JP3208014B2 - Wiring path inspection device and wiring path inspection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring path inspection apparatus and a wiring path suitable for a layout design of a semiconductor device.
Investigation method .

[0002]

2. Description of the Related Art In a process of designing a layout of a semiconductor device, that is, a process of generating a layout drawing, a layout of wiring to be provided in the semiconductor device is determined. At this time, a problem of how to connect desired terminals (parts to be connected by wiring) within a predetermined wiring area by wiring.
That is, the wiring problem must be solved. VLSI
With the recent increase in the size of semiconductor devices such as (ultra-large-scale integrated circuits), the ratio of wiring in the wiring area has increased remarkably, so that the wiring problem has become increasingly difficult to solve. It is becoming something.

The wiring problem can be regarded as a generalized and abstracted problem as follows. First, a wiring problem is defined as a problem in which terminals arranged in a region of one or more layers are connected by wires. Here, the term “terminal” is a concept defined as a set of one or more points in a region. Each layer of the region is conceptually divided into a plurality of small regions by line segments. This small area is called a "grid". Each terminal is given a kind of identification name called "net name", only terminals having the same net name must be connected to each other by lines, and terminals having different net names must be connected by lines. Connecting (this is called a "short circuit") is not allowed. And when two lines occupy the same grid,
These lines are considered to be connected to each other.

[0004] From each grid, it is permissible to draw a line to a grid that contacts the grid (except for a grid that contacts only one point). It is also permitted to draw lines on the grid directly above and below the grid located on the layer next to the grid. However, it is not allowed to draw lines on other grids without passing through other grids. There is no limit on the number of terminals having the same net name. In the following, a line is drawn to connect terminals, and any of the drawn lines is referred to as “wiring”. The net name of the wiring is defined by the net name of the terminal connected to the wiring.

[0005] As the ratio of wiring occupying the wiring area increases, it becomes difficult to find an appropriate route for wiring. This is why the wiring problem is becoming increasingly difficult to solve as described above. For this reason, a wiring route inspection device that finds an appropriate route with a high possibility has become one of the indispensable design tools for the layout design of a semiconductor device in recent years.

Before describing the configuration of a conventional wiring route inspection apparatus, its operation will be described along an example of a wiring problem. FIG. 10 is a schematic diagram illustrating an example of a wiring problem. In the following, regarding the schematic diagram of FIG. 10 as an example, the right side is “east”, the left side is “west”, and 90 degrees counterclockwise from east.
The direction rotated by "degree" is "north", the opposite direction is "south", the upward direction perpendicular to the drawing (the direction toward the front of the paper) is "up", and the downward direction perpendicular to the drawing (the depth of the paper) Direction) is referred to as “down”.

The wiring problem shown in FIG. 10 is an example of a one-layer wiring problem. In FIG. 10, a small rectangular area separated by a thin line represents one grid, black circles represent terminals, and hatching represents obstacles. In this example, all terminals consist of one point. Symbols A, B, and C are all net names. As described above, the wiring problem is to connect all terminals having the same net name by wiring.

FIG. 11 is a schematic diagram showing a state where two terminals of the net B and two terminals of the net C are connected first by the shortest path. After this state, the process of connecting the remaining two terminals of the net A by wiring must be continued. However,
The already drawn wirings (hereinafter, referred to as “previously-wired”) hinder the connection of the two terminals of the net A without peeling or moving these already-drawn wirings.

In this case, a process is first performed in which a path that causes a short circuit is found, and an existing wiring sharing a grid with the path is moved. For example, by first finding the path indicated by the broken line p in the schematic diagram of FIG. 12 and moving the existing wiring of the net C, appropriate wiring as shown in the schematic diagram of FIG. 13 is realized, and this wiring problem is solved. You.

FIG. 14 is a block diagram showing a configuration of a conventional wiring route inspection device for searching for a wiring route. In FIG. 14, the already-wiring-pattern storage unit 1 is a storage device such as a memory, and includes information on already-wiring illustrated in FIG. 11, that is, data on which grid is drawn from which grid to which grid is drawn. I remember. The terminal information storage unit 2 is another storage device such as a memory, and stores information of a terminal to be connected, that is, a terminal position and a net name.

