apart from each other by a length L. The connector (first connector) 40A has a body portion 41, a plurality of conductors (a plurality of first conductors) 42, a plurality of holding holes 43, and a fixing member 50.

[0038] The body portion 41 is provided between the tip portion 24 of the base film 21 of the flexible printed circuit board 2A and the main surface 31a of the substrate body 31 of the substrate member 3. The body portion 41 is composed of, for example, Cu.

[0039] The plurality of conductors 42 are provided inside the body portion 41 and are arranged side by side along the X direction and the Y direction. The plurality of conductors 42 extend inside the body portion 41 along the Z direction. The plurality of conductors are, for example, spring pins. The plurality of conductors 42 are in electrical and physical contact with the corresponding electrode portions 23 among the plurality of electrode portions 23. Each of the plurality of conductors 42 faces the second surface 26b of the corresponding bump 26 among the plurality of bumps 26 in the Z direction. Each of the plurality of conductors 42 is in electrical and physical contact with the second surface 26b of the corresponding bump 26 among the plurality of bumps 26.

[0040] The plurality of holding holes 43 extend along the Z direction. The plurality of holding holes 43 penetrate the body portion 41 in the Z direction. Each of the plurality of conductors 42 corresponding to each of the plurality of holding holes 43 is inserted therein.

[0041] The fixing member 50 fixes the flexible wiring board 2A to the main body 41 in a state where the flexible wiring board 2A is coupled to the connector 40A. The fixing member 50 is provided on the main surface 31a of the substrate main body 31 of the substrate member 3. The fixing member 50 has a first wall portion 51, a second wall portion 52, a pair of third wall portions 53 (see FIG. 1), and a fourth wall portion 54.

[0042] The first wall portion 51 and the second wall portion 52 are arranged along the X direction. The first wall portion 51 extends along the Y direction and the Z direction. The second wall portion 52 extends along the Y direction and the Z direction. An opening 52a is provided in the second wall portion 52. The base film 21 reaches the inside of the fixing member 50 through the opening 52a. The tip 24a of the tip portion 24 of the base film 21 contacts the main body 41 inside the fixing member 50. The pair of third wall portions 53 are arranged along the Y direction (see FIG. 1). Each of the pair of third wall portions 53 extends along the X direction and the Z direction. The fourth wall portion 54 faces the main surface 31a of the substrate main body 31 in the Z direction. The fourth wall portion 54 extends along the A direction and the Y direction.

[0043] The first wall portion 51, the second wall portion 52, and the pair of third wall portions 53 are fixed to the main surface 31a of the substrate main body 31 of the substrate member 3 and are arranged so as to surround the tip portion 24 of the base film 21 and the main body 41. The main body 41 is fixed to the main surface 31a. The fourth wall portion is arranged on the side opposite to the main body 41 with respect to the tip portion 24 of the base film 21. The fourth wall portion is integrally formed with the first wall portion 51, the second wall portion 52, and the pair of third wall portions 53. In this way, the fixing member 50 fixes the tip portion 24 of the base film 21 to the main body 41.

[0044] The tip 24a of the tip portion 24 of the base film 21 contacts the main body portion 41 of the connector 40A. Each bump 26 of the plurality of electrode portions 23 contacts each of the plurality of conductors 42. The base film 21 contacts the inner surfaces (not shown) of the pair of third wall portions 53 and the inner surface 54a of the fourth wall portion 54. Thus, the flexible wiring board 2A is held by the main body portion 41, the plurality of conductors 42, and the fixing member 50.

[0045] The connector (second connector) 40B has a main body portion 41, a plurality of conductors (a plurality of second conductors) 42, a plurality of holding holes 43, and a fixing member 50, similar to the connector 40A. The connector 40B is positioned between the main surface 21a of the base film 21 of the flexible wiring board 2A and the main surface 31a of the substrate body 31 of the substrate member 3. The connector 40B has a first end portion 40a and a second end portion 40b arranged along the X direction. The second end portion 40b is located on the side opposite to the connector 40A with respect to the first end portion 40a. The distance H1 between the main surface 21a and the main surface 31a is more than one time as large as the length H2 along the X direction of the connector 40B at the first end portion 40a.

