JPH01282894A - Mounting structure of circuit parts - Google Patents

Abstract

PURPOSE:To highly densely mount large-sized circuit parts and small-sized circuit parts different in height and dimensions in a housing without waste of space by preventing the production of a wasteful mounting space on the mounting side of the large-sized circuit parts by projections and recesses provided on a resin mold wiring board. CONSTITUTION:A resin mold wiring board 13 has a flexible wiring board 14 in which a circuit pattern is formed on both the faces thereof and a resin board 15 in which the substrate 14 is integratedly molded and formed on a face side of the substrate 14. Large-sized circuit parts 16-18 different in height and dimensions are mounted on the surface of the board 15 side of the board 13. Projections and recesses are provided on the surface of the board 15 side of the board 13 and the other surface of the board 14 in accordance with the difference of height and dimensions of the parts 16-18 so that the height of the top part of parts 16-18 is arranged properly. Small-sized circuit parts 19, 20 are mounted in a recess area 14a of the board 14 of the rear side of an area 15a. Thereby the parts 16-20 are highly densely mounted in a housing without waste of space.

Description

[Detailed Description of the Invention] [Summary] Functional components with different height dimensions on wiring boards that are divided vertically inside the housing, large circuit components such as functional monocalls, and small-sized circuit components such as lead components, volume IJ, -m, etc. Regarding the mounting structure of circuit components, circuit components including large circuit components and small circuit components such as functional components and functional modules with different height dimensions are mounted spatially at high density within a small housing. The purpose of the present invention is to provide a mounting structure for circuit components that can easily automate the mounting work. A resin molded wiring board having a flexible wiring board and a resin board integrally molded on one side, large circuit components having different height dimensions mounted on the resin board side surface of the resin molded wiring board, and In order to ensure that the heights of the tops of large circuit components are almost the same, unevenness is provided on the resin board side surface of the resin molded wiring board and the flexible wiring board side surface according to the difference in height dimension of the large circuit components. The small circuit component is mounted in the concave region of the flexible wiring board located on the back side of the region where the large circuit component mounting surface side is raised in a convex shape.

[Industrial application field]

The present invention relates to a circuit component mounting structure in which large circuit components such as functional components and functional modules with different height dimensions and small circuit components such as lead components and volumes are mounted on wiring boards that are divided vertically within a housing. In particular, the present invention relates to a circuit component mounting structure using a resin molded wiring board having a flexible wiring board and a resin substrate integrally molded with the flexible wiring board on one side of the flexible wiring board.

Radio waves in the quasi-microwave band (around IGHz) are beginning to be used in mobile communication devices, such as car phones, mobile phones, cordless phones, etc. High-frequency circuits of mobile communication devices that use radio waves in the quasi-microwave band such as these This is difficult to achieve with a circuit configuration method that combines lumped constant components such as resistors, capacitors, coils, etc., and there are many parts that cannot be made smaller or lower in cost by combining lumped constant components. ) IJ tube circuits, semi-coaxial filters using high dielectric materials, isolators that utilize the material properties of ferrite, filters that utilize the elastic vibration of crystals, functional components such as oscillators, functional modules, etc. The shape and size will be determined as a unit. Also,
In the high-frequency circuit section, it is necessary to mix contradictory functions such as a transmitting section aiming for high output and a receiving section receiving minute power, so there are mounting constraints due to signal flow and mounting constraints to prevent interference. There is. Therefore, the size of the casing of the high frequency circuit section is greatly influenced.

[Conventional technology]

FIG. 5 shows an example of a component mounting structure of a conventional high frequency circuit section. Referring to this figure, a flat printed wiring board 3 with wiring or a circuit pattern provided on the side plane is provided between a lower case 1 and an upper case 2 constituting a shield case. On one side, there is a semi-coaxial filter 4 made of high dielectric material and miniaturized.
A filter 5 whose frequency is different from that of the filter 4 is a filter that uses a semi-coaxial resonator (the size of which is determined by frequency characteristics, etc.), and a metal cap that is used electromagnetically to configure a functional circuit such as a voltage controlled oscillator. Lead components and relatively large-volume functional components or functional modules, such as hermetically sealed functional modules 6 and 7 and a volume 8 for adjusting frequency characteristics, are mounted. on the other hand,
A strip line and a lumped constant chip component 10 are mounted on the opposite side of the printed wiring board 3 or a sub-printed board 9 provided on the functional module 7.

