JP2000091728A - Method for mounting parts on printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To more easily and surely increase the packaging density of a printed wiring board by utilizing spaces under parts mounted on the printed board with spaces among them. SOLUTION: When parts 10 having terminals constituting signal lines on both sides are mounted on a printed wiring board 1, the parts 10 can be mounted on the board 1 by interposing the parts 10 between an extension terminal section 9 performed on parts 3 and a connection pad 2A performed on the board 1, and electrically connecting the parts 10 to the terminal section 9 and pad 2A. Therefore, the packing density of the printed board 1 as a printed wiring board can be increased easily and surely. When a plurality of extension terminal sections 9 are provided so that the sections 9 may be connected to the terminals on both sides of the parts 3 and, at the same time, a plurality of connection pads are provided at the positions corresponding to the terminal sections 9 on the printed board 1, a plurality of parts 10 can be mounted on both sides of the parts 3 and the packaging density on the printed board 1 can be increased further.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mounting components on a printed wiring board, and more particularly to a method suitable for further increasing the mounting density of components mounted on the printed wiring board.

[0002]

2. Description of the Related Art In recent years, printed wiring boards have been mounted at a high density, and not only the components mounted thereon have been reduced in size, but also other components have to be mounted on the components. In some cases, a component mounting area is further secured by the use of such components. A prior art of such a printed wiring board is shown in FIG. 3, in which a lead wire 4 of a component 3 is connected to a connection pad 2 formed on a printed board 1,
The component 3 is mounted on the printed circuit board 1 so as to float over the space. A smaller component 5 is mounted on the component 3.

[0003] In addition to the connection pads 2, a circuit pattern 6 connected thereto is formed on the printed board 1, and a through hole 7 is formed at a desired position of the circuit pattern 6. By mounting a component 8 different from the component 3 described above on the connection pad, the entire printed wiring board is configured.

[0004]

By the way, the above-mentioned prior art printed wiring board is required to increase the mounting density.
Although the component 5 is mounted on the component 3, the component 5 that can be mounted on the component 3 is a chip component, and one terminal on one end functions as a signal line, while the terminal on the other end is a power supply line. Other components that only function as a signal line and all of the terminals on both sides function as signal lines cannot be mounted on the component 3, and the mounting density of the components that function as signal lines on both sides is further increased. There is a problem that can not be. Further, when the components 3 are arranged on the printed circuit board 1 with a space therebetween as described above, there is a problem that the space below the components is wasted.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, an object of the present invention is to use a space below a component mounted on a printed circuit board with a space therebetween, and to mount components functioning as signal lines on both sides. It is another object of the present invention to provide a component mounting method for a printed wiring board, which can more easily and surely increase the mounting density.

[0006]

According to the method of the present invention, a printed circuit board having a first component mounted on a printed circuit board with a space therebetween is connected to a terminal on one side of the bottom of the first component in advance. A second component is interposed between the extension terminal portion formed as described above and a connection pad previously formed at a position corresponding to the extension terminal portion on the printed circuit board.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. 1 and 2 show an embodiment of a component mounting method for a printed wiring board according to the present invention. In these drawings, the same reference numerals as those in FIG. 3 denote the same or corresponding components. As shown in FIG. 1, a component 3 as a first component is mounted on a printed board 1 with a space therebetween. The component 3 is mounted on the printed circuit board 1 by connecting the tip of a lead wire 4 drawn from the component 3 to a connection pad 2 provided on the printed circuit board 1. The component 3 has terminals on both sides forming signal lines. This is the same as the prior art shown in FIG.

In the method of the present invention, an extension terminal 9 is provided for each of the terminals on one side of the component 3 mounted on the printed board 1, and the extension terminal 9 and
The component 10 as the second component can be mounted between the printed circuit board 1 and the connection pad 2A facing the component. That is, as shown in FIG.
It is formed to extend to the bottom of the component 3 while being connected to each terminal provided on both sides of the component 3, and is formed by, for example, plating. On the other hand, connection pad 2A
Are the components 3 on the printed circuit board 1 as shown in FIG.
And is connected to the circuit pattern 6 at a position corresponding to the extension terminal portion 9. The component 10 is a chip component whose terminals on both sides have the function of a signal line.

The component 10 is mounted by interposing the component 10 between the extension terminal 9 of the component 3 and the connection pad 2A of the printed circuit board 1. At this time, the extension terminal 9
As is clearly shown in FIG.
a is formed, and the printed circuit board 1 is mounted when the component 10 is mounted.
By mounting the solder bump 11B, which is the lower terminal of the component 10, on the connection pad 2A, and engaging the solder bump 11A of the component 10 with the groove 9a of the extension terminal portion 9 of the component 3, Part 1 between part 3
0 is implemented.

In the component mounting method according to the embodiment, when a component 10 having both terminals forming a signal line is mounted, an extension terminal 9 formed in advance on the component 3 and an extension terminal 9 formed in advance on the printed circuit board 1 are formed. The component 10 is interposed between the connection pad 2A and the connection pad 2A.
Can be implemented. As a result, when compared to the prior art, even if the component 10 has both terminals forming signal lines,
The components 3 can be mounted by effectively utilizing the space, and the mounting density as a printed wiring board can be easily and reliably increased. In this case, FIG. 1 and FIG.
As shown in FIG. 5, a plurality of extension terminal portions 9 are provided so as to be connected to each of both terminals of the component 3, and
If a plurality of connection pads 2A are provided at positions corresponding to the extension terminal portions 9 on the top, a plurality of components 10 can be mounted on both sides of the component 3, and the mounting density can be further increased.

Further, as shown in the illustrated embodiment, if the extension terminal portion 9 is provided with a groove 9a for engaging with the solder bump 11A of the component 10, the positioning of the component 10 becomes easy and the component mounting work is simplified. Can also be.

[0012]

As described above, according to the present invention, the second terminal is provided between the extension terminal portion formed in advance on the first component and the connection pad formed in advance on the printed circuit board. Since the second component can be mounted by interposing the component, it is possible to mount even if the terminal on both sides is the second component forming the signal line, and the mounting density as a printed wiring board can be easily and reliably increased. There is an effect that can be raised.

[Brief description of the drawings]

FIG. 1 is a sectional explanatory view showing one embodiment of a method for mounting components on a printed wiring board according to the present invention.

FIG. 2 is an enlarged view of a main part when FIG. 1 is viewed from the left.

FIG. 3 is an explanatory diagram showing an example of a conventional technique.

[Explanation of symbols]

1 ... printed circuit board, 2, 2A ... connection pad, 3 ... parts,
4 ... lead wire of component 3, 9 ... extension terminal part, 10 ... component,
11A, 11B: solder bumps of the component 10;

Claims (1)

[Claims] 1. A printed wiring board on which a first component is mounted on a printed circuit board with a space therebetween, an extension terminal portion formed in advance on the bottom of the first component by connecting to a terminal on one side thereof; A component mounting method for a printed wiring board, wherein a second component is interposed between a connection pad formed at a position corresponding to the extension terminal portion on a printed circuit board in advance.