JPH0427195Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a technology for packaging electronic circuits in high density.

[Summary of the idea]

When mounting an electronic circuit on a printed circuit board, this idea standardizes the size of the sub-board, supports it on the motherboard with a predetermined support frame, and connects it electrically. This achieved higher density.

[Conventional technology]

As video cameras and VTRs become smaller, electronic circuits are required to be mounted in higher density. As a technique for such high-density packaging, there is a method shown in FIGS. 4 and 5.

That is, in these figures, 10 indicates a sub-board (auxiliary printed circuit board), and this sub-board 10 has an IC 11, a relatively low general component 12, and a chip component 1 on both sides.
3 etc. are soldered, and a lead pin 14 having an F-shaped cross section is attached to the side of the board 10.
are soldered in a dual inline manner.

Then, such a board 10 is attached to a main board (main printed circuit board) 20. In this case, the sub-board 10 is attached to the main board 20 by inserting the pins 14 into through-holes of the main board 20 and soldering them, like a general IC. Further, general parts 22 and chip parts 23 are soldered to both sides of the main board 20.

Further, as another method of high-density packaging, there is a technique shown in FIGS. 6 and 7.

That is, the board 10 and the elements 11 to 14 are the same as in the above example, but the tip of the pin 14 is bent outward, and the tip is soldered to the conductor pattern of the motherboard 20 and attached.

[Problem that the invention attempts to solve]

However, in the mounting method shown in FIGS. 4 and 5, a through hole is required in the main board 20 in order to attach the sub board 10 to the main board 20, but in order to form the through hole, a through hole is required in the mother board 20. requires a land with a diameter of about 0.8 mm, which is a size that cannot be ignored for high-density mounting. Further, processing of the through hole is also required, which increases the cost.

Furthermore, in the implementation method shown in FIGS. 6 and 7,
An area corresponding to the tips (bent portions) of the pins 14 is required on the motherboard 20, which cannot be ignored for high-density mounting.

Furthermore, in either mounting method, since the pins 14 are soldered to the sub-board 10, components cannot be mounted within the area A from the side thereof, which is also disadvantageous for high-density mounting.

Furthermore, in either mounting method, the pin 14 must be soldered to the sub-board 10 and the motherboard 20. In other words, one pin 14 requires soldering in two places, so it is difficult to assemble the pin 14. This results in an increase in man-hours. In addition, as shown in FIG.
0, a wasted space is created above the sub-board 10, which is also not preferable for high-density mounting.

This idea is an attempt to eliminate the above problems.

[Means for solving problems]

Therefore, in this invention, the size of the sub-boards is standardized, they are attached to the motherboard using a predetermined support frame, and electrical connections between each board are made through bus lines provided on the support frame. This is how it was done.

[Effect]

Since subboards can be multilayered and lead pins between each subboard and the motherboard are no longer necessary, extremely high-density packaging is possible.

〔Example〕

In FIG. 1, the sub-board 10 is formed into a rectangular shape by a multilayer through-hole board, a small capacitor is formed by a conductive pattern and a ceramic layer interposed therebetween, and a resistor is formed by a printed resistor. , each element is electrically connected by a conductor pattern and a through hole. Also, IC11 and other mounting parts 12,1
3 are soldered to both sides of the board 10. Further, on two parallel sides of the board 10, for example, semicircular guide notches 1 are provided at predetermined intervals.
5 is formed, and the terminal 1 is inserted into this notch 15.
6 is formed by through-hole plating, and necessary ones of the conductor patterns on the board 10 are connected to this terminal 16.

Further, the other sub-boards 10 are also standardized to the same size and configured similarly.

Further, the support frame 30 is configured as shown in FIG. 2, for example. That is, the frame 30 is constructed of a main body 31 and its lid 32 to a size corresponding to the sub-board 10, and the main body 31 is made of an insulating material such as synthetic resin and has a U-shape as a whole. At the same time, a plurality of pairs of guide grooves 31A and 31B into which the sub-board 10 is slidably inserted are formed on the inner walls of the pair of parallel legs. Further, a guide groove 31 is provided on the inner wall of the central portion of the main body 31.
A plurality of bus lines 33 are connected to terminals 16 by conductive wires having elasticity in a direction perpendicular to the plane including A and 31B.
This bus line 3 is provided at intervals of
3 is taken out as a terminal 34 at the end (bottom) of the main body 31. In this case, the bus line 33 is convex inward at positions corresponding to the guide grooves 31A and 31B.

