JP2001028490A - Substrate-mounting structure of electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To utilize a disposal substrate as heat radiation, a heat guide, and earth by jointing a printed wiring board interconnected in a through hole to an electronic component body connected to the printed wiring board for a product for releasing the generation heat of the electronic component. SOLUTION: A disposal substrate 14 that is used as a heat sink with a through hole 13 cut to proper size is jointed to an electronic component 12 that is connected to a printed wiring board 11 for a product where an excessive part is cut for generating heat by a locking tool 15. When a copper pattern exposure part 16 exists in the disposal substrate 14, the copper pattern exposure part 16 is mounted so that the copper pattern exposure part 16 is brought into contact with the electronic component 11. In this manner, the disposal substrate 14 with the through hole 13 is utilized as the heat sink, thus releasing heat in the electronic component without increasing costs, and hence easily miniaturizing the printed wiring board due to the reduced size of a terminal device or the like, and achieving the high packaging density of the electronic component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for mounting an electronic component on a printed circuit board.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 7, a printed wiring board 2 in which electronic components 1 are interconnected by through holes.
When the electronic component 1 generates heat at a high temperature, a heat radiating plate 3 is attached to the electronic component 1 and an electronic component that is weak against external noise such as a CPU is sufficiently provided around the mounting position. When the ground pattern is not provided, the electronic component is surrounded by the shield case 4 to take measures against heat radiation and noise of the electronic component.

In recent years, such measures against heat radiation and noise of electronic components have been increasingly regarded as important due to the miniaturization of printed wiring boards accompanying the miniaturization of terminal devices and the like, the increase in mounting density of electronic components, and the like.

[0004]

However, if a dedicated heat radiating plate or shield case as shown in FIG. 7 is provided for each electronic component requiring a heat radiation countermeasure or a noise countermeasure, the cost of the apparatus increases. There is a problem to say.

[0005] By the way, the printed wiring board 2 as shown in FIG. 7 is cut off an unnecessary portion 5 as shown by oblique lines in FIG.
The remaining part is mounted on a terminal device or the like as a product substrate.

The inventors of the present invention carried out an experiment on heat radiation by directly attaching a cut-out printed wiring board (hereinafter referred to as a discarded board) to an electronic component that generates heat.
It has been confirmed that the heat generated from the electronic components is effectively transmitted to the interconnected conductor patterns by the through-holes of the discarded substrate and is radiated. In addition, we conducted a thermal fluidity experiment by disposing a discard substrate around the heat-generating electronic component.The heat generated from the electronic component flows and is guided by the discard substrate. It has been confirmed that there is no adverse effect on other electronic components arranged. Further, discarded substrates are provided around the electronic components susceptible to noise and on the back side of the product board to which the electronic components are connected, and when the through holes of these discarded substrates are electrically connected to the ground of the product board, It was confirmed that the conductor pattern interconnected by the through holes in the substrate increased the ground area near the electronic component, and that a shielding effect was obtained.

Accordingly, an object of the present invention made in view of the above point is that the cost of the apparatus can be reduced by making the discarded substrate usable as a radiator plate, a heat guide plate, or a ground plate. It is an object of the present invention to provide a substrate mounting structure for an electronic component.

[0008]

According to a first aspect of the present invention, there is provided an electronic component substrate mounting structure which is connected to a main body of an electronic component connected to a product printed wiring board by through holes. Wherein the printed circuit board is joined to dissipate heat generated in the electronic component.

According to the first aspect of the present invention, a discard substrate interconnected by through holes can be used as a printed wiring board to be joined to an electronic component. By joining with a stopper or an adhesive, more effective heat radiation becomes possible.

According to a second aspect of the present invention, in the electronic component mounting structure according to the first aspect, an opening larger than the through hole is formed in the printed wiring board bonded to the electronic component. Things.

According to the second aspect of the present invention, since the ventilation is improved by forming the openings, it is possible to further improve the heat radiation.

The invention according to claim 3 is the invention according to claim 1 or 2
Wherein the printed wiring board bonded to the electronic component is soldered to a solid pattern portion of the product printed wiring board.

According to the third aspect of the present invention, the heat generated in the electronic component can be dispersed to the product printed wiring board side via the printed wiring board bonded to the electronic component. It is possible to increase.

