JPH0758430A - Connection structure of board - Google Patents

Abstract

PURPOSE:To provide a structure of connecting a board to a board perpendicular thereto without forming patterns on a side of the board. CONSTITUTION:In a board 1 on which an optical part 5 is mounted, a surface layer pattern 6 connecting to a board 2 arranged vertically is connected to a rear surface pattern 7 by a through hole 8 or a via, etc., and a metal frame 3 is secured to the rear surface pattern 7 by a method of soldering, brazing, thermocompressing, etc. After the boards 1, 2 are fixed to a case 4, etc., the metal frame 3 is connected to an optical circuit pattern 9 on the board 2 by thermocompressing. With this structure, patterns on a side of the board are unneeded and also the entire shape can be thinned.

Description

Detailed Description of the Invention

The present invention relates to a board connecting structure, and more particularly to a board connecting structure for an optical interface.

[0002]

2. Description of the Related Art Conventionally, a connection structure of an optical interface substrate on which an optical component is mounted so as to face an optical fiber or the like is shown in FIG. Board 11
An optical component 15 for receiving light such as an optical fiber coming in from the direction of arrow A is mounted on the board, and the shape of the substrate 11 is relatively small. On the other hand, there is a relatively large-sized substrate 12 on which electronic components and circuit patterns required for this optical interface are mounted. When mounting these substrates 11 and 12 to be connected to each other, at least the substrate 12 cannot be arranged on the A direction side of the substrate 11 on which light is incident. Therefore, the arrangement condition of the substrate 11 which is incident on the substrate surface perpendicularly and the substrate 12 for the interface thereof, when considering the relationship of the difference in size between the two substrates, as shown in FIG. Is case 1
4 are arranged at right angles to each other and the substrate 12 is the substrate 11
It is generally provided on the side opposite to the light incident direction. The substrate 11 has a surface layer pattern 16 on the mounting surface of the optical component 15.
, And the side surface pattern 17 is provided on the side surface orthogonal to the surface, while the board 12 is arranged such that the surface on which the electronic parts and the circuit pattern are mounted is substantially the same height as the side surface of the board 11. Cage, side pattern 17 and substrate 1
The circuit pattern on the upper part 2 is connected by the bonding wire 13.

[0003]

This conventional board connection structure requires a side surface pattern to serve as a pad for wire bonding in a board on which optical components are mounted, so that the board manufacturing process is complicated. . Also, in the process of manufacturing the board, the surface layer pattern must be printed on the optical component mounting surface, and after cutting to the specified dimensions, the wire bonding pattern must be printed on the side surface, so a sharp surface is required on the side surface. There was a problem that was done. Further, from the viewpoint of workability of wire bonding, since the side surface pattern of one substrate and the mounting surface of the electronic component and the circuit pattern of the other substrate have almost the same height, only the electronic component can be mounted from the mounting surface. There is a drawback that the shape becomes protruding and the overall size in the height direction is increased by the height of the electronic component.

[0004]

According to the present invention, in a board connecting structure in which two boards are assembled at right angles and wired, an arbitrary pattern of one board is connected to a back surface pattern by a through hole or a via, In this structure, a conductive metal frame is fixed to the back surface pattern, and the metal frame is pressure-bonded to the other substrate for electrical connection.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of the present invention, (a) is a front view,
(B) is a perspective view.

In this embodiment, a substrate 1 on which an optical component 5 is mounted, a circuit pattern 9 and an electronic component 1 are mounted on a case 4.
The substrate 2 on which 0 is mounted is arranged at right angles to each other, and electrically connected by the conductive metal frame 3.

The substrate 1 is a relatively small substrate on which the optical component 5 is mounted, and has a surface layer pattern 6 on the mounting surface of the optical component 5 for connecting a signal from the optical component 5 or the like to the substrate 2. Through hole 8 penetrating pattern 6 through substrate 1
(Or via) to connect to the backside pattern 7. Light from an optical fiber or the like enters the substrate 1 from the direction of arrow A into the optical component 5 substantially perpendicular to the substrate surface.
Further, the height dimension of the substrate 1 is preferably equal to or less than [thickness of the substrate 2 + height of an electronic component 10 (described later) on the substrate 2]. On the other hand, the dimension of the substrate 1 in the longitudinal direction is inevitably long when the circuits are in a parallel system, and the length is not particularly limited.