[0011] The input processing unit 3 includes an already-wiring-pattern storage unit 1
Is received via a signal line 101, and information on a terminal to be connected is received from a terminal information storage unit 2 via a signal line 102. The input processing unit 3 transfers the information to the wiring route searching unit 4 via the signal line 103.

The wiring route search unit 4 receives the information and searches for a route connecting the terminals using a well-known maze method. Then, a path that minimizes a predetermined function called a cost function is found. This operation will be described using a process of searching for a route connecting two terminals having the same net name as an example. In this case, usually, one of the following two cost functions is used.

Cost function 1 = (path length) + (constant) ×
(Number of short-circuits): Here, the path length is the length of the path when the interval between adjacent grids is "1", and the constant is a positive number and a number considerably larger than "1". Yes, and the number of short-circuits is the number of grids that are shared by a route and a route having a net name different from the net name of the terminal to be connected. Using this cost function 1, a path q is found as a path connecting the two terminals of the net A shown in FIG.
At this time, the number of short circuits is two.

Cost function 2 = (path length) + (constant 1) ×
(Number of contacts) + (constant 2) × (number of intersections): Here, the path length is the same as the above-mentioned path length, constant 1 is a positive number, constant 2 is a number larger than constant 1, In addition, the number of contacts has a net name different from the net name of the terminal to be connected The number of grids where the route and the route contact, and the number of intersections has a net name different from the net name of the terminal to be connected This is the number of grids where the existing wiring and the route intersect.

When the cost function 2 is used, a route p or a route r is found as a route connecting the two terminals of the net A shown in FIG. At this time, the number of contacts is 3 and the number of intersections is 0 in both routes. On the other hand, since the number of contacts is 0 and the number of intersections is 2 in the route q, the route q
Is not found.

The wiring route search unit 4 sends information on the found routes, that is, data on which grids pass through which grids to which grids, by the signal line 10.
4 to the output processing unit 5. The output processing unit 5
While receiving the route information, the information is transferred to the wiring route search result storage unit 6 via the signal line 105. The wiring route search result storage unit 6 is a storage device such as another memory, and stores the transferred route information.

In order to finally determine all the wirings based on the paths searched in the above manner in the wiring path inspection device, post-processing such as removal of the existing wirings is required. FIG. 15 is a block diagram showing an entire configuration of a wiring device, that is, a device for determining wiring. As shown in FIG. 15, the wiring device 300 includes the wiring route inspection device 30 described above.
1 as a component.

In the wiring device 300, a route is first found by the wiring route inspection device 301. Next, if an existing wiring located on the found path exists, the existing wiring is removed by the existing wiring removing device 302. Then, in the wiring determination device 303, the wiring is drawn along the found path and becomes one of the existing wirings. Control unit 304
Then, it is determined whether or not there is a removed wiring, and if so, the wiring route inspection device 301 is started again to redraw the removed wiring. vice versa,
If there is no removed wiring, the wiring is determined. Note that the control unit 304 also has a function of controlling the operations of the wiring route investigation device 301, the already-existing wiring removal device 302, and the wiring determination device 303.

As is clear from the above description of the wiring device 300, the wiring route inspection device 301 plays a major part in a series of processes in the wiring device 300.

[0020]

By the way, in the conventional wiring route inspection apparatus, taking the wiring problem shown in the schematic diagram of FIG. 10 as an example, as described above, as a route connecting two terminals of the net A, Whether the route q shown in FIG. 12 is found,
Or both path p and path r are found. However, the path p is appropriate as a path connecting the two terminals of the net A. This is because if the already routed net C is shifted in the east direction, the two terminals of the net A can be connected by the route p as shown in FIG. 13, while the already routed net B is shifted in the wiring area. For you cannot do it.

Here, "to shift" an existing wiring in a certain direction means to perform an operation of moving one wiring line in that direction while maintaining the connection between the terminals and without causing a short circuit. One or more times. At this time, for one or both of the endpoints of this line segment,
Line segments connecting the grids before and after the movement may be newly added or deleted.

As described above, in the conventional wiring route inspection apparatus, it may not be possible to find an appropriate route, and as can be understood from the description using the schematic diagram of FIG. As the ratio of the occupied wirings, that is, the density of the wirings, increases, the number of paths having a short circuit, contact, or intersection with the existing wirings increases, and as a result, it is difficult to find an appropriate path. This means that, when a layout design of a large-scale semiconductor device in recent years is performed, it is difficult to find a route even when using a wiring route inspection device.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a wiring route inspection apparatus and a wiring route inspection method capable of finding an appropriate route with a higher possibility even when the wiring density is high. The purpose is to provide.