[0046] In the connection structure 1 described above, the plurality of flexible printed circuit boards 2A and 2B are arranged side by side along the X direction. The flexible printed circuit board 2A is coupled to the connector 40A such that the A direction in which the main surface 21a extends intersects obliquely with respect to the X direction. The flexible printed circuit board 2B is coupled to the connector 40B such that the A direction in which the main surface 21a extends intersects obliquely with respect to the X direction. According to this connection structure 1, since the plurality of flexible printed circuit boards 2A and 2B extend in the A direction intersecting the X direction, interference between the plurality of flexible printed circuit boards 2A and 2B when arranged along the X direction is suppressed. Thereby, the plurality of flexible printed circuit boards 2A and 2B can be arranged at high density along the X direction. As a result, a plurality of wirings 22 can be arranged at high density not only in the Y direction but also in the X direction. For example, the number of channels in the connection structure 1 can be scaled. Further, in the connection structure 1 described above, each of the plurality of electrode portions 23 is electrically connected to the corresponding conductor 42 among the plurality of conductors 42 when the flexible printed circuit board 2A is coupled to the connector 40A. And each of the plurality of electrode portions 23 is electrically connected to the corresponding conductor 42 among the plurality of conductors 42 when the flexible printed circuit board 2B is coupled to the connector 40B. According to this connection structure 1, the wirings 22 in the plurality of flexible printed circuit boards 2A and 2B and the conductors 42 in the plurality of connectors 40A and 40B can be electrically connected with a simple structure. Thereby, deterioration of high-frequency characteristics in the connection structure 1 can be suppressed. From the above, while suppressing deterioration of high-frequency characteristics in the connection structure 1, a plurality of wirings 22 can be arranged at high density. In addition, since the plurality of flexible printed circuit boards 2A and 2B are respectively coupled to the plurality of connectors 40A and 40B such that the A direction intersects obliquely with respect to the X direction, the length of the connection structure 1 along the Z direction becomes small. Thereby, the connection structure 1 can be made lower-profile. For example, the connection structure 1 can be made lower-profile as compared with the case where the plurality of flexible printed circuit boards extend along the X direction and are arranged along the Z direction.

[0047] In the connection structure 1, the flexible printed circuit board 2A is coupled to the connector 40A such that the A direction in which the main surface 21a extends intersects the X direction in a range greater than 10 degrees and less than 80 degrees with respect to the X direction. In this case, when the A direction in which the main surface 21a extends intersects the X direction in a range greater than 10 degrees, it is possible to suppress the flexible printed circuit board 2A and the flexible printed circuit board 2B from contacting each other, so that the plurality of wirings 22 can be arranged in a higher density. Further, when the A direction in which the main surface 21a extends intersects the X direction in a range less than 80 degrees, the connection structure 1 can be sufficiently made low-profile.

[0048] In the connection structure 1, the inclination angle of the flexible printed circuit board 2B with respect to the X direction is in a range smaller than the inclination angle of the flexible printed circuit board 2A with respect to the X direction. In this case, it is possible to suppress the flexible printed circuit board 2A and the flexible printed circuit board 2B from interfering with each other. As a result, since the plurality of flexible printed circuit boards 2A and 2B can be arranged in a high density, the plurality of wirings 22 can be arranged in an even higher density.

[0049] In the connection structure 1, the connector 40A includes a main body portion 41 and a fixing member 50 that fixes the flexible printed circuit board 2A to the main body portion 41 in a state where the flexible printed circuit board 2A is coupled to the connector 40A. In this case, when the flexible printed circuit board 2A is coupled to the connector 40A, each of the plurality of electrode portions 23 can be stably electrically connected to the corresponding one of the plurality of conductors 42.

[0050] In the connection structure 1, the connector 40A includes a plurality of holding holes 43 that penetrate the main body portion 41 and into which the plurality of conductors 42 are respectively inserted. In this case, when the flexible printed circuit board 2A is coupled to the connector 40A, each of the plurality of electrode portions 23 can be more stably electrically connected to the corresponding one of the plurality of conductors 42.

[0051] In the connection structure 1, each of the plurality of electrode portions 23 includes an electrode pad 25 that is electrically connected to a corresponding one of the plurality of wirings 22, and a bump 26 provided on the electrode pad 25. In this case, the wiring 22 in the flexible wiring board 2A and the conductor 42 in the connector 40A can be electrically connected with a simpler structure. Thereby, the deterioration of the high-frequency characteristics in the connection structure 1 can be further suppressed.

[0052] In the connection structure 1, some of the plurality of electrode portions 23 are a plurality of electrode portions 23a arranged along the Y direction. Some of the other electrode portions 23 among the plurality of electrode portions 23 are a plurality of electrode portions 23b that are arranged along the Y direction and are located on the side opposite to the tip 24a of the tip portion 24 of the base film 21 with respect to the plurality of electrode portions 23a. The maximum value of the length along the B direction of the bump 26 included in each of the plurality of electrode portions 23b may be larger than the maximum value of the length along the B direction of the bump 26 included in each of the plurality of electrode portions 23a. In this case, when the flexible wiring board 2A is coupled to the connector 40A such that the A direction intersects obliquely with respect to the X direction, the plurality of electrode portions 23 can stably support the base film 21, and each of the plurality of electrode portions 23 can surely contact a corresponding one of the plurality of conductors 42. Thereby, each of the plurality of electrode portions 23 can be stably electrically connected to a corresponding one of the plurality of conductors 42.