[Problem to be solved by the invention]

In the component mounting structure of the high frequency circuit section described above, the filters 4 and 5, the functional modules 6.7, the volume 8, etc. mounted on the upper surface side of the flat printed wiring board 3 are components with relatively large volumes. However, since the size of each is determined by the circuit frequency etc., the height from the printed wiring board 3 is also different. Therefore, the largest circuit component, such as the filter 4; together with the upper case 2;
When determining the size of , there will be wasted space between the lower parts 5, 6.
It is not possible to improve the component mounting efficiency within the housing. Furthermore, the use of the sub-printed board 9 contributes to improving the component mounting density within the housing, but the mounting direction of the chip components 10 etc. on the sub-printed board 9 is different from the mounting direction of circuit components on the printed wiring board 3. Therefore, it becomes necessary to decentralize the implementation work, which causes problems such as difficulty in automating the implementation.

As described above, in the component mounting structure of the high-frequency circuit section of conventional mobile communication devices, it is difficult to miniaturize the case and automate component mounting by high-density mounting of components by effectively utilizing the space inside the case. .

Therefore, the present invention enables circuit components including large circuit components and small circuit components such as functional components and functional modules with different height dimensions to be mounted spatially at high density in a small housing, and The purpose of the present invention is to provide a mounting structure for circuit components that allows easy automation of mounting work.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a circuit component mounting structure in which a large circuit component and a small circuit component having different height dimensions are mounted on a wiring board that is partitioned vertically within a housing.
The wiring board is a resin molded wiring board having a flexible wiring board on which circuit backs are formed on both sides, and a resin substrate integrally molded with the flexible wiring board on one side of the flexible wiring board. Large circuit components with different height dimensions are mounted on the resin board side surface of the molded wiring board, and resin molding is carried out according to the difference in height dimension of the large circuit components so that the heights of the tops of the large circuit components are almost the same. The resin board side surface and the flexible wiring board side surface of the wiring board are provided with unevenness, and small-sized parts are formed in the concave area of the flexible wiring board located on the back side of the convex raised area on the large circuit component mounting side of the resin board. The configuration is equipped with circuit components.

[For production]

When mounting circuit components, first, small circuit components are mounted on the circuit pattern surface of the resin substrate formation side of the flexible wiring board, and then the resin substrate is mounted integrally with the flexible wiring board on one side of the flexible wiring board. By molding, a resin molded wiring board having required unevenness on both sides is formed. If necessary, a ground pattern for grounding large circuit components is formed on the resin board side surface of the molded resin molded wiring board. Next, small circuit components are mounted on the flexible wiring board side surface of the resin molded wiring board, that is, the outer circuit pattern surface of the flexible wiring board, and large circuit components are mounted on the resin board side surface of the resin molded wiring board. , connect lead terminals of large circuit components to circuit patterns on a flexible wiring board.

In the circuit component mounting structure having the above configuration, the large circuit components are placed on the resin board side of the resin mold wiring board so that the heights of the tops of the large circuit components are almost the same due to the unevenness formed on both sides of the resin mold wiring board. Since it can be mounted, it is possible to prevent wasted mounting space from being created on the side where large circuit components are mounted. On the other hand, it is necessary to secure a mounting space for small circuit components between the concave area of the flexible wiring board located on the back side of the raised convex area of the large circuit component mounting surface of the resin board and the wall surface of the casing. This makes it possible to mount a large number of small circuit components on a flexible wiring board while minimizing the space between the flexible wiring board side surface of the resin molded wiring board and the housing wall. Become.