Furthermore, a bus line 33 is provided on the inner wall of the lid body 32.
A bus line 33 similar to that is provided, and
The end portion is taken out as a terminal 34.

Also, 35 is a shield case, which is the main body 3
1 and the lid body 32 are combined into a cap shape that covers them.

The plurality of sub-boards 10 on which the respective components are mounted are guided by the guide grooves 31A and 31B and supported within the main body 31, and the lid body 32 is disposed in the opening direction of the legs of the main body 31. They are integrated as a support frame 30, and a shield case 35 is placed over the support frame 30 from the side opposite to the terminals 34. Therefore, in this state, since the terminals 16 of the sub-boards 10 are in contact with the bus lines 33, the plurality of sub-boards 10 are connected to the bus lines 33 through the terminals 16.
will be connected to each other through

Then, a desired electronic circuit is constructed by soldering the terminals 34 to the motherboard 20.

Thus, according to this invention, an electronic circuit is implemented, and in this case, in particular, according to this invention:
Since it is not necessary to provide lead pins 14 on the sub-board 10, the packaging density of the sub-board 10 can be increased, and the packaging scale can be increased. For example, in the past, the mounting density and number of parts for one sub-board 10 was 3 to 5 pieces/cm ²
According to this invention, the number of sub-boards can be 15/20 pieces/cm ² and 100-200 points, and each sub-board can have a function.

Furthermore, since a plurality of sub-boards 10 can be stacked in multiple layers, the heights can be made the same as those of other large components 22 mounted on the motherboard 20, and from this point of view as well, the mounting density is improved.

Furthermore, since each component is arranged three-dimensionally, the length of the wiring for each component can be shortened, and the characteristics can therefore be improved. Furthermore, during repair, ten sub-boards can be replaced in units, which improves work efficiency. Additionally, devices equipped with this electronic circuit can be made smaller and lighter. Furthermore, the number of soldering points is reduced, which improves productivity.

In the example shown in FIG. 3, the main body 31 and the lid 3
2 are integrated to form a frame 30, and a plurality of sub-boards 10 are inserted alternately with spacers (not shown) from the opening of the frame 30.

Note that in the above description, a shield plate may be interposed between the two sub-boards 10.

[Effect of idea]

According to this invention, since it is not necessary to provide lead pins 14 on the sub-board 10, the packaging density of the sub-board 10 can be increased, and the packaging scale can be increased. For example, the packaging density and number of parts for one sub-board 10 is conventionally 3 to 5 pieces/cm ² and 20 to 50 parts, but according to this invention, it is 15/20 pieces/cm ² and 20 to 50 parts.
It can be set to 100 to 200 points, and each sub-board can have functions in units of 10.

Furthermore, since a plurality of sub-boards 10 can be stacked in multiple layers, the heights can be made the same as those of other large components 22 mounted on the motherboard 20, and from this point of view as well, the mounting density is improved.

[Brief explanation of the drawing]

FIGS. 1 to 3 are perspective views of an example of this invention, and FIGS. 4 to 7 are illustrations for explaining the same. 10 is a subboard, 11 to 13, 22, and 23 are mounting components, 20 is a motherboard, and 30 is a support frame.

Claims (1)

[Claim for Utility Model Registration] It has a sub-board formed of a multilayer through-hole board, a support frame, and a motherboard, the sub-board has a standardized size, and the sub-board has an IC or chip. Components and the like are mounted, terminals connected to elements provided on the sub-board are provided on the side of the sub-board, and the support frame is sized to correspond to the sub-board. A bus line is provided at a predetermined position on the inner wall of the support frame, the support frame is mounted on the motherboard, and the support frame supports the plurality of sub-boards in a multilayer structure, A printed circuit board, wherein the sub-board is electrically connected to the sub-board or the motherboard through the terminals and the bus line.