JPH0677321A - Automatic wiring method - Google Patents

Abstract

PURPOSE:To improve the quality of wiring by the use of wiring in a sub-axis direction at the time of the automatic wiring of an integrated circuit and a printed board. CONSTITUTION:In an automatic wiring method for a multilayer wiring area of an integrated circuit and a printed board, when wiring is permitted, for each wiring layer, in two directions; namely, a main axis direction which is a major wiring direction and a sub-axis direction that is orthogonal to the main axis direction, an escape line for avoiding an obstacle in the main axis direction and a sub-escape line for avoiding the obstacle in the sub-axis direction are created around the obstacle (step A). A search line is created from a terminal to find an escape line which crosses the search line in a position where a through-hole can be opened, and to find a sub-escape line which crosses the search line on the same wiring layer as the search line. The escape and sub- escape lines thus found are utilized as new search lines. This search is iterated to find wiring routes until it reaches a search line created from a target terminal (steps B, C, D, E and H).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic wiring system for integrated circuits and printed circuit boards.

[0002]

2. Description of the Related Art As a conventional automatic wiring system, a corner point is generated at a position separated from a corner of an obstacle by a distance satisfying a design rule in a wiring area having a multilayer structure, and the corner point is used as a reference. There is a line segment search method for generating an escape line for avoiding an obstacle and finding a wiring route from these escape lines (Japanese Patent Laid-Open No. 3-127852).

[0003]

In the conventional line segment search method using the escape line, only the wiring in the main axis direction is allowed, and when the wiring route bends, a through hole is always hit and the line is moved to the adjacent layer once. From there, I had no choice but to turn to a wiring path that bends sideways. However, in the case of just moving the wiring path to a few columns next to it, moving through to the adjacent layer and then returning to the original layer would result in too many through holes. As a result, the wiring area is wasted and the quality of the wiring is degraded.

The object of the present invention is to solve the above-mentioned drawbacks and to provide an automatic wiring system with few through holes and good wiring quality.

[0005]

An automatic wiring system according to the present invention is an automatic wiring system in a multi-layer wiring region of an integrated circuit or a printed circuit board, which is a main wiring direction for each wiring layer and is orthogonal to the main axis direction. When wiring in two directions along the minor axis is allowed, a corner point is generated at a position that is away from the corner of the obstacle included in the wiring area by a distance that satisfies the design rule, and passes through the corner point. An escape line for avoiding obstacles in the main axis direction and a sub escape line for avoiding obstacles in the sub-axis direction passing through the corner points are generated, and a search line is generated from the terminal to be wired, and a through hole is generated. The escape line that intersects the search line at a position where it can be hit and the sub-escape line that intersects the search line in the same wiring layer. Searching for the escape line and the sub escape line as a new search line, and repeating the search until the search line generated from the target terminal is reached to search the wiring route. Characterize.

[0006]

According to the present invention, in the automatic wiring process of the integrated circuit or the printed circuit board, when the wiring in each of the wiring layers is permitted in the two directions of the main axis direction which is the main wiring direction and the sub-axis direction orthogonal to the main axis direction. , An escape line that generates a corner point at a distance from the corner of the obstacle included in the wiring area that satisfies the design rule, and avoids the obstacle in the main axis direction through the corner point. A sub that avoids obstacles in the sub-axis direction through points
An escape line is generated, a search line is generated from the wiring target terminal, and an escape line that intersects with the search line at a position where a through hole can be formed and a sub that intersects with the search line in the same wiring layer -Search for escape lines, use those escape lines or sub escape lines as new search lines, and repeat this search until the new search line generated from the target terminal is reached. This enables wiring in the sub-axis direction. As a result, in the case of a wiring path that goes to an adjacent layer and returns immediately, it is possible to reduce the number of through holes and improve the wiring quality by wiring in the sub-axis direction while keeping the same layer. Become.

[0007]

EXAMPLES The automatic wiring system of the present invention will be described in detail with reference to examples.