Furthermore, small circuit components can be placed inside the resin substrate in areas where the large circuit component mounting side of the resin substrate is raised in a convex shape, making it possible to mount small circuit components on both sides of the flexible wiring board. This makes it possible to increase the component mounting area of the flexible wiring board.

Therefore, large circuit components and small circuit components having different height dimensions can be mounted in the housing at a high density without wasting space, and the housing can be made smaller. Furthermore, since it is possible to reduce the number of sub-printed boards, it is possible to prevent the component mounting work from being distributed, and the automation of the component mounting work is facilitated.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view of a component mounting structure of a high frequency circuit section of a mobile communication device showing an embodiment of the present invention. Referring to FIG. 1, a wiring board 13 provided between a lower case 11 and an upper case 12 constituting a shield housing includes a flexible wiring board 14 and a resin board 15 integrally molded on one side of the flexible wiring board 14. It is a resin molded wiring board having. As the material for the resin substrate 15, for example, resins such as epoxy, urethane, and silicone can be used.

On the surface of the resin molded wiring board 13 on the resin board 15 side, for example, a semi-coaxial film 1 made of a high dielectric material is used to reduce the size.
6 or filter 1 with a different frequency from this filter 16.
7 and a functional module 18 which is hermetically sealed with a metal cap in an electromagnetic manner to constitute a voltage controlled oscillator, etc., which are relatively large and have different height dimensions are mounted. Although the height dimensions of these large circuit components 16 to 18 are different from each other, the height dimensions of the large circuit components 16 to 18 are
Large circuit components 16~ so that the heights of the tops of 18 are almost the same
Resin molded wiring board 1 according to the difference in height dimension of 18
Required unevenness is provided on the resin substrate 15 side surface and the flexible wiring board 14 side surface of No. 3. That is, the distance between the resin monolithic wiring board 13 and the upper case 12 changes to correspond to the height of the large circuit components 16 to 18 to be mounted, and the large circuit component mounting surface side of the resin board 150 has a convex shape. A concave region 14a of the flexible wiring board 14 is formed on the back side of the raised region 15a.

When such a resin molded wiring board 13 is used, a large circuit component with the maximum height (filter 16 here)
The resin board 15 is made to have the minimum thickness at the location 15b where the flexible wiring board 1 is mounted, and no small circuit components are mounted on the flexible wiring board 14 on the back side of the location 15b.
4 and the lower case 11 is minimized. By forming in this way, the casing can be made smaller.

On the other hand, the flexible wiring board 14 has a concave region 14a on the back side of the region 15a where the large circuit component mounting surface side of the resin board 150 is raised in a convex shape.
A mounting space can be secured between the concave area 14a and the lower case 11 for mounting relatively small small circuit parts such as small circuit parts 19 and 20 (chip parts 19 and volume 20). Further, by appropriately setting the thickness of the convex region 15a of the resin substrate 15, it becomes possible to arrange the small circuit component 19 inside the resin substrate 15. In this way, the concave area 1 of the flexible wiring board 14
4a, small circuit components 19 are placed on both sides of the flexible wiring board 14.
．． 20, the component mounting area of the flexible wiring board 14 increases.

FIG. 2 shows in detail the cross-sectional structure of the flexible wiring board 14 before molding, and the flexible wiring board 14 has a flat sheet shape. Referring to FIG. 2, the flexible wiring board 14 has an insulating film 21 made of, for example, polyimide film, polyetherimide film, etc., and has a required circuit pattern 22 having through holes on both sides of the insulating film 21. A solder resist 23 is formed using a common printed wiring board manufacturing technique.

To mount the circuit components, first, as shown in FIG. 2, the required small circuit components 1 are placed on the resin board formation side of the flexible wiring board 14, which has the circuit patterns 22 on both sides.
Implement 9. Next, as shown in FIG.
5, and a resin substrate 15 integral with the flexible wiring substrate 14 is molded by vacuum forming, injection molding, or the like. At this time, the flexible wiring board 14 itself is also molded into an uneven shape in the molds 24 and 25 by the pressure during molding, and is integrated with the resin board 15.