[0053] In the connection structure 1, the bump 26 includes a first surface 26a that extends along the A direction and contacts a corresponding one of the plurality of electrode pads 25, and a second surface 26b that is located on the side opposite to the first surface 26a with respect to the bump 26 and extends along the X direction. The second surface 26b contacts a corresponding one of the plurality of conductors 42 when the flexible wiring board 2A is coupled to the connector 40A. In this case, the flexible wiring board 2A is stably supported by the connector 40A via the plurality of bumps 26. Thereby, each of the plurality of electrode portions 23 can be more stably electrically connected to a corresponding one of the plurality of conductors 42.

[0054] As described above in detail about the connection structure 1 according to the present disclosure, the present invention is not limited to the above-described embodiments, and can be applied to various embodiments and modifications.

[0055] FIG. 5 is a cross-sectional view showing a connection structure according to a modification. As shown in FIG. 5, each of the plurality of electrode portions 23 may have bumps 126 instead of bumps 26, and the connector 40A may have a plurality of conductors 142 instead of the plurality of conductors 42.

[0056] The bump 126 includes a first surface 126a and a second surface 126b. The first surface 126a extends along the A direction and the Y direction. The first surface 126a contacts the corresponding electrode pad 25 among the plurality of electrode pads 25. The second surface 126b is located on the side opposite to the first surface 126a with respect to the bump 126. The second surface 126b extends along the A direction and the Y direction. The maximum value of the length along the B direction of the bump 126 included in each of the plurality of electrode portions 23a is larger than the maximum value of the length along the B direction of the bump 126 included in each of the plurality of electrode portions 23b).

[0057] Each of the plurality of conductors (plurality of first conductors) 142 faces the second surface 126b of the corresponding bump 126 among the plurality of bumps 126 in the Z direction. Each of the plurality of conductors 142 is in electrical and physical contact with the corresponding bump 126 among the plurality of bumps 126 when the flexible wiring board 2A is coupled to the connector 40A.

[0058] In such a case, the flexible wiring board 2A is stably supported by the connector 40A via the plurality of bumps 126. Thereby, each of the plurality of electrode portions 23 can be more stably electrically connected to the corresponding conductor 42 among the plurality of conductors 42.

Description of Reference Numerals

[0059] 1... Connection structure 2A... Flexible wiring board (first flexible wiring board) 2B… Flexible Printed Circuit Board (Second Flexible Printed Circuit Board) 3… Substrate Member 21… Base Film (First Base Film) (Second Base Film) 21a… Main Surface (First Main Surface) (Second Main Surface) 22… Wiring (First Wiring) (Second Wiring) 23… Electrode Portion (First Electrode Portion) (Second Electrode Portion) 23a… Electrode Portion (Third Electrode Portion) 23b… Electrode Portion (Fourth Electrode Portion) 24… Tip Portion 24a… Tip 25… Electrode Pad 26… Bump 26a… First Surface 26b… Second Surface 31a… Main Surface (Third Main Surface) 40A… Connector (First Connector) 40a… First End 40b… Second End 40B… Connector (Second Connector) 41… Body Portion 42… Conductor (First Conductor) (Second Conductor) 43… Holding Hole 50… Fixing Member 51… First Wall Portion 52… Second Wall Portion 52a… Opening 53… Third Wall Portion 54… Fourth Wall Portion 54a… Inner Surface 126… Bump 126a… First Surface 126b… Second Surface 142… Conductor (First Conductor) (Second Conductor) H1… Distance H2… Length L… Length

