JP2617746B2 - Automatic wiring processing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Overview] In an automatic wiring processing method for a printed board in a computer-aided design such as CAD, the automatic wiring processing optimized for a partial area by recognizing a shape near a connection system to be wired. The purpose of this method is to make it possible to achieve a high automatic wiring ratio even on a printed circuit board with a high component mounting density. The first process of dividing by the above, the second process of obtaining the center of gravity of the land group of the focused partial area, and the center processing of the region, the obtaining of the center of gravity of the land group of the same connection system electrically connected in the partial area and connecting Processing as a system nucleus, processing for performing vector connection from the nucleus of the area and the nucleus of the connection system to each land, and the land group of the partial area and the land group of the same connection system in the target partial area A fifth process of evaluating the relative amount of effective wiring, a sixth process of evaluating the amount of intersection indicating the degree of overlap of the intersection region where the vector rectangular regions obtained by the vector connection of the region of interest overlap, A seventh process of selecting a region road having the smallest intersection amount as a candidate based on the evaluation of the intersection amount, an eighth process of dividing the wiring target into layers, and a process of forming a main line in the horizontal and vertical directions from the nucleus of the subsystem. A ninth process for connecting the main line horizontally or vertically to the main line, a tenth process for drawing the main line horizontally and vertically from the nucleus of the electrically connected region, and connecting the main line horizontally or vertically, and Assuming that the ninth and tenth processing results are processed and the eleventh processing of setting a wiring section having the minimum component capacitance is performed by using the processing result having a small wiring area in the horizontal and vertical directions and the sixth processing result. Configure.

[Industrial applications]

The present invention relates to a method for performing an automatic wiring process optimized for a partial area by recognizing a nearby shape of a connection system to be wired in a method for automatically wiring a printed board in a computer-aided design such as a CAD.

Due to the recent trend toward higher density of printed circuit boards, printed circuit boards with SMT mounted components (surface mounted components), and the aim of reducing costs by reducing the number of layers, wiring pattern densification is highly oriented. There is a need for an automatic routing method that takes into account a more regional viewpoint.

[Conventional technology]

Conventional automatic wiring methods include the following. This is an automatic wiring process for automatically determining the wiring path of the printed board by following the procedure shown in FIG.

Each step number in the following description corresponds to the step (ST) number described in FIG.

Step 310 The total number of printed boards and the effective wiring channel are defined, and the connection system having the same potential is decomposed into the wire segments by decomposing the shortest solution path.

Step 320 A wiring route is obtained by a line search process using x and y of the own system to be connected.

Step 330 The connection route of the section of the wire is found and the route is determined. When a route is determined, channels are allocated according to the order of use of the channels.

Step 340: Determine whether the capacity of the channel in the connection section is capable of automatic wiring processing, and if the wiring is possible, continue the automatic wiring processing. If the capacity of the channel is insufficient, proceed to the next step.

Step 350 Manual wiring is performed at a place where automatic wiring processing is impossible, and the wiring processing of the printed board is completed.

[Problems to be solved and used by the invention]

By the way, in the above-mentioned conventional automatic wiring processing method, based on the fixed channel, the channel is assigned by the shortest path length of two points with respect to the channel for each net of the connection system, and the wiring route is determined. And these are made up of their own systems. For this reason, since the influence of other connection systems in a certain area and the effective use of the relative area for the automatic wiring processing are not taken into consideration, the order of the automatic wiring processing greatly affects the usage of the area. ing. That is, the later the wiring process, the smaller the area that can be wired, the more difficult the automatic wiring process becomes, the lower the automatic wiring ratio becomes, and especially the higher the mounting density on the printed board becomes, the higher the automatic wiring ratio becomes. Is low.

Accordingly, an object of the present invention is to provide an automatic wiring processing method that can achieve a high automatic wiring ratio even on a printed board having a high component mounting density.

[Means for solving the problem]

In the present invention, a means for solving the above problem is an automatic wiring processing method characterized in that a route to be wired is determined by the following processing.

(A) First processing for dividing a wiring target area based on a predetermined reference.

(B) a second process in which the center of gravity of the land group of the focused partial region is determined and the center of the region is determined, and (C) the center of gravity of the land group of the same connection system electrically connected in the partial region is determined. Third process as a core.

(D) Fourth processing for performing vector connection from the nucleus of the region and the nucleus of the connection system to each land, and (E) Effectiveness of the land group of the partial region and the land group of the same connection system in the focused partial region Fifth processing for evaluating the relative amount of wiring.