According to a fourth aspect of the present invention, there is provided an electronic component substrate mounting structure, wherein the printed circuit board is joined to the product printed circuit board so as to surround the electronic component connected to the product printed circuit board. Wherein the heat generated by the electronic component is made to flow.

According to the fourth aspect of the invention, it is possible to guide the heat generated from the electronic component by the printed wiring board disposed therearound so as not to adversely affect other electronic components.

According to a fifth aspect of the present invention, there is provided an electronic component substrate mounting structure, comprising: a periphery of an electronic component connected to the product printed wiring board; and a back side of the product printed wiring board corresponding to a connection portion of the electronic component. And first and second printed wiring boards interconnected by through holes, respectively, and electrically connect the through holes of the first and second printed wiring boards to the ground of the product printed wiring board. Thus, the ground area in the vicinity of the electronic component is increased.

According to the fifth aspect of the present invention, since the ground area near the electronic component increases, the electronic component can be effectively protected from external noise.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a first embodiment of the present invention. In this embodiment, a heat-generating electronic component 12 connected to a product printed wiring board (hereinafter, referred to as a product board) 11 from which an unnecessary portion has been cut out.
Then, a discarded substrate 14 having a through hole 13 cut to an appropriate size is joined to the discarded substrate 1 by a stopper 15.
4 is used as a heat sink. If the discard substrate 14 has the copper pattern exposed portion 16, the copper pattern exposed portion 16 is attached so as to be in contact with the electronic component 11.

As described above, by using the discarded substrate 14 having the through-holes 13 as a heat radiating plate, it is possible to implement measures for radiating the electronic components without increasing the cost, and to reduce the size of the terminal device or other printed wiring. It is also possible to easily cope with a reduction in the size of the substrate and an increase in the mounting density of electronic components.

FIG. 2 is a perspective view showing a second embodiment of the present invention. This embodiment is different from the first embodiment in that a plurality of openings 21 having a diameter larger than that of the through holes 13 are formed in the discarded substrate 14 to improve ventilation. Therefore, according to this embodiment, heat dissipation can be further improved.

FIG. 3 is a perspective view showing a third embodiment of the present invention. This embodiment is different from the second embodiment in that a through-hole 23 for attaching a discard substrate 14 used as a heat sink is formed in the solid pattern portion of the product substrate 11. A soldering portion 24 to be inserted into 23 is formed, and this soldering portion 24 is inserted into the through hole 23 and soldered.

As described above, the soldering portion 24 is formed on the discard substrate 14 as a heat sink attached to the electronic component 12, and the soldering portion 24 is inserted into the through hole 23 formed in the solid pattern portion of the product substrate 11. Then, by soldering to the solid pattern portion, the conductor pattern of the discard substrate 14 can be connected to the solid pattern portion of the product substrate 11, so that the heat generated in the electronic component 12 can be removed through the discard substrate 14. Can also be dispersed on the side, and the heat dissipation can be further enhanced. Note that such a mounting structure is also effective when the opening 21 is not formed in the discarded substrate 14.

FIGS. 4A and 4B show a fourth embodiment of the present invention.
FIG. 4 (a) shows a perspective view and FIG.
(B) is a view on arrow A in FIG. 4 (a). In this embodiment, in a state where the product substrate 11 is mounted in the housing 26, the periphery of the heat-generating electronic components 12 connected to the product substrate 11 is divided into the product substrate 11, the upper surface 26 a and the side surface 2
6b, the substrate 14 is soldered to the through hole 27 formed in the product substrate 11 and is disposed in a U-shape to provide the substrate 14, and a ventilation hole 26c is formed in the side surface 26b surrounding the electronic component 12.

As described above, when the periphery of the electronic component 12 is surrounded by the discard substrate 14, the heat generated by the electronic component 12 is guided so as to flow out from the ventilation hole 26c of the side surface 26b of the housing 26. Product board 1
It is possible to effectively prevent other electronic components connected to 1 from being adversely affected by heat.

FIGS. 5A and 5B show a fifth embodiment of the present invention.
FIG. 5 (a) is a perspective view and FIG.
(B) is a view on arrow B in FIG. 5 (a). In this embodiment, in a state where the product substrate 11 is mounted in the housing 26, the surroundings of the heat-generating electronic components 12 connected to the product substrate 11 are surrounded by the product substrate 11 and the upper surface 26 a of the housing 26. As shown in FIG.
To provide a discarded substrate 14 in a square shape,
A ventilation hole 26c is formed in a portion of the upper surface 26a surrounding the electronic component 12.

