JPS6076185A - Printed plate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a printed board, and more particularly to the arrangement of wiring patterns on a printed board in which parallel wiring patterns are provided at high density.

・Technological background In multilayer printed circuit boards with high packaging density, in order to improve the packaging density of wiring patterns and simplify design and manufacturing, a wiring pattern is provided in one specific direction on one layer, and this pattern is placed on other layers. A method has been adopted in which a wiring pattern is provided in a direction that intersects with the directional line, and wiring between two predetermined points is performed by connecting the wiring pattern in one direction and the wiring pattern that intersects with the wiring pattern by through-hole plating or the like.

Figures 1 and 2 show an example of such a multilayer printed board, in which four-layer patterns B 2 , a + 2 b + 2 c, 2 are formed by three-layer substrates 1a+11++lc.
d is provided, and the pattern layer 2b includes electrolytic wires,
The pattern Jffi2c is provided with a ground wiring, and the patterns hVj2a and 2d are provided with signal wiring. The signal wiring is arranged in a pattern of: 42 as shown in Figure 2.
Wiring patterns 3a...3d in the X direction provided in a
. . . and Y-direction wiring patterns 4a, . An electrical connection is made between the desired two points. Here, 6...6 is a land, and wiring pattern 3
a...3d... and 4a...4n...
. is arranged so as to pass between the lands 6...6.

In order to further improve the packaging density of circuits on such printed boards, it becomes necessary to increase the number of wiring patterns arranged between lands.
It is designed so that three wiring patterns can be passed between the lands arranged at a pitch of 4 mm, instead of the conventional two. In this case, as the width of the wiring patterns arranged on the substrate becomes narrower, the intervals between the wiring patterns also naturally become narrower.

On the other hand, in electrical devices, there often arises a request to partially change a circuit that has been designed. Such requirements arise due to changes or improvements in the specifications of the device, and in rare cases arise due to design errors during circuit design or circuit implementation. If such a request arises after the printed board has been manufactured, the circuit is changed by cutting a portion of the wiring pattern and providing new connections using conducting wires.

The wiring pattern was first cut by removing the wiring pattern with the tip of a thin drill, but when three wiring patterns were passed between lands of 2.54 mm bi-1 inch. In this case, the spacing between wiring patterns becomes extremely narrow, making it extremely difficult to cut only one pattern with a drill. Therefore, attempts have been made to burn out the wiring pattern using a laser beam, but there is a problem that carbon remains after the pattern is burned out, causing a short circuit, so currently there is no other option than manually cutting out the desired wiring pattern. Therefore, if the mounting density of the printed circuit board wiring pattern is increased, extremely complicated work will be required when the circuit is changed after the printed board is manufactured, and this will cause the high density of the wiring pattern. This was a major cause of hesitation in density mounting.

・Purpose of the Invention This invention was made with the aim of making it possible to easily deal with circuit changes after manufacturing the printed circuit board, even in printed boards with high packaging density. The purpose of this invention is to provide a printed circuit board with high packaging density that can be easily implemented.

・Structure of the invention That is, the printed board of the present invention has a low pattern density between lands arranged parallel to the wiring patterns on the printed board on which a plurality of wiring patterns are provided parallel to each other between the lands. It is characterized in that the wiring patterns are bent as appropriate to widen the spacing between the plurality of wiring patterns at the V\ portion, and it becomes necessary to change the wiring no.F-turn after manufacturing the printed board. When the wire is bent, a desired wiring pattern can be cut at this bent portion with a +71 cut.

・Embodiment of the Invention Figure 3 shows an embodiment of the invention, and is 6...
・6 is a land, 7a...7 is a layout < turn, and 8 a + 8 C + 8 d + 8 f is a wiring node and is a bent part of turn 7 a + 7 c + 7 d + 7 f. Land 6 placed on the general printed board
...6G, the intervals are not all constant, and there is a part 9 where the opening force S between lands is wide, and in that part 9, naturally, the turn density is lower than 1, and the wiring pattern is bent. The portions 8a...8f are provided in this portion 9 where the pattern density is low. Wiring pattern 7a on the printed board...
The cause of 7f is often done using an automatic drawing machine, but in order to draw such bent portions 8a...8f of the wiring pattern using an automatic drawing machine, the wiring pattern 7a... ...When tracing 7f, check the interval between the wiring pattern being created and the adjacent pattern at predetermined intervals, and form a bent part of a predetermined shape where the interval is wide. The bent portion 8a...
- A wiring pattern having 8f can be drawn. If, for example, it becomes necessary to cut a certain wiring pattern 8a or 8b due to a circuit change, the corresponding wiring 1< turn is cut at %jl~min IQI+ sandwiched between this bending part 8a or bending parts 8a and 8c. If you do this, even if you pass three wiring no.tau turns between lands 6 and 6, you can remove the wiring pattern using a screwdriver, etc., just like in the case of the conventional two wires. Even in the case of a printed board with a high pattern density, it becomes possible to easily deal with circuit changes after the printed board is manufactured.

Note that when three wiring patterns are provided between lands provided at a pitch of 2.54 mm, the density of IC mounting on the printed board is approximately 1, compared to the case where two wiring patterns are provided. .It can be tripled. On the other hand, if you try to obtain the same packaging density with two wiring patterns between lands, you will have to use three or more signal line pattern layers, and the signal line pattern paste will have two layers. Not only does the cost required for the installation and production of the printed board significantly increase compared to the case where the wiring pattern of the signal line is also placed on the inner layer of the printed board,
It becomes increasingly difficult to deal with circuit changes.

・Effects of the Invention When the configuration of the present invention is adopted as described above, it becomes possible to easily cut the desired wiring pattern even in a printed board with high packaging density, so that the circuit after the printed board is manufactured can be easily cut. It is now possible to easily handle changes, so designers can proactively adopt high-density printed circuit boards that are fast and compact, and even in manufacturing sites, when changing the circuit of a printed circuit board. The excellent effect of reducing the workload can be obtained.

[Brief explanation of the drawing]

Figure 1 is a diagram showing an example of the laminated structure of a multilayer printed board.
FIG. 2 is a diagram showing a conventional arrangement of signal lines on a printed board, and FIG. 3 is a diagram showing an embodiment of the present invention. In the figure, 6 is a land, 7a7b... is a wiring pattern,
8a+8c... is a bent portion of the wiring pattern, and 9 is a portion where the land spacing is widened. Agent Patent Attorney Takao Nishi

Claims (1)

[Claims] (1) In a printed board in which a plurality of parallel wiring patterns are provided between lands, the spacing between the plurality of wiring patterns is widened in areas where the wiring density is low between the lands arranged parallel to the wiring patterns. A printed board characterized by having a wiring pattern bent as appropriate.