JPH09246725A - Through hole of multilayer printed circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ideally match the connection surfaces of the upper layer to the lower layer of a multilayer printed circuit board by a method wherein a through hole, having non-circulate cross section, not the normally used circular cross section, is used. SOLUTION: A non-circular through hole 3, not the circular through hole used in the past, is perforated, lands 2a and 2b, having a flange part which covers a conductive material, are formed and printed pattern 1a and 1b are connected to the lands. Accordingly, the connection point to the lands 2a of the upper layer printed pattern 1a can be moved to the position of the printed pattern 1c, and the connection point to the land 2b of the lower layer printed pattern 1b can be moved to the position of a printed pattern 1b. As a result, the connection of the upper and the lower layers of the multilayter printed circuit board has high degree of freedom and versatility, the conduction between the front and the back sides of the multilayer printed circuit board can be secured, and heat dissipating property can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a through hole of a multilayer printed circuit board, which is used for ensuring electrical continuity between layers.

[0002]

2. Description of the Related Art FIG. 3 is a diagram showing through holes in a conventional multilayer printed circuit board. As shown in the drawing, a circular through hole 5 is bored in the multilayer printed board 4, lands 2a and 2b having a flange portion coated with a conductive material are formed in the circular through hole 5, and lands 2a and 2b are formed. Print patterns 1a and 1b made of a conductive material are connected to the multilayer printed circuit board 4.

[0003]

However, in such a through hole of the conventional multilayer printed circuit board 4, the connection between the print pattern 1a of the upper layer (front) and the print pattern 1b of the lower layer (back) of the multilayer printed circuit board 4 is made. Is only a small hole portion of the circular through hole 5, and there is a problem that the degree of freedom and flexibility of the connection point is poor, and it is difficult to ideally match the connection surface between the upper layer and the lower layer of the multilayer printed circuit board 4. However, the surface area of the circular through hole 5 is small only in the small hole portion, and the heat dissipation effect is insufficient.

The present invention has been made to solve the above-mentioned problems, and provides flexibility and flexibility in connection points between upper and lower printed patterns of a multilayer printed circuit board to facilitate ideal connection surface alignment. Another object of the present invention is to provide a through hole of a multilayer printed circuit board having good heat dissipation characteristics.

[0005]

In order to achieve this object, in the present invention, a through hole set to secure conduction between layers of a multilayer printed circuit board has a cross-sectional shape of the through hole. A non-circular shape other than the commonly used circular shape is used.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 (a) is a view showing an embodiment of a through hole of a multilayer printed circuit board according to the present invention, and FIG. 1 (b) is a sectional view taken along line AA of FIG. 1 (a). It is a figure. As shown in the figure, the multi-layer printed circuit board 4 is not formed with the circular through hole which is conventionally used, but is formed with a non-circular through hole 3 having a rectangular shape with a rounded end if necessary. , The non-circular through hole 3 is formed with lands 2a, 2b having a collar portion coated with a conductive material,
Print patterns 1a and 1b made of a conductive material on the multilayer printed circuit board 4 are connected to the lands 2a and 2b.

In such a non-circular through hole 3, the connection point of the upper layer print pattern 1a to the land 2a can be moved to, for example, the position of the print pattern 1c, and the lower layer print pattern 1b.
Can be moved to, for example, the position of the printed pattern 1d, and the upper and lower layers of the multilayer printed circuit board have a large degree of freedom and flexibility, and ensure conduction between the front and back sides of the multilayer printed circuit board. It is possible to improve the heat dissipation characteristics.

FIG. 2 (a) is a view showing another embodiment of the through hole of the multilayer printed board according to the present invention, and FIG. 2 (b) is a view showing the AA cross section of FIG. 2 (a). is there. As shown in the figure, by forming a non-circular through hole 3a having a hook-shaped rectangular shape (the end portion may be rounded if necessary), the connection point of the upper layer print pattern 1a to the land 2a becomes For example, it can be moved to the position of the print pattern 1c, and the connection point of the lower layer print pattern 1b to the land 2b can be moved to, for example, the position of the print pattern 1d. Further, it has a greater degree of freedom and flexibility, it is possible to secure conduction between the front and back of the multilayer printed circuit board, and it is possible to further improve the heat dissipation characteristic.

[0009]

As described above, in the through-hole of the multilayer printed circuit board according to the present invention, it is possible to provide a large number of degrees of freedom and flexibility in the connection points between the print patterns on the front and back of the multilayer printed circuit board and the lands. As a result, it becomes easy to ideally match the connecting surfaces between the upper layer and the lower layer of the multilayer printed circuit board, and it is possible to improve the heat dissipation characteristics.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a through hole of a multilayer printed circuit board according to the present invention.

FIG. 2 is a view showing another embodiment of the through hole of the multilayer printed board according to the present invention.

FIG. 3 is a diagram showing through holes of a conventional multilayer printed circuit board.

[Explanation of symbols]

 1a Print pattern 1b Print pattern 1c Print pattern 1d Print pattern 2a Land 2b Land 3 Non-circular through hole 3a Hook type non-circular through hole 4 Multi-layer printed circuit board 5 Circular through hole

Claims (1)

[Claims] 1. A through hole set to secure conduction between layers of a multilayer printed circuit board, wherein a non-circular shape other than a circular shape which is usually used as a cross-sectional shape of the through hole is used. Through hole of multilayer printed circuit board.