(F) Sixth processing for evaluating the amount of intersection indicating the degree of overlap of the intersection area where the vector rectangular areas obtained by the vector connection of the attention area overlap.

(G) A seventh process of selecting, as a candidate, an area road having the minimum intersection amount based on the evaluation of the intersection amount.

(H) Eighth process for dividing the wiring target layer.

(I) Ninth processing for drawing a main line in the horizontal and vertical directions from the core of the subsystem and connecting the main line to the main line horizontally or vertically.

(J) Tenth processing for drawing a main line in the horizontal and vertical directions from the nucleus of the electrically connected area and connecting the main line horizontally or vertically.

(K) An eleventh process in which the ninth and tenth processing results are processed, and the processing result with a small horizontal and vertical wiring area and the sixth processing result are used to set the minimum component capacity wiring section.

[Action]

According to the present invention, the intersection amount indicating the degree of overlap of the intersection region where the vector rectangular region obtained by the vector connection of the attention region overlaps is evaluated, and the intersection amount is minimized based on the evaluation of the intersection amount. Automatic routing is performed based on the evaluation of wiring based on intersections at vector rectangles that select area roads as candidates and the evaluation of wiring based on horizontal and vertical trunk lines from lands. Not only the other net systems are considered, but also a high automatic design ratio can be achieved regardless of the order of the wiring processing.

〔Example〕

An embodiment of the automatic wiring processing method according to the present invention will be described below with reference to the drawings. 2 to 4 show an embodiment of the automatic wiring processing method according to the present invention. This embodiment operates according to the flowchart shown in FIG.

In this embodiment, the processing of (H) to (J) is performed first, and then the processing of (F) and (G) is performed after the processing of (A) to (E) described in the means for solving the above problem. And finally the processing of (K) is performed.

Step 10: Function division processing of the printed board: The whole is divided into several partial areas by shape similarity processing (corresponding to (A) of the means for solving the above problem).

Step 20 As pre-processing, a region having a high similarity in shape and a random region having a low similarity in shape are divided into a region having a high similarity based on the component arrangement and the connection relationship. The nucleus is obtained by the centroid method, and this nucleus is used as the kernel of the partial region (corresponding to (B)).

Step 30 The nucleus of the system of electrically connected lands in the region is determined by the centroid method, and this nucleus is used as the kernel of the connection system (corresponding to (C)).

Step 40 Output a vector from the kernel of the region to the land of the electrically connected system, and output a vector from the kernel of the connected system to the land of the electrically connected system, and perform the respective vector connection processing. (Equivalent to (D)).

Step 50 The occupancy of the partial area is evaluated relative to the horizontal and vertical components,
The wirable area is recognized by a state function using the cross point, the via, the wiring route segment in the horizontal and vertical directions, and the wiring capacity as parameters, and this is defined as a background effective wirable area (corresponding to (E)).

Step 60 The wiring layer is separated from the kernel having a tilt in the + direction and the one having a tilt in the-direction, for example, according to the inclination between the kernel generated in the region of interest and the land system electrically connected to the wiring layer. A division process is performed (corresponding to (H)).

Step 70 Connection processing is preferentially performed on a system in which the lands are located in the same direction, that is, in the horizontal or vertical direction, in the system subjected to the layer division processing.

Step 80 A trunk line is drawn horizontally and vertically from the kernel of the connection system that has been electrically connected, and a horizontal or vertical connection process from the land to the trunk line is performed (corresponding to (J)).

Step 90 The evaluation processing of the area occupied area of the wiring processed in step 80 is performed (corresponding to the processing of the ninth processing result in the former stage of (I)). This is performed by projecting the connections subjected to the connection processing in the horizontal and vertical directions as shown in FIG. 3 and evaluating the degree of overlap.

Step 100: A main line is drawn in the horizontal and vertical directions from the kernel of the area system, and a connection process is performed horizontally and vertically to the main line ((I)).
Equivalent).

Step 110 The processing of evaluating the area occupancy component of the wiring processed in step 100 is performed (corresponding to the preceding step 10 in the same (K)). This is a process similar to step 90.

Step 120 The area occupied part of the wiring processed in step 80 and the step
The area having the smaller wiring amount is compared with the area occupied portion processed in step 100, and the smaller wiring amount is set as an object of the automatic wiring processing (corresponding to the former stage of the same (K)).

In step 130, an intersection evaluation is performed to evaluate the amount of intersection indicating the degree of overlap of the intersection area where each of the rectangular areas having the two corners with the vector obtained in step 40 for the area obtained in step 120 in the area of interest. )).