[0024]

According to a first aspect of the present invention, there is provided a wiring route searching apparatus for connecting a given plurality of terminals in a wiring area which is conceptually divided into small areas by line segments. In a wiring path surveying apparatus for searching for a wiring path to be connected by sequentially following the small area, it is determined whether or not the small area can be opened with respect to the small area where the existing wiring exists, that is, the connection between the terminals. To determine whether it is possible to move the existing wiring in the small area to the outside of the small area without causing a short circuit with another existing wiring while maintaining the same. Research means;
Wiring route searching means for searching for a wiring route based on the result of the judgment by the already-moved wiring possibility investigating means.

According to a second aspect of the present invention, there is provided the wiring route inspection apparatus according to the first aspect, wherein the already-wired-movability investigating means clears a small area where the already-wiring exists. The determination as to whether or not it can be made is made between another small area adjacent to the small area to be determined and passing through the adjacent boundary from another small area to be determined as the determination target. It is characterized in that it is performed according to whether or not there is a route of a wiring without passing through a small area.

According to a third aspect of the present invention, in the wiring route inspection apparatus according to the first aspect of the present invention, the already-moved wiring possibility investigating means may open a small area where the already-existing wiring exists. It is characterized in that the determination as to whether or not it is possible is made in consideration of the possibility of movement of another existing wiring which is an obstacle in moving the existing wiring out of the small area.

[0027] According to a fourth aspect of the present invention, in the wiring route inspection apparatus according to the first aspect, the already-routed wiring possibility investigating means may open a small area where the already-routed wiring exists. It is possible to determine whether or not it is possible to move a fixed line segment existing on the small area while configuring the existing wiring in parallel to the outside of the small area while maintaining connection with other parts. In addition to this, it is further performed in consideration of the possibility of movement of another existing wiring which becomes an obstacle in moving the line segment out of the small area in parallel.

According to a fifth aspect of the present invention, in the wiring route inspection apparatus according to the first aspect of the present invention, the already-moved wiring possibility investigating means may open a small area where the already-existing wiring exists. The determination as to whether or not it can be made is made between another small area adjacent to the small area to be determined and passing through the adjacent boundary from another small area to be determined as the determination target. A first mobility possibility investigating means for determining whether or not a small wiring path exists without passing through a small area, and determining whether or not the small area in which the existing wiring exists can be opened; Is determined according to whether or not a fixed line segment that constitutes the existing wiring and exists on the small area can be moved in parallel to the outside of the small area while maintaining the connection with other parts. And, further, the line segment is And second movement possibility investigating means for taking into account the movement possibility of another existing wiring which becomes an obstacle in moving the wiring parallel to the outside. In any case, when it is determined that the small area can be vacated, it is determined that the small area can be vacated. The invention
The wiring route inspection method according to claim 6 according to
More conceptually, within a wiring area divided into small areas,
By sequentially following the small area between the plurality of terminals.
Route survey method to search for the route of the interconnect to connect
The small area where the wiring already exists.
Whether the connection between the terminals
Do not short-circuit with other existing wiring while maintaining
The existing wiring existing in the small area is moved out of the small area.
It is possible to move the existing wiring to determine whether it can be moved
Performance investigation process and the existing wiring movement possibility investigation process
Based on the result of the judgment, the route
And a road search step.

[0029]

In the wiring route inspection apparatus according to the first aspect, the wiring is determined by taking into account the judgment of the existing wiring movement possibility investigating means, that is, the judgment of whether or not the small area where the existing wiring exists can be opened. Route is searched, so that the best route is found with high probability.

In the wiring route inspection apparatus according to the second aspect,
It is determined whether or not the small area where the existing wiring exists can be separated by determining whether another wiring in which the wiring comes from the small area to be determined is adjacent to the small area to be determined and passes through the adjacent boundary. The determination is made according to whether or not there is a route of a wiring that does not pass between small areas without passing through the small area to be determined. That is, the determination as to whether or not the small area can be opened depends on whether or not the existing wiring existing on the small area can be shifted, that is, connecting a certain line segment constituting the existing wiring to another part. Is not limited to the determination as to whether or not the movement can be performed in parallel while maintaining the above, and in this regard, a determination closer to reality is made.

