JP2589097B2 - Printed wiring board - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a printed wiring board, and more particularly to a printed wiring board in which lands are formed on intersections of a large number of grids, and two or more wiring channels are provided between the grids, and The present invention relates to a printed wiring board having a wiring pattern connected to the land.

(Prior Art) On a printed wiring board in which lands are formed on intersections of a large number of grids, have two or more wiring channels between the grids, and a wiring pattern is connected on the lands, the wiring An important issue is how to efficiently route patterns. That is, in this type of printed wiring board, a wiring pattern is connected to a large number of lands provided on a grid, and electrical connection between electronic components mounted on the printed wiring board is performed. However, as electronic components have become smaller and more multifunctional as of today, the wiring pattern of a printed wiring board for mounting the electronic components also needs to be made denser and smaller.

In addition, these wiring patterns are often formed using a CAD device.However, in order to facilitate the processing in the CAD device, a path where the wiring pattern is drawn, that is, a grid and a wiring channel are formed in advance, and these are formed. The wiring pattern is formed on the lattice or the wiring channel.

That is, in order to connect a wiring pattern to a land or a through hole formed on a printed wiring board using a CAD device, the following various conditions must be satisfied.

In order to enable high-density mounting of electronic components, each wiring pattern must be efficiently wired.

Each wiring pattern must be wired while maintaining a predetermined distance so as to prevent short circuit due to contact with each other.

Each wiring pattern must have a simple shape so that it can be processed by a CAD device.

Various printed wiring boards satisfying such conditions have hitherto been proposed, such as a "printed wiring board" disclosed in Japanese Patent Application Laid-Open No. Sho 60-194592 and a "high-speed printed circuit board" disclosed in Japanese Patent Application Laid-Open No. 60-92695. An example is shown in "Density printed wiring method". For example, a "printed wiring board" disclosed in Japanese Patent Application Laid-Open No. Sho 60-194592 is a "printed wiring board having two or more predetermined number of wiring channels in a grid, a grid having a number of wiring patterns equal to the predetermined number. In the grid, the number of wiring patterns is less than the predetermined number, and the wiring is arranged such that the spacing between the wiring patterns and the spacing between the wiring pattern and the grid pad become uniform within the grid having the predetermined number of wiring patterns. Printed wiring board ".

By the way, in the printed wiring board disclosed in Japanese Patent Application Laid-Open No. 60-194592, as shown in FIG. 5, each wiring pattern is wired from the grid pad directly to the wiring channel. Since a large space is formed between the grid pad from which the wiring pattern has been drawn and the grid pad adjacent thereto, it cannot be said that the wiring method is efficient. In addition, as shown in FIG. 5, when the wiring patterns have to be drawn from the diagonally positioned grid pads, the drawn wiring patterns are close to each other and cause a short circuit. There is a possibility. This may cause a similar problem in the high-density printed wiring method disclosed in Japanese Patent Application Laid-Open No. 60-92695.

Thus, the present inventors have analyzed the above-mentioned drawbacks of the prior art and found that the land (grid pad or through hole)
The present inventors have newly found that it is possible to obtain a good result by temporarily putting out a wiring pattern coming out of a lattice on a lattice, and have completed the present invention.

(Problems to be Solved by the Invention) The present invention has been made based on the above-described background, and the problem to be solved is inefficiency in drawing a wiring pattern from a land. And the wiring pattern is short-circuited.

An object of the present invention is to provide a printed wiring board that can achieve high-density mounting and eliminate problems such as short circuit between wiring patterns by more efficiently routing wiring patterns. is there.

(Means and Actions for Solving the Problems) Means adopted by the present invention to solve the above problems will be described with reference to FIGS. 1 to 4 corresponding to the embodiment. The lands (14) are formed on the intersections (12) of the grids (11), and two or more wiring channels (13) are formed between the grids (11).
In a printed wiring board having a wiring pattern (15) on a land (14), the wiring pattern (15) coming out of the land (14) is temporarily placed on a grid (11) and pulled out. At the intersection of the grid (11) and the wiring channel (13) formed between the land (14) from which the pattern (15) starts and another land (14) adjacent thereto, the wiring pattern (15) is It is bent at an angle of 45 ° to the direction of travel, and furthermore, this wiring pattern (15) is bent on the newly formed wiring channels (13) as many as necessary between the grids (11) passing through it. Printed wiring board (10) ".

Next, this configuration will be described in detail according to the specific example shown in the drawings.