Step 140 Based on the evaluation of the amount of intersection, an area route having the minimum amount of intersection is selected as a candidate (corresponding to (G)), and a route that can be taken by a wiring is extracted as an envelope in the rectangular area based on the above-mentioned intersection evaluation. , And determines a direction conversion wiring path (corresponding to (K)).

Step 150 After the above processing, a wiring process for re-routing the right-angled portion of the wiring at an oblique angle of 45 °, a correction process such as a detour process due to an expansion of the wiring region caused by insufficient capacity of the background region, and the like are performed.

Processing is performed by using a parameter that has priority so that wiring processing is performed in a wiring section having a smaller number of direction change points in an envelope formed by connecting the contours of the intersection area roads generated by the intersection evaluation with the wiring roads. In addition, the correction conditions are corrected based on the selection conditions for the case where the intersection has occurred and the case where the detour has been made, using values set in advance by using parameters.

Next, a case where wiring is actually performed by the automatic wiring processing method according to the present embodiment will be described. FIG. 3 shows an example in which automatic wiring is performed by the automatic wiring processing method according to the above-described embodiment. In FIG. 3, symbols ln1 to ln6
Indicates a land to be wired. Then, the nucleus SKNL of the region and the nucleus CKNL of the connection system are obtained from these lands ln1 to ln6, and vector connections are made to these (thin lines and broken lines in FIG. 3). (In this example, the nucleus of the region is selected.) Further, correction is made to reduce the occurrence of vias (VIA). As shown in the table below, the horizontal and vertical directions of the wiring and the overall occupancy ratio are different from those in the case where the automatic wiring processing method shown in FIG. The number of vias is also small.

As described above, each component is greatly reduced, and it can be seen that the automatic wiring can be efficiently implemented according to this embodiment.

〔The invention's effect〕

As described above, according to the present invention, the intersection amount indicating the degree of overlap of the intersection region where the vector rectangular region obtained by the vector connection of the attention region overlaps is evaluated, and based on the evaluation of the intersection amount, Automatic wiring is performed based on the evaluation of wiring by intersection at a vector rectangle that selects the area road with the smallest amount of intersection as a candidate and the evaluation of wiring based on horizontal and vertical backbone lines from lands, so efficient Automatic wiring can be performed. That is, since a random relative automatic wiring method is adopted in consideration of a net system having a connection relationship between the same connection system and the attention area, unnecessary capacity can be reduced, and the occurrence of vias can be minimized. It is also possible to improve the automatic wiring rate of the density wiring processing, and to prevent the useless via from being generated.

[Brief description of the drawings]

FIG. 1 is a principle diagram of the present invention, FIG. 2 is a flowchart showing an embodiment of an automatic wiring processing method according to the present invention, and FIG. 3 is an example of automatic wiring processing by the automatic wiring processing method shown in FIG. FIG. 4 is a diagram showing a third example of the conventional automatic wiring processing method.
FIG. 5 is a flow chart showing a conventional automatic wiring processing method.

Claims (1)

(57) [Claims] 1. An automatic wiring processing method, wherein a route to be wired is determined by the following processing. (A) First processing for dividing a wiring target area based on a predetermined reference. (B) A second process in which the center of gravity of the land group of the focused partial region is determined and used as the core of the region. (C) Third processing for determining the center of gravity of a group of lands of the same connection system electrically connected in the partial area and using the lands as the core of the connection system. (D) Fourth processing for performing vector connection from the nucleus of the region and the nucleus of the connection system to the land, respectively. (E) Fifth processing for evaluating the relative amount of effective wiring between the land group of the partial area and the land group of the same connection system in the partial area of interest. (F) Sixth processing for evaluating the amount of intersection indicating the degree of overlap of the intersection area where the vector rectangular areas obtained by the vector connection of the attention area overlap. (G) A seventh process of selecting, as a candidate, an area road having the minimum intersection amount based on the evaluation of the intersection amount. (H) Eighth process of dividing the wiring target into layers. (I) Ninth processing for drawing a main line in the horizontal and vertical directions from the core of the subsystem and connecting the main line to the main line horizontally or vertically. (J) Tenth processing for drawing a main line in the horizontal and vertical directions from the nucleus of the electrically connected area and connecting the main line horizontally or vertically. (K) An eleventh process in which the ninth and tenth processing results are processed, and the processing result with a small horizontal and vertical wiring area and the sixth processing result are used to set the minimum component capacity wiring section.