In the wiring route inspection apparatus according to the third aspect,
The determination as to whether or not the small area in which the existing wiring exists can be made in consideration of the possibility of movement of another existing wiring that is an obstacle in moving the existing wiring out of the small area. That is, even if there is an existing wiring that is an obstacle, it does not directly lead to the determination that the small area cannot be opened. Even if there is existing wiring that is an obstacle, if it can be moved,
In reality, a small area can be opened. Therefore, in the wiring route inspection device, a determination reflecting the reality is performed.

In the wiring route inspection apparatus according to the fourth aspect,
Since it is determined whether or not the small area where the existing wiring exists can be opened by shifting the existing wiring, the determination is easily performed. Moreover, by taking into account the possibility of movement of other existing wiring that is an obstacle in shifting the existing wiring,
Judgments are made that better reflect reality.

In the wiring route inspection apparatus according to the fifth aspect,
In the first mobility possibility investigating means, it is determined whether or not the small area can be opened by determining whether the wiring is started from the small area which is adjacent to the small area to be determined and passes through the adjacent boundary. This is performed depending on whether or not there is a route of a wiring that does not pass through another small area described above without passing through the small area to be determined. That is, the determination as to whether or not the small area can be opened is made by shifting the existing wiring existing on the small area, that is, parallelizing a certain line segment constituting the existing wiring while maintaining the connection with other parts. The invention is not limited to the determination as to whether or not it can be moved.

Further, the second movement possibility investigating means determines whether or not the small area where the existing wiring exists can be opened by shifting the existing wiring. A determination is made in consideration of the possibility of movement of another existing wiring that becomes an obstacle. The means for investigating the possibility of moving existing wiring
Since the judgment result by the two movable possibility investigating means is a logical sum of the judgment results, a proper judgment result can be obtained even if it is judged that only one of them can clear the small area. Can be Claim
In the wiring route survey method described in Item 6, the possibility of moving the existing wiring
Judgment of the inspection process, that is, empty the small area where the existing wiring exists
By taking into account the judgment of whether
And the route of the wiring is searched,
Found with the ability.

[0035]

【Example】

First Embodiment First, a description will be given of a wiring route inspection apparatus according to a first embodiment. FIG. 1 is a block diagram showing the configuration of the wiring route inspection device of this embodiment. In the following drawings, the same parts as those of the conventional device shown in FIG. 14 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, reference numeral 13 denotes an input processing unit, 14 denotes a wiring route searching unit, 15 denotes an already-movable wiring possibility investigating unit, and 113 to 116 denote signal lines.

The already-wiring-pattern storage unit 1 stores information of already-wiring, and the terminal information storage unit 2 stores information of terminals to be connected. The input processing unit 13 receives the information of the existing wiring stored in the existing wiring pattern storage unit 1 via the signal line 101, and
Is received via the signal line 102. The input processing unit 3 further transfers these pieces of information to the wiring route searching unit 14 via the signal line 113, and transfers the information of the already-wired to the already-moved wiring possibility investigating unit 15 via the signal line 114.

The wiring route searching unit 14 receives the information of the already-wired wiring and the information of the terminal to be connected, and finds a route connecting the terminals by using a maze method. At this time, a path that minimizes the following cost function is found.

Cost function 3 = (path length) + (constant 1) ×
(Number of short circuits that can be removed) + (constant 2) × (number of short circuits that cannot be removed): Here, the path length is a path in which the interval between grids adjacent in any of the vertical directions of east, west, north and south is “1”. And the constant 1 is a preset numerical value,
Moreover, it is a positive number considerably smaller than "1". Also,
The constant 2 is a positive number that is set to a value much larger than "1", and the number of short-circuits that can be removed is shared by the route and the route that has a net name different from the net name of the terminal to be connected. Of the grids to be connected, the number of grids determined to be vacant by the already-wired-movability investigating unit 15 is the number of grids that cannot be removed. This is the number of grids that are determined by the already-routed wiring possibility investigating unit 15 to be unable to be vacated among the grids shared by the routed route and the route having.

Here, "to open the grid" means to remove the existing wiring on the grid by moving the existing wiring without causing a short circuit while maintaining the connection between the terminals. Also, constant 1 and constant 2
Include, for example, about 0.1 to 0.5, and 1
A value of about 00 to 1000 is given.

