JPS63301587A - Board connection structure - Google Patents

Abstract

PURPOSE:To facilitate connection in a small area by a method wherein a 1st board has wiring conductors on its 1st surface and a 2nd board has wiring conductors on both of 1st and 2nd surfaces and overlapping regions are provided at the end parts of both the board. CONSTITUTION:Every other conductors 2a among wiring conductors 2 of a 1st board 1 exist in an overlapping region 7 where the 1st board 1 and 2nd board 5 overlap each other. The wiring conductors 2a are bonded to the wiring conductors 4a of the 1st surface 5a of the 2nd board 5 with anisotropic conductive adhesive or the like. On the other hand, conductors 2b existing between every other conductors 2a are connected to the wiring conductors 4b of the 2nd surface of the 2nd board 5 with a tape connector 8. With this structure, the number of wiring conductors mutually connected in the overlapping region 7 is approximately 1/2 of the total number of the wiring conductors on the 1st board. Therefore, if a distance between the adjacent conductors when the conductors are brought into contact with each other for mutual connection in the overlapping region 7 is the same as the distance with the conventional constitution, the pitch between the wiring conductors is 1/2 of the pitch with the conventional constitution and the width of the overlapping region can be halved. With this constitution, an area required for the connection can be redused.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a connection structure between boards in electronic equipment.

1 [Prior Art] FIG. 2 is a perspective view showing an example of a conventional connection structure. The wiring 4 of the flexible substrate 5 is formed with wiring 4 having the same width and pitch as the external wiring connection terminal 3 on the substrate 1, which is the base of the external connection part of various electronic devices, and the wiring 4 is placed over the connection terminal 3. They were matched together and connected using methods such as soldering or pressure welding.

[Problems that the invention attempts to solve]

However, in recent years, electronic devices have become smaller and more densely packed, and the connection pitch and connection area have become extremely small. Therefore, the connection configuration described above has problems such as the area required for connection (connection area) being relatively large and alignment becoming difficult as the pitch is reduced.

The present invention eliminates the above-mentioned problems that the area for connection becomes large and alignment is difficult at minute pitches, and provides a connection structure that allows connections to be made in a small area and is highly reliable. The purpose is to provide.

[Means for solving problems]

The substrate connection structure of the present invention includes a first substrate having a wiring conductor on a first surface, a second substrate having wiring conductors on the first and second surfaces, and a wiring conductor on the first substrate. and the second above
connecting means for connecting the wiring conductor on the substrate, the first substrate and the second substrate have overlapping regions near their respective ends, and the first substrate and the second substrate have overlapping regions overlapped with each other, and
The wiring conductors of the board are parallel to each other near the pattern area, every other wiring conductor extends into the pattern area, and the other wiring conductors have ends near the pattern area. Among the wiring conductors on the first surface of the second substrate, those located within the pattern area extend parallel to each other, and each of the wiring conductors on the first surface of the first substrate is arranged in the pattern area. Among the wiring conductors on the second surface of the second substrate, those located within the molded area are parallel to each other, and among the wiring conductors on the first surface, extending parallel to those located in the overlap region, the connecting means comprising a tape connector having wiring conductors parallel to each other, the wiring conductors of the tape connector having one end in the color of the first substrate. The other end is connected to the wiring on the second surface of the substrate $2.

[11] In the above configuration, only every other wiring conductor of the first board exists in the overlapping area where the first board and the second board overlap, and this is the wiring conductor of the second board. It is bonded to the wiring conductor on the first surface of the substrate using an anisotropic conductive adhesive or the like. on the other hand,
The conductors located between every other wiring conductor (“other wiring conductors”) are connected to the wiring conductors on the second surface of the second board by tape connectors. Therefore, the number of wiring conductors connected to each other within the overlapping region is approximately 1/2 of the total number of wiring conductors on the first substrate. Therefore, if the distance between adjacent conductors when making a connection by contacting each other within the overlap area is the same as before, the pitch of the wiring conductors outside the overlap area will be the conventional 172, and the width of the overlap area (
The dimension in the direction perpendicular to the direction in which the wiring conductor extends) is 172
It can be done. Therefore, the area required for connection is also significantly reduced.

[Example 1 FIG. 1 and FIGS. 3 to 5 show an example of the present invention. Of these, FIG. 1 shows the connection state,
3 to 5 show each board and tape connector before connection. As shown in the figure, this connection structure includes a substrate 1 on which electronic components (not shown) such as a thermal head are mounted and whose leads are connected to an external connection wiring conductor 2, and an external electronic circuit such as a drive circuit for the thermal head. This is a lug for connecting to a flexible substrate 5 having wiring conductors 4a and 4b for connection to the flexible substrate 5.

The wiring conductor 2 of the substrate 1 is provided on the first surface (the upward surface in the drawing) la of the substrate 1. Flexible board 5
The wiring conductor i4a is provided on the first surface (downward surface in the drawing) 5a of the flexible substrate 5, and the wiring conductor 4b is provided on the second surface (upward surface in the drawing) 5a of the flexible substrate 5.
b. That is, the wiring conductors 4a and 4b are arranged in a staggered manner in a longitudinal cross-sectional shape perpendicular to the extending direction of these conductors.