Further, the small circuit component 19 mounted on the flexible wiring board 14 is embedded in the resin board 15. After that, as shown in FIG. 4, the resin substrate 1 of the resin molded wiring board 13 is
A ground pattern 26 for grounding the large circuit components 16 to 18 is formed on the 5-side surface as necessary.

Next, as shown in FIG.
The surface on the flexible wiring board 14 side, that is, the flexible wiring board 1
Small circuit components 19 and 20 are mounted on the outer circuit pattern surface of 4, large circuit components 16 to 18 are mounted on the surface of the resin molded wiring board 13 on the resin substrate 15 side, and lead terminals of the large circuit components 16 to 18 are mounted. It is connected to the circuit pattern on the flexible wiring board 14 by soldering.

Although the illustrated embodiments have been described above, the present invention is not limited to the embodiments described above. For example, the flexible wiring board 14 of the resin molded wiring board 13 has a circuit pattern of three or more layers. It may be something. Furthermore, the small circuit components mounted on the flexible wiring board 14 are not limited to chip-shaped components, but may also be dip-shaped components. Furthermore, the present invention can be similarly applied to component mounting structures other than the high frequency circuit section of a mobile communication device.

〔Effect of the invention〕

As is clear from the above description, according to the configuration of the present invention, the unevenness provided on the resin molded wiring board can prevent wasted mounting space from being created on the side where large circuit components are mounted, and also reduce the amount of space on the resin molded wiring board. It becomes possible to mount a large number of small circuit components on the flexible wiring board while minimizing the space between the flexible wiring board side surface and the housing wall surface. Furthermore, small circuit components can be placed inside the resin substrate in areas where the large circuit component mounting side of the resin substrate is raised in a convex manner, making it possible to mount small circuit components on both sides of the flexible wiring board. This makes it possible to increase the component mounting area of the flexible wiring board. Therefore, it is possible to provide a circuit component mounting structure in which the casing can be made smaller and the component mounting work can be easily automated.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a main part of a high-frequency circuit section of a Sugido communication device showing an embodiment of the present invention; FIG. 2 is a cross-sectional view of a main part of the flexible wiring board shown in FIG. 1 before molding; FIG. 3 is a sectional view of a main part showing the molding process of a resin board, FIG. 4 is a sectional view of a main part of a completed resin molded wiring board, and FIG. 5 is a sectional view showing a conventional circuit component mounting structure. In the figure, 11 is a lower case, 12 is an upper case, 1
3 is a resin molded wiring board, 14 is a flexible wiring board, 1
4a is a concave region, 15 is a resin substrate, 15a is a convex region,
16 to 18 indicate large circuit components, and 19.20 indicate small circuit components. DESCRIPTION OF SYMBOLS 11... Lower case (housing) 14... Flexible wiring board 14a... Concave area 15... Resin board 15a... Convex area Cross-sectional view of flexible wiring board before molding 2 Figure 1'I Cross-sectional view showing the molding process of the resin substrate Figure 3: Cross-sectional view of the completed resin molded wiring board Fourth factor

Claims (1)

[Claims] 1. In a circuit component mounting structure in which a large circuit component and a small circuit component having different height dimensions are mounted on a wiring board that is partitioned vertically within a housing (11, 12), a circuit pattern is formed on both sides of the wiring board. A resin molded wiring board (13) having a flexible wiring board (14) and a resin board (15) integrally molded with the flexible wiring board on one side of the flexible wiring board, Large circuit components (16 to 18) with different height dimensions are mounted on the resin board side surface of the molded wiring board, and the height dimensions of the large circuit components are adjusted so that the heights of the tops of the large circuit components are almost the same. According to this, unevenness is provided on the resin board side surface and the flexible wiring board side surface of the resin molded wiring board, and the flexible part is located on the back side of the region (15a) where the large circuit component mounting surface side of the resin board is raised in a convex shape. A circuit component mounting structure characterized in that small circuit components (19, 20) are mounted in a concave area (14a) of a flexible wiring board.