1 to 4 show a printed wiring board (1) according to the present invention.
0), which is an enlarged plan view of a portion different from each other. In addition, this printed wiring board (1
In (0), lands (14) are formed on necessary intersections (12) of a large number of grids (11). Further, in the printed wiring board (10), a wiring pattern (15) is connected to an appropriate land (14), and the wiring pattern (15) is placed between the grids (11). When forming, use a CAD device to route wires (1
3) is formed between the gratings (11).

Each lattice (11) is shown by a dashed line in FIGS. 1 to 4, but is generally formed in units of 2.54 mm, and is formed on a printed wiring board (10) by a wiring pattern (15). ) CA
This is used as a reference line when mechanically forming with a D device or the like. Each of the grids (11) is further divided to form a wiring channel (13) for a plurality of wirings. This wiring channel (13) is formed on the entire printed wiring board (10) as shown by the dotted line in FIGS. 1 to 4, and is shown in FIGS. As shown by the two-dot chain line in the figure, another wiring channel (16) is appropriately set depending on the location.

In this printed wiring board (10), lands (14) are formed on arbitrary intersections (12) of the large number of grids (11). That is, as shown in FIGS. 1, 2 and 3, the land (14) is not limited to being formed on the intersection (12) of all the grids (11), but is shown in FIG. In some cases, as shown in (1), it is not formed on the intersection (12) of the grid (11).

A wiring pattern (15) is connected to an appropriate portion of these lands (14). The wiring pattern (15) coming out of the land (14) is once put on the grid (11) and pulled out. This drawn wiring pattern (15)
It is then bent at an angle of 45 ° to the direction of travel. The place where the wiring pattern (15) is first bent is a land (14) where the wiring pattern (15) starts and a wiring channel (13) formed between another land (14) adjacent thereto and a grid ( On the intersection with 11).

In this way, the wiring pattern (15) is taken out from the land (14), once put on the grid (11) and pulled out,
Thereafter, by bending at an intersection of the grid (11) and the wiring channel (13) at an angle of 45 ° with respect to the direction of travel, in the direction in which the wiring pattern (15) is to travel, especially this wiring pattern (15) Connected lands (14)
And the space between the lands (14) adjacent thereto can be used effectively. In addition, bending the wiring pattern (15) at an angle of 45 ° with respect to the traveling direction can effectively save space for forming another wiring pattern (15), as shown in FIG. It plays a role in using it. The reason is that the space formed by the four grids (11) adjacent to each other is a square, and in the case where a plurality of wiring patterns (15) are formed in this square while changing the traveling direction thereof, this wiring This is because, if the pattern (15) is bent at an angle of 45 ° with respect to the traveling direction, the pattern (15) can be easily made parallel to the other wiring patterns (15), so that it is the most efficient.

Furthermore, this bent wiring pattern (15)
It is further bent and connected to other necessary parts while satisfying the following conditions. That is, the wiring pattern (15) once bent is placed on a newly formed wiring channel (13) or another wiring channel (16) by a required number between the grids (11) passing therethrough. It can be bent further. The specific conditions for further drawing out the once bent wiring pattern (15) will be described for each case as follows. (A) A case where a number of wiring patterns (15) different from the number of wiring channels (13) are passed between the lands (14); in this case, as shown in FIGS. 1 and 4, bending is performed. Place the wiring pattern (15) on the grid (1) on another newly created wiring channel (16) between the lands (14).
Wire in parallel with 1). In this way, the bent wiring pattern (15) becomes the land (14).
Since the wiring is not biased between the wirings, the wiring pattern (15) is located farthest from each land (14). Therefore, the problem of short circuit can be sufficiently avoided.

In this case, in the printed wiring board (10) shown in FIG.
4) is not formed, and the wiring pattern (15) simply passes through the grid (11). In this case, the bent wiring pattern (15) (the lower pattern in the figure) is regarded as a land (14) formed on a grid (11) having no land (14). The wiring is wired in parallel with the grid (11) on another newly created wiring channel (16) between these lands (14).

(B) When the same number of wiring patterns (15) as the number of wiring channels (13) are passed between the lands (14); in this case, as shown in FIGS. 2 and 3, the bent wiring The wiring channel (13) located between the lands (14) and the wiring pattern (1)
The wiring channel (1) close to the land (14) where the 5) departed
3) Wiring on top.

(Embodiment) Embodiment 1 FIG. 1 shows a first embodiment of the present invention. In the first embodiment, the wiring pattern (1
The case of 5) is smaller than the number of wiring channels (13).

In the first embodiment, in addition to the wiring channel (13) between the lattices (11), another newly formed wiring channel (16) is set at the center of the wiring channel (13). The wiring pattern (15) is shifted on the wiring channel (16).