The substrate 1 and the substrate 5 have overlapping regions 7 near their respective end portions IC and 5C, where they are overlapped with each other. As shown in FIG. 3, the wiring conductors of the board 1 are parallel at least in the vicinity of this overlapping region, and every other wiring conductor #2a extends within the overlapping region 7 and reaches the end IC. ing. On the other hand, the other wiring conductor (wiring conductor interposed between every other wiring conductor) 2b has an end near the overlapping region 7. The wiring conductors 4a on the first surface 5a of the flexible substrate 5 also extend parallel to each other at least within the overlapping region 7.

Each of these wiring conductors 4a is connected to each of the wiring conductors 2a in the overlapping region 7 among the wiring conductors of the first substrate 1. This connection is made using the wiring conductor 4 of the flexible board 5.
This is done by applying an anisotropically conductive adhesive 9C on the substrate a and heat-pressing it to the first substrate 1. The wiring conductors 4b on the second surface 5b of the flexible substrate 5 also extend parallel to each other and parallel to the wiring conductors on the first surface 5a at least in the overlapping region 7. The tape connector 8 is connected to the wiring conductor 2b of the board 1. The tape connector 8 has wiring conductors 11 parallel to each other on one side of a synthetic resin film 10, with one end 11a
is connected to the wiring 2b of the substrate 1, and the other end 11b is connected to the wiring conductor on the second surface 5b of the substrate 5. Anisotropically conductive adhesives 9a and 9b are used for connection.

Wiring conductors 2a, 2 near the overlapping region 7 of the substrate 1
b, the pitch of the wiring conductors 2a in the overlapping region 7 of the substrate 1, and the wiring conductors 4a on each of the surfaces 5a, 5b of the substrate 5.

4b pitch and the wiring conductor 11 of the tape connector 8
The pitch of is twice as large.

In assembling the above connection structure, first align the wiring conductor 4a of the board 5 with the wiring conductor 2a of the board 1, and then use the anisotropic conductive adhesive 9c to connect the wiring conductor 2a and the wiring conductor 4a.
and to each other.

Next, the anisotropic conductive adhesives 9a and 9b are applied to the tape connector 8.
(both ends 11a, 11b of the wiring conductor), and anisotropic conductive adhesives 9a, 9b are applied to the parts.
The wiring conductors 2b of the substrate 1 and the wiring conductors 4b of the flexible substrate 5 are respectively arranged to face each other, and the wiring conductors are aligned with each other and connected by heat pressure welding. In this way, the anisotropically conductive adhesive exhibits conductivity only in the thickness direction where pressure is applied.

In the above embodiment, the substrate 1 is for mounting electronic components, and the substrate 5 is for wiring, but the present invention can be applied to substrates for any purpose.

〔Effect of the invention〕

As described above, according to the present invention, the area required for connection can be reduced, and positioning during assembly can be facilitated.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a connection structure according to an embodiment of the present invention, FIG. 2 is a perspective view showing a conventional connection structure, FIG. 3 is a perspective view showing a part of a board on which electronic components are mounted, and FIG. The figure is a perspective view showing a part of a flexible board for wiring coated with an anisotropic conductive adhesive, and FIG. 5 is a perspective view showing a tape connector. 1... Substrate, 2.2a, 2b, 4a, 4b. 11... Wiring conductor, 5... Flexible board, 7
...overlapping area, 8...tape connector, 9a. 9b, 9c...Anisotropic conductive adhesive. Patent Applicant: Oki Electric Industry Co., Ltd. Agent, Patent Attorney (former) 1) Real 2a wiring board base (for mounting electronic components) Figure 3 Flexible 7 bull board 9a adhesive tape Coil/lid Figure 5

Claims (1)

[Scope of Claims] A first substrate having a wiring conductor on a first surface, a second substrate having wiring conductors on first and second surfaces, a wiring conductor on the first substrate and the above-mentioned wiring conductor. a connecting means for connecting the wiring conductor on the second substrate, the first substrate and the second substrate having an overlapping region near their respective ends to be overlapped with each other; The wiring conductors of the board are parallel to each other near the overlapping region, every other wiring conductor extends into the overlapping region, and the other wiring conductors have ends near the overlapping region, and the second wiring conductor has an end near the overlapping region. Of the wiring conductors on the first surface of the substrate, those located within the overlapping region extend parallel to each other,
Each of them is bonded to each of the wiring conductors on the first substrate within the overlapping region, and among the wiring conductors on the second surface of the second substrate located within the overlapping region, the wiring conductors on the second surface of the second substrate are bonded to each other. parallel to and extending parallel to those of the wiring conductors of the first surface located in the overlapping region, the connecting means comprising a tape connector having wiring conductors parallel to each other; One end of the wiring conductor is connected to the vicinity of the end of the other wiring on the first board, and the other end is connected to the wiring on the second surface of the second board. Board connection structure. 2. The structure according to claim 1, wherein the tape connector is bonded to the first substrate and the second substrate with an anisotropic conductive adhesive. 3. The structure according to claim 1, wherein the second substrate is bonded to the first substrate with an anisotropic conductive adhesive.