In order to find a route that minimizes the cost function 3 described above, it is necessary to determine whether or not each grid on which an existing wiring exists can be opened. The already-movable-wiring-movability investigating unit 15 is provided to make this determination. Wiring route search unit 14
Sequentially transfers the coordinates of the grid requiring this determination to the already-movable-movability investigating unit 15 via the signal line 115.

The already-wired-movability investigating unit 15 receives the already-wired information transferred from the input processing unit 13. Upon receiving the coordinates of the grid where the existing wiring exists from the wiring route searching unit 14, the already-moved wiring possibility investigating unit 15 checks whether or not the grid can be opened. More specifically, a route that does not pass through the terminals connected by the existing wiring on the grid, neither on the grid nor on the grid occupied by the existing wiring having a net name different from the existing wiring. Whether or not they can be connected is checked using a maze method.

When the connection can be made, it is determined that the connection can be made empty. On the contrary, when the connection cannot be made, it is determined that the connection cannot be made free. If it is determined that the space can be opened, the information that the space can be opened is transferred to the wiring route search unit 14 via the signal line 116. Conversely, if it is determined that the space cannot be opened, the space can be opened. Information that there is no information is transferred.

The wiring route searching section 14 receives the information transferred from the already-movable wiring possibility investigating section 15, that is, information on whether or not the wiring can be vacated. That is, in order to find a route that minimizes the cost function 3, the wiring route search unit 14 sequentially determines the coordinates of those grids for all the grids that need to be determined as to whether or not they can be vacated. In addition to the transfer to the movement possibility investigating unit 15, the judgment result is received from the existing wiring movement possibility investigating unit 15.

Based on these results, the wiring route searching unit 14 further finds a route that minimizes the cost function 3 by using the maze method, and obtains information on the found route, that is, from which grid to which grid. Data about which grid to reach through the signal line 10
4 to the output processing unit 5. Output processing unit 5
Receives the route information and transfers the information to the wiring route search result storage unit 6 via the signal line 105. The wiring route search result storage unit 6 stores information on the transferred route. It should be noted that a wiring device is used as shown in FIG. 15 to finally determine all the wirings based on the route searched by the wiring route inspection device in the manner described above.

FIG. 2 is a flowchart showing a processing procedure executed by the already-wired-movability investigating unit 15. That is, this flowchart shows the processing procedure from receiving the coordinates of the grid from the wiring route search unit 14 to determining whether or not the grid can be opened. In FIG. 2, “g” indicates a grid indicated by the coordinates transferred from the wiring route search unit 14, that is, a grid for which it is necessary to check whether or not the space can be opened.

As shown in FIG. 2, when the process is started, first, at step 21, it is checked whether or not a terminal exists in the grid g. If it is determined that the grid g exists, it is determined that the grid g cannot be vacated,
The process ends. Conversely, if it is determined that there is not, the process proceeds to step 22.

In step 22, in a grid adjacent to the grid g (a grid separated by one grid in the east-west north-south vertical direction), the direction in which the wiring extends from the grid g through the adjacent boundary (east-west north-south vertical top and bottom) ), The positions of the grids are variables h (0), h (1),.
(N-1) is set. Here, the number of these grids is set as the natural number N.

Next, the process proceeds to a step S23. In step 23, the control variable I is initialized to "1". Next, the process proceeds to step 24, where the control variable I and the number N are compared. As a result of the comparison, if the control variable I is not smaller than the number N, it is determined that the grid g can be opened, and the process ends. Conversely, if the control variable I is N
If not, the process proceeds to step 25.

In step 25, it is determined whether or not there is a path connecting the grid at the position h (0) and the grid at the position h (I) without passing through the grid g and without causing a short circuit. Can be checked using Here, it is checked using the maze method whether or not there is a path that does not cause a short circuit without moving the existing wiring. In the next step 26, it is determined whether the result checked in step 25 is "existing" or "not present". If the judgment result is “not present”, the grid g
Is determined not to be available, and the process ends.
If the determination result is “exist”, the process proceeds to step 27.

In step 27, the control variable I is set to "
After "1" is added, the process returns to step 24. Thereafter, until it is determined whether or not the grid g can be opened, the control variable I is incremented by one while steps 24 to 27 are performed. Is repeated.