FIG. 5 is a flow chart showing the processing method of the present invention. A detailed description will be given below along this flowchart.

FIG. 1 shows a corner point 15 and an escape line 1 around an obstacle 11 in a two-layer wiring area.
3 shows a situation in which the sub escape line 14 is generated. The corner point 15 is generated at a position separated from the corner of the obstacle 11 by the allowable range of the design rule. Next, when the line is extended from the corner point 15 in the main axis direction, which is the main wiring direction of the wiring layer, the line is extended from the obstacle 11 which first hits to a position separated by the allowable range of the design rule, and escaped. Set to line 13. Next, a line is slightly extended from the corner point 15 in the sub-axis direction orthogonal to the main-axis direction to form the sub-escape line 14. The length to extend the sub-escape line 14 is arbitrary, but if the wiring in the sub-axis direction is too long, it interferes with the wiring in the main-axis direction. Therefore, in consideration of this, select an appropriate length. .
(Step A) FIG. 2 shows a state in which the search for the wiring route is started. First, a search line 21 is generated from the source and target terminals 12. This is a search line 21 by extending a line from the point having the same coordinates on the layer where the terminal exists and the layer adjacent to the terminal to a point separated from the obstacle by the allowable range of the design rule along the main axis direction of the layer. To do. Then, an escape line 13 that intersects the search line 21 generated from the source terminal 12 at a position where a through hole can be formed, and a sub-escape line 14 that intersects the search line 21 in the same wiring layer are provided. A new search line 21 is searched for. Then, the operation of searching for the escape line 13 and the sub-escape line 14 that intersect the search lines 21 is repeated until the search line generated from the terminal 12 of the target is reached. (Steps B, C, D, E, H) FIG. 3 shows a place where the wiring route is found after the search by the search line is completed. In this case, only one place selects the sub-escape line 14 in the sub-axis direction as the wiring path. Then, the escape line 13 and the sub-escape line 14 are reversed from the terminal 12 of the target.
The wiring route is determined by tracing.

FIG. 4 shows a situation in which the wiring route is completed. In this case, it is necessary to place a through hole in the portion where the wiring in the main axis direction of the adjacent layer intersects, but it is not necessary to place the through hole in the portion where the wiring in the auxiliary axis direction and the wiring in the main axis direction are used. (Steps F and G)

According to the present invention, wiring in the sub-axis direction is possible, and in the case of a wiring route that goes to an adjacent layer and returns immediately, it is possible to perform wiring by wiring in the sub-axis direction in the same layer. This has the effect of reducing the number of holes and improving the quality of wiring.

[Brief description of drawings]

FIG. 1 is a diagram showing how wiring is preprocessed.

FIG. 2 is a diagram showing a situation in which a search for a wiring route has started.

FIG. 3 is a view showing a place where a wiring route is found.

FIG. 4 is a diagram showing a state in which a newly found wiring path is completed.

FIG. 5 is a flowchart showing a processing flow of the present invention.

[Explanation of symbols]

 11 Obstacle 12 Terminal 13 Escape Line 14 Sub Escape Line 15 Corner Point 21 Search Line 41 Through Hole 42 Wiring Route

Claims (1)

[Claims] 1. In an automatic wiring system in a multilayer wiring area of an integrated circuit or a printed circuit board, when wiring in two directions, a main axis direction which is a main wiring direction and a sub-axis direction orthogonal to the main wiring direction, is permitted for each wiring layer. , A corner point is generated at a position away from the corner of the obstacle included in the wiring area by a distance satisfying the design rule,
Generate an escape line that avoids obstacles in the main axis direction through the corner points and a sub escape line that avoids obstacles in the minor axis direction through the corner points, and search lines from the terminals to be wired. The escape line that is generated and crosses the search line at a position where a through hole can be hit and the sub-escape line that crosses the search line in the same wiring layer are searched for, Escape line and the sub
An automatic wiring method that uses the escape line as a new search line and repeats this search until the search line generated from the target terminal is reached to search the wiring route.