Embodiment 2 FIG. 2 shows a second embodiment of the present invention. In the second embodiment, the wiring pattern (1
This is a case where the number of 5) and the number of wiring channels (13) are the same.

In the second embodiment, all the wiring channels (13) formed between the lattices (11) are used, and the wiring pattern (15) is shifted on each wiring channel (13). It is a thing.

Embodiment 3 FIG. 3 shows a third embodiment of the present invention. In the third embodiment, the wiring pattern (1
The number of wiring channels (13) is equal to the number of wiring channels (13) where the number of wiring channels (13) is equal to the number of wiring channels (13) and the number (2) of wiring patterns (15) between grids (11). (3
This is a case where there are fewer parts (left part in the figure).

In the third embodiment, each wiring pattern (15) is arranged on three wiring channels (13) set in the right side (11) in the figure, and the wiring channel (13) is arranged in the left part in the figure. ), Another newly created wiring channel (16) is set, and the wiring pattern (15) is shifted on this other wiring channel (16).

Embodiment 4 FIG. 4 shows a fourth embodiment of the present invention. In the fourth embodiment, there is a case where there is a grid (11) without a land (14).

In the case of the fourth embodiment, one wiring pattern (1
5) passes over the grid (11) where there is no land (14), and is wired in a state where the first and second embodiments are combined. Therefore, in this case, the length of the wiring pattern (15) is longer than in the above embodiments.

(Effects of the Invention) As described in detail above, in the present invention, as illustrated in the above embodiment, "the wiring pattern (15) coming out of the land (14) is once put on the grid (11) and pulled out. At the intersection of the grid (11) and the wiring channel (13) formed between the land (14) from which the wiring pattern (15) has started and another land (14) adjacent thereto, the wiring pattern (15) is formed. ) Is bent at an angle of 45 ° with respect to the traveling direction, and furthermore, this wiring pattern (15) is placed on a newly formed wiring channel (13) between grids (11) passing through the wiring pattern (15). There is a feature in the structure of “being placed and bent”, whereby the wiring pattern can be routed more efficiently. Further, it is possible to provide a printed wiring board which can eliminate a problem such as a short circuit between wiring patterns that can achieve high-density mounting.

That is, in the printed wiring board (10) according to the present invention, since the conductor spacing can be increased, a short circuit, that is, a short circuit accident can be suppressed.

The above enables efficient wiring, so that the shape of the land (14) to which the wiring pattern (15) is not directly connected can be increased, and the number of small-diameter lands (14) difficult to manufacture and inspect is reduced. Can be reduced.

Because of the above-described advantages, the density of the printed wiring board (10) can be increased without sacrificing the production yield.

Since the diameter of the land (14) on both sides (all layers in the case of a multilayer board) of the printed wiring board (10) can be increased, the formation of the land (14) can be surely performed (so-called seat). Not only cuts) but also lands (1
The drilling step 4) can be facilitated, so that the cost of the printed wiring board (10) can be reduced.

As shown in FIG. 2, the wiring pattern (15a) which does not directly enter the land (14) bypasses the wiring pattern (15) which directly enters the land (14), thereby enabling one more wiring. In other words, the density can be increased.

Land (14) to which wiring pattern (15) is not directly connected
Since the shape of the printed wiring board (10) can be increased, the wiring pattern (15) in a certain sense can be shortened and crosstalk can be prevented, and the electrical characteristics and reliability of the printed wiring board (10) can be improved. it can.

[Brief description of the drawings]

FIG. 1 is a partially enlarged plan view of a printed wiring board according to the present invention, in which one wiring pattern is passed between lattices;
FIG. 2 is a partially enlarged plan view of a printed wiring board according to the present invention, in which two wiring patterns are passed between lattices;
3 and 4 are partial enlarged plan views corresponding to FIG. 1 showing another embodiment. FIG. 5 is a partially enlarged plan view of a printed wiring board showing a wiring state of a conventional wiring pattern. Explanation of reference numeral 10: printed wiring board, 11: grid, 12: intersection, 13:
... wiring channel, 14 ... land, 15 ... wiring pattern, 16 ... another wiring channel.

Claims (1)

(57) [Claims] 1. A land is formed on an intersection of a number of grids.
In a printed wiring board having two or more wiring channels between the grids and connecting the wiring patterns on the lands, the wiring patterns coming out of the lands are temporarily put on the grids and pulled out, and the wiring patterns are started. The wiring pattern is bent at an angle of 45 ° with respect to the traveling direction at the intersection of the grid and the wiring channel formed between the land and another land adjacent thereto, and further, the wiring pattern On a newly formed wiring channel in a required number between lattices passing therethrough and bent.