With reference to the wiring problem shown in FIG. 10 as an example, the processing in the already-moved wiring possibility investigating unit 15 will be further described. FIG. 3 is a schematic diagram illustrating a process for this wiring problem. As shown in FIG. 3, two of the net B and the net C
It is assumed that an existing wiring is drawn between the terminals, and a process in a process of finding a path connecting the two terminals of the net A will be described.

When the coordinates of the grid g in FIG. 3 are received from the wiring route searching unit 14 in the already-wired wiring possibility investigating unit 15, the number N = 2 is set.
Is the position of the grid indicated by reference symbols h0 and h1.
(0) and (1) are set respectively. Then, a path indicated by a broken line connecting the grid at the position h (0) and the grid at the position h (1) is found by the maze method, and it is determined that the grid g can be opened.

Similarly, when the coordinates of the grids h1, f are received from the wiring route search unit 14, it is determined that these grids h1, f can be opened. Also,
When the coordinates of a grid other than the grids g, h1, and f where the existing wiring exists, such as the grid h0 and the grid where the existing wiring of the net B exists, it is determined that the grid cannot be opened.

As described above, if the route connecting the two terminals of the net A shown in FIG. 3 is searched using the wiring route inspection apparatus of this embodiment, the optimum route p shown in FIG. 12 can be found. it can. At this time, the number of short circuits that can be removed is three, and the number of short circuits that cannot be removed is zero. In this way, the best route is found with a high possibility, when searching for a route, if there is an existing wiring on the grid where the route should be drawn, it is considered whether or not the grid can be opened. There is nothing other than being done.

Further, in the wiring route inspection apparatus of this embodiment, as characterized by the determination in step 25, the determination as to whether or not the grid g can be opened is made by checking the existing wiring existing on the grid g by " The present invention is not limited to the determination as to whether or not “shift” can be performed. Even when the existing wiring existing on the grid g cannot be “shifted”, the existing wiring may be moved in another way.
Also in this case, it is actually possible to leave the grid g. Therefore, the apparatus of this embodiment has an advantage that a judgment close to reality is made in this respect, and an optimum route is found with a high possibility.

<Second Embodiment> Next, a wiring route inspection apparatus according to a second embodiment will be described. FIG. 4 is a block diagram showing the configuration of the wiring route inspection device of this embodiment. FIG.
, 23 is an input processing unit, 24 is a wiring route search unit,
Reference numerals 25 to 28 denote the already-movable-wire-movability investigation unit, and 123
１２８128 are signal lines.

The already-wiring-pattern storage unit 1 stores information on already-wiring, and the terminal information storage unit 2 stores information on terminals to be connected. The input processing unit 23 transmits the information of the already-stored wiring stored in the already-wiring-pattern storage unit 1 to the signal line 10.
1 and the terminal information stored in the terminal information storage unit 2 is received via the signal line 102. The input processing unit 23 further transfers the information of the terminal to be connected to the information of the already-connected wiring to the wiring path searching unit 24 via the signal line 123, and transfers the already-connected information to the already-connected wiring via the signal line 124. Transfer to the possibility investigating units 25-28.

The wiring route searching section 24 receives the information of the already-wired wiring and the information of the terminal to be connected, and finds a route connecting the terminals by using a maze method. At this time, a path that minimizes the following cost function is found.

Cost function 4 = (path length) + (constant 1) ×
(Number of short circuits that can be removed) + (constant 2) × (number of short circuits that cannot be removed): Here, the path length is a path in which the interval between grids adjacent in any of the vertical directions of east, west, north and south is “1”. , And the constant 1 is a preset numerical value, and is a positive number considerably smaller than “1”. Further, the constant 2 is a positive number set to a value much larger than “1”, and the number of short-circuits that can be removed is defined as an existing wiring having a net name different from the net name of a terminal to be connected and a route. Is the number of grids that are determined to be free by at least one of the already-routed wiring possibility investigating units 25 to 28, and the number of unremovable short circuits is
In a grid shared by a route and a route having a net name different from the net name of a terminal to be connected, the number of grids determined by all of the route-movability investigating units 25 to 28 that they cannot be freed is there.

In order to find a route that minimizes the cost function 4 described above, it is necessary to determine whether or not each grid on which an existing wiring exists can be opened. The already-wired-movability investigation units 25 to 28
It is provided to make this determination. The wiring route searching unit 14 sends the coordinates of the grid requiring this determination to the existing wiring movement possibility investigating units 25 to 28 by the signal lines 125 to 12.
8 sequentially.

