JPH0128515B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for connecting electronic components to a multilayer printed wiring board with a common inner layer pattern. Compared to double-sided printed wiring boards, it has improved packaging density and is more resistant to noise, but it also has drawbacks such as high manufacturing costs and the difficulty of changing circuits on completed boards. It was hot.

In particular, as a method to reduce manufacturing costs as much as possible, there is a method of using the mass lamination method to standardize the inner layer patterns used for power supply and grounding of components.This makes it possible to mass produce inner layer patterns and reduce costs. We are planning to reduce this.

However, the above method has the following drawbacks.

In other words, as shown in Fig. 1, if you are trying to mount a component with a large diameter 2 at the connection part with the board on the board 1, or a component with a large mounting hole 3 for a mounting part such as a screw (hereinafter referred to as a discrete component), This will cause an electrical short circuit in the inner layer pattern 4, and when attaching these parts, it is necessary to create mounting holes in the inner layer pattern 4 corresponding to the parts to be attached, and as a result, each multilayer board has its own unique characteristics. It was necessary to prepare a board with a pattern, which was an obstacle to the provision of inexpensive multilayer printed wiring boards and to standardization.

The present invention has been made in view of the above points, and when a conventionally used inner layer pattern is used as it is and there is a risk of electrical short circuit with this pattern, the copper foil portion of the pattern is removed. To provide a method for connecting electronic components of a multilayer printed wiring board, which eliminates the influence of the above-mentioned short circuit on other parts within the same layer by separating the inner and outer parts.

An embodiment to which the present invention is applied will be described below with reference to FIG. 2 and the following drawings.

FIG. 2 shows an embodiment to which the present invention is applied,
FIG. 2 is an enlarged external view of a portion of the multilayer printed wiring board with a portion thereof cut away.

In the figure, the multilayer printed wiring board is composed of a plurality of layers, including an outer layer 11 on the surface and a plurality of inner layers 12 (only one inner layer is not shown in the figure). The inner layer 12 has a copper foil portion 14 whose surface is patterned over the entire surface except for a plurality of non-copper foil portions (hereinafter referred to as circular clearances) 13.

Furthermore, a component attachment hole 15 is provided through the outer layer 11 and the inner layer 12, through which a lead wire of a discrete component placed on the outer layer 11 can be inserted to make electrical connection with a desired inner layer.

Reference numeral 16 denotes a hole provided to divide the copper foil portion on the surface of the inner layer 12 into two when the lead wire inserted into the component mounting hole 15 is thick. this hole 1
Reference numeral 6 indicates a non-through hole that is drilled using a general hole punching machine (not shown) and whose inside is not plated with copper.

Reference numeral 17 indicates a wiring pattern on the surface of the outer layer 11.

3 shows a plan view of only the inner layer 12 of FIG. 2 taken out and viewed from above, and FIG. 4 shows a plan view of the outer layer 11 of FIG. 2 seen from above.

The operation of the multilayer printed wiring board connection method of the present invention as described above will be explained.

First, the diameter of the clearance 13 of the inner layer 12 is 2
mm, and has a pattern that extends over the entire surface at regular intervals as shown in FIG.
If 5 is small, an electrical short circuit will occur in the inner layer 12 pattern, making it impossible to mount components.

Therefore, a plurality of holes 16 are provided so that the copper foil portion 14 of the inner layer 12 can be electrically separated into two parts, an inner copper foil portion 14a and an outer copper foil portion 14b as shown in FIG.

The hole 16 separates the inner layer copper foil portion in contact with the lead wire from the outer copper foil portion, thereby preventing short circuits in the inner layer pattern.

Note that the hole 16 has an adjacent clearance 13.
As mentioned above, this hole 16 is a non-through hole for cutting the copper foil between the outer layer 11 and the outer layer 11. It is best to perform the drilling process for this hole 16 after the etching of the outer layer 11 is completed.

As described above, the present invention enables electronic components that could not be mounted conventionally to be mounted on a multilayer printed wiring board with a common inner layer pattern without preparing a new inner layer pattern. It is expected that this will greatly contribute to the realization of standardization, and will also greatly contribute to reducing product costs, shortening delivery times, and reducing man-hours.

[Brief explanation of drawings]

FIG. 1 shows a conventional method for connecting a multilayer printed wiring board, FIG. 2 shows an enlarged partially cutaway schematic diagram of a multilayer printed wiring board according to an embodiment of the present invention, and FIG.
2 is a plan view showing the inner layer 12 taken out, and FIG. 4 is a plan view showing only the outer layer 11 shown in FIG. 2 taken out. DESCRIPTION OF SYMBOLS 11... Outer layer, 12... Inner layer, 13... Clearance, 14, 14a, 14b... Copper foil part (inside, outside), 15... Component mounting hole, 16... Hole.

Claims (1)

[Claims] 1. In a method for connecting electronic components to a multilayer printed wiring board having a common interior pattern, a plurality of non-copper foil parts (clearances) are provided in the interior pattern, and the electronic component is large enough to destroy part of the clearances. When the electronic component is mounted, the copper foil portions intervening in each of the other multiple clearances located near the clearance to be destroyed are cut from the surrounding copper foil portions, and the copper foil portions in contact with the electronic components are cut off from the surrounding copper foil portions. A method for connecting electronic components to a multilayer printed wiring board, characterized in that the electronic component is separated from the board and formed into an arc.