Therefore, according to this embodiment, the heat generated in the electronic component 12 is guided so as to flow out of the ventilation hole 26c of the upper surface 26a of the housing 26, so that the fourth
As in the case of the embodiment, it is possible to effectively prevent other electronic components connected to the product substrate 11 from being adversely affected by heat.

In the fourth and fifth embodiments, it is possible to use a discarded substrate 14 having no through-hole as the discarded substrate 14. In this case, the discarded substrate 14 may be fixed to the product substrate 11 with an adhesive or the like. .

FIG. 6 shows a sixth embodiment of the present invention. FIG. 6 (a) is an exploded perspective view and FIG. 6 (b) is a side view. In this embodiment, a frame-shaped discard substrate 14a is arranged on the front side of the product substrate 11 so as to surround the electronic component 12 that is weak to noise and connected to the product substrate 11. Further, at the position corresponding to the connection portion of the electronic component 12 on the back surface side of the product substrate 11, a disposal substrate 14b is disposed as a whole, and these disposal substrates 14a, 14b are placed at appropriate positions through the disposal substrate 14a. Hole 13a, through-hole connected to ground of product substrate 11, and conductive pin 2 passed through through-hole 13b of discard substrate 14b
9 is fixed to the product board 11 by soldering, and the through holes 1 of the discarded boards 14a and 14b are
3a and 13b are electrically connected to the ground of the product substrate 11.

In this way, the discarded substrates 14a, 14a
The conductor pattern b increases the ground area near the electronic component 12, so that the electronic component 12 can be effectively protected from external noise.

[0030]

As described above, according to the present invention, the discarded substrate can be used as a radiator plate, a heat guide plate, or a ground plate. It is possible to easily cope with heat radiation measures and noise measures in downsizing, high mounting density of electronic components, and the like, and to effectively reduce the cost of the device.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is a perspective view showing a second embodiment.

FIG. 3 is a perspective view showing a third embodiment.

FIG. 4 is a diagram showing a fourth embodiment.

FIG. 5 is also a diagram showing a fifth embodiment.

FIG. 6 is a diagram showing a sixth embodiment.

FIG. 7 is a diagram for explaining a conventional technique.

FIG. 8 is a diagram showing an unnecessary portion in the printed wiring board.

[Explanation of symbols]

 Reference Signs List 11 Printed wiring board for product (product board) 12 Electronic component 13, 13a, 13b Through hole 14 Discarded board (printed wiring board) 15 Stopper 16 Copper pattern exposed part 21 Opening 23 Through hole 24 Soldering part 26 Housing 26a Top surface 26b Side surface 26c Ventilation hole 27 Through hole 29 Conducting pin

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takeshi Yaginuma 6-12-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo Fujitsu Eye Network Systems Co., Ltd. (72) Inventor Shuichi Ito 6, Nishishinjuku, Shinjuku-ku, Tokyo No. 12 No. 1 Fujitsu Eye Network Systems Co., Ltd. F-term (reference) 5E322 AA02 AA11 AB01 AB02 AB06 AB07 BA01

Claims (5)

[Claims] 1. A printed wiring board interconnected by through holes to a main body of an electronic component connected to a product printed wiring board so that heat generated in the electronic component is radiated. Characteristic electronic component board mounting structure. 2. The electronic component mounting structure according to claim 1, wherein an opening larger than the through hole is formed in the printed wiring board joined to the electronic component. 3. The electronic component board mounting structure according to claim 1, wherein the printed wiring board bonded to the electronic component is soldered to a solid pattern portion of the product printed wiring board. 4. A printed circuit board is provided in connection with the product printed circuit board so as to surround an electronic component connected to the product printed circuit board, and heat generated in the electronic component is made to flow. A substrate mounting structure for an electronic component, characterized in that: 5. First and second interconnected through holes on the periphery of an electronic component connected to the product printed wiring board and on the back side of the product printed wiring board corresponding to the connection portion of the electronic component. A second printed wiring board is provided, and a through-hole of the first and second printed wiring boards is electrically connected to a ground of the product printed wiring board to increase a ground area near the electronic component. A substrate mounting structure for an electronic component, wherein the substrate is mounted.