After mounting the optical component 5 and the like on such a substrate 1, the conductive metal frame 3 is fixed to the back surface pattern 7 by a method such as soldering, brazing or pressure bonding. The metal frame 3 has a substantially linear rod shape and supplies different potentials between the substrates 1 and 2, so that each metal frame 3 has a separate shape so as not to short-circuit with another. Further, the metal frame 3 has elasticity enough to absorb the dimensional tolerance of the printing of the back surface pattern 7 and the circuit pattern 9 and the tolerance of the adhesion of the substrates 1 and 2 to the case 4, and thus has a thin plate shape. Alternatively, it is made of a material such as wire. In order to fix the metal foil 3 to the back surface pattern 7, soldering or brazing can be performed before mounting the optical component 5 on the substrate 1, but after mounting the optical component 5, crimping is performed. Is the best.

Next, the substrates 1 and 2 are fixed to the case 4 with silver paste, and the required metal frame 3 from the back surface pattern 7 of the substrate 1 is pressure-bonded to an appropriate portion of the circuit pattern 9 on the substrate 2. This completes the electrical connection between the substrates 1 and 2. In addition, the pressure bonding of the metal frame 3 to the substrate 2 is
The components on the substrate 1 are the optical components 5, and the substrates 1, 2
Since it is fixed and integrated with the case 4, soldering or adhesion with a conductive paste is not preferable for protection of the optical component 5, and pressure bonding is preferable. Regarding the height relationship between the substrate 1 and the substrate 2, the shape of the case 4 is designed so that the height position of the fixing pad of the metal frame 3 on the substrate 1 and the height of the upper surface of the substrate 2 are matched.
The height difference due to the dimensional tolerance may be absorbed by the elasticity of the metal frame 3. In addition, both boards 1, 2
The electronic component 1 to be mounted on the upper surface of the substrate 2 when designing the height of
By taking care so that the maximum height portion of 0 (H in FIG. 1A) does not exceed the height of the substrate 1, the overall height dimension can be reduced and the thickness can be reduced.

Regarding the silver paste for fixing the substrates 1 and 2 to the case 4, if it is necessary to supply a potential to the case 4, a conductive paste such as silver paste or a conductive film adhesive is used. If it is not necessary to supply a potential, an insulating paste may be used.

In the present embodiment, the metal frame 3 is illustrated as an elastic substantially straight rod shape, but the present invention is not limited to this, and as long as the metal frame 3 has elasticity, it has an arc shape or an L shape. Needless to say, the shape may be freely changed according to the mounting conditions of the substrates 1 and 2.

[0012]

As described above, according to the present invention, in two substrates arranged at right angles to each other for an optical interface, an arbitrary pattern of one substrate is connected to a back surface pattern by a through hole or a via, and the back surface is connected. The following effects are obtained by the structure in which the conductive metal frame is fixed to the pattern by a method such as soldering, brazing, or pressure bonding, and the metal frame is pressure-bonded to the other substrate.

(1) The patterning of the side surface of the substrate becomes unnecessary, and the complexity of the substrate manufacturing process is alleviated.

(2) Due to the elasticity of the metal frame, connections can be made regardless of the difference in the heights of the upper surfaces of the two boards, and the board is designed to be lowered by the height of the electronic parts. The overall thickness can be reduced.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, (a) is a front view,
(B) is a perspective view.

FIG. 2 is a perspective view showing an example of a conventional board connection structure.

[Explanation of symbols]

 1,2,11,12 Substrate 3 Metal frame 4,14 Case 5,15 Optical component 6,16 Surface layer pattern 7,17 Side pattern 8 Through hole 9 Circuit pattern 10 Electronic component 13 Bonding wire

Claims (3)

[Claims] 1. In a board connection structure in which two boards are assembled at right angles and wired, an arbitrary pattern on one board is connected to a back surface pattern by a through hole or a via, and a conductive metal is formed on the back surface pattern. A substrate connection structure, characterized in that a frame is fixed and the metal frame is pressure-bonded to the other substrate for electrical connection. 2. The substrate according to claim 1, wherein the one substrate is provided with an optical element that receives light incident from a direction perpendicular to the substrate surface and in a direction opposite to the other substrate. Connection structure. 3. The substrate connecting structure according to claim 1, wherein the metal frame has elasticity.