Claims

1. A first flexible printed circuit board including a first base film having a first main surface extending along a first direction, a plurality of first wirings provided in or on the first base film, and a plurality of first electrode portions provided on the first main surface at a tip portion of the first base film in the first direction and electrically connected to corresponding first wirings among the plurality of first wirings, A second flexible printed circuit board including a second base film having a second main surface extending along the first direction, a plurality of second wirings provided in or on the second base film, and a plurality of second electrode portions provided on the second main surface at a tip portion of the second base film in the first direction and electrically connected to corresponding second wirings among the plurality of second wirings, and being arranged side by side with the first flexible printed circuit board along a second direction, A substrate member including a substrate body extending along the second direction and having a third main surface facing the first main surface and the second main surface, a first connector provided on the third main surface and including a plurality of first conductors, and a second connector provided on the third main surface and including a plurality of second conductors, and the first connector and the second connector being arranged side by side along the second direction, Comprising, The first flexible printed circuit board is coupled to the first connector such that the first direction in which the first main surface extends intersects obliquely with the second direction, The second flexible printed circuit board is coupled to the second connector such that the first direction in which the second main surface extends intersects obliquely with the second direction, Each of the plurality of first electrode portions is electrically connected to a corresponding first conductor among the plurality of first conductors when the first flexible printed circuit board is coupled to the first connector, Each of the plurality of second electrode portions is electrically connected to a corresponding second conductor among the plurality of second conductors when the second flexible printed circuit board is coupled to the second connector. A connection structure.

2. The inclination angle of the second flexible printed circuit board with respect to the second direction is in a range smaller than the inclination angle of the first flexible printed circuit board with respect to the second direction. The connection structure according to claim 1.

3. The first connector further includes a main body portion and a fixing member that fixes the first flexible printed circuit board to the main body portion in a state where the first flexible printed circuit board is coupled to the first connector. The connection structure according to claim 1 or claim 2.

4. The first connector further includes a plurality of holding holes that penetrate the main body portion and into which the plurality of first conductors are respectively inserted. The connection structure according to claim 3.

5. The second connector is positioned between the first main surface of the first base film of the first flexible printed circuit board and the third main surface of the substrate body of the substrate member. The second connector further includes a first end portion and a second end portion that are arranged along the second direction. The second end portion is located on the side opposite to the first connector with respect to the first end portion. The distance between the first main surface and the third main surface is more than one time the length of the second connector along the second direction at the first end portion. The connection structure according to claim 1 or claim 2.

6. Each of the plurality of first electrode portions includes an electrode pad that is electrically connected to a corresponding first wiring among the plurality of first wirings, and a bump provided on the electrode pad. The connection structure according to claim 1 or claim 2.

7. Some of the plurality of first electrode portions are a plurality of third electrode portions arranged along a third direction that intersects the first direction and the second direction. Among the plurality of first electrode portions, some other first electrode portions are a plurality of fourth electrode portions that are arranged along the third direction and are located on the side opposite to the tip of the tip portion of the base film with respect to the plurality of third electrode portions. The maximum value of the length along the fourth direction perpendicular to the first main surface of the bump included in each of the plurality of fourth electrode portions is larger than the maximum value of the length along the fourth direction of the bump included in each of the plurality of third electrode portions. The connection structure according to claim 6.

8. The bump includes a first surface that extends along the first direction and contacts the electrode pad, and a second surface that is located on the side opposite to the first surface with respect to the bump and extends along the second direction. When the first flexible wiring board is coupled to the first connector, the second surface contacts a corresponding first conductor among the plurality of first conductors. The connection structure according to claim 6.

9. The bump includes a first surface that extends along the first direction and contacts the electrode pad, and a second surface that is located on the side opposite to the first surface with respect to the bump and extends along the first direction. When the first flexible wiring board is coupled to the first connector, the second surface contacts a corresponding first conductor among the plurality of first conductors. The connection structure according to claim 6.

10. A flexible wiring board that can be coupled to a substrate member including a substrate body, A base film having a main surface that extends obliquely intersecting the direction in which the substrate body extends, A plurality of wirings provided in or on the base film, A plurality of electrode portions provided on the main surface at the tip portion of the base film in the extending direction and electrically connected to corresponding wirings among the plurality of wirings respectively. A flexible wiring board comprising:

11. A base film having a main surface, a plurality of wirings provided in or on the base film, and a plurality of electrode portions provided on the main surface at the tip of the base film and electrically connected to corresponding wirings among the plurality of wirings, Each of the plurality of electrode portions has a surface located on the side opposite to the base film, and the surface is inclined with respect to the main surface, a flexible printed circuit board.

12. A substrate member that can be coupled to a plurality of flexible printed circuit boards each including a base film having a first main surface extending along a first direction and a plurality of electrode portions provided on the first main surface, a substrate body having a third main surface extending along a second direction that intersects obliquely with respect to the first direction, a plurality of connectors arranged along the second direction on the third main surface and each including a plurality of conductors, and, the plurality of conductors are electrically connected to corresponding electrode portions among the plurality of electrode portions when the connector is coupled to the flexible printed circuit board, a substrate member.

13. The connector further has a main body portion and a fixing member that fixes the flexible printed circuit board to the main body portion in a state where the flexible printed circuit board is coupled to the connector, The substrate member according to claim 12.

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