The already-wired-movability checking unit 25 receives the already-wired information transferred from the input processing unit 23. Upon receiving the coordinates of the grid where the existing wiring exists from the wiring route searching unit 24, the existing wiring movement possibility investigating unit 25 determines whether or not the grid can be opened by shifting the existing wiring to the east. Find out. If it is determined that the space can be opened, the information that the space can be opened is transferred to the wiring route search unit 24 via the signal line 125, and conversely,
If it is determined that the space cannot be opened, information that the space cannot be opened is transferred.

The already-wired wiring possibility investigating units 26, 27, 28
Operate almost the same as the already-moved wiring possibility investigating unit 25. However, the already-moved wiring possibility investigating unit 26 shifts the existing wiring to the west, the already-moved wiring possibility investigating unit 27 shifts the existing wiring to the south, and the already-moved wiring possibility investigating unit 28 The difference is that shifting the wiring north will open the grid.

The wiring route searching unit 24 receives the information transferred from the already-wired wiring possibility investigating units 25 to 28, that is, the information on whether or not the wiring can be freed. That is, in order to find a route that minimizes the cost function 4, the wiring route searching unit 24 sequentially assigns the coordinates of the grids to all the grids that need to be determined as to whether or not they can be opened. Movability investigation unit 25-
28, and receives the determined result from the already-routed wiring possibility investigating units 25 to 28.

Further, based on these results, the wiring route searching unit 24 finds a route that minimizes the cost function 4 by using the maze method, and obtains information on the found route, that is, from which grid to which grid. Data about which grid to reach through the signal line 10
4 to the output processing unit 5. Output processing unit 5
Receives the route information and transfers the information to the wiring route search result storage unit 6 via the signal line 105. The wiring route search result storage unit 6 stores information on the transferred route. In order to finally determine all the wirings based on the route searched by the wiring route inspection device in the above manner, similarly to the wiring route inspection device of the first embodiment, as shown in FIG. Wiring device is used.

FIG. 5 and FIG. 6 are flowcharts showing a processing procedure executed by the already-moved-wire-movability investigating unit 25 in FIG. That is, this flowchart shows a processing procedure from receiving the coordinates of the grid from the wiring route search unit 24 to determining whether or not the grid can be opened. 5 and 6, “g” indicates a grid indicated by the coordinates transferred from the wiring route search unit 24, that is, a grid for which it is necessary to check whether or not it can be vacated.

When the process is started, first, at step 31, it is checked whether or not a terminal exists in the grid g. If it is determined that the grid g exists, it is determined that the grid g cannot be opened, and the process ends. vice versa,
If it is determined that the file does not exist, the process proceeds to step 32.

In step 32, it is checked whether or not the wiring has emerged from the grid g in the west direction through the adjacent boundary. When it is determined that the wiring is out, it is determined that the grid g cannot be opened, and the process ends. Conversely, if it is determined that there is not, the process proceeds to step 33.

In step 33, among the grids adjacent to the grid g in the direction perpendicular to the east (the grids separated by one grid in the north-south vertical direction), the wiring extends from the grid g through the adjacent boundary. The position of the grid is the variable h
(0), h (1),..., H (N−1).
Here, the number of these grids is set as the natural number N. In step 34, the position of the grid g is set to a variable h (N).

Next, the routine goes to step 35. In step 35, the control variable I is initialized to "0". Next, the routine proceeds to step 36, where the control variable I and the number N are compared. As a result of the comparison, if the control variable I is not equal to or less than the number N, it is determined that the grid g can be opened, and the process ends. Conversely, if the control variable I is equal to or less than the number N, the process proceeds to step S37.

In step 37, the position of the grid east of the grid at position h (I) is set as a variable f. In step 38, the grid at the position f is added to the grid g.
It is determined whether there is a terminal or an obstacle having a net name different from the above wiring. If there is, it is determined that the grid g cannot be opened, and the process ends. Conversely, if not, the process proceeds to step 39.

In step 39, it is determined whether or not there is an existing wiring having a net name different from the wiring on the grid g in the grid at the position f. If there is, the process proceeds to step 40, and if not, the process proceeds to step 42.
Move to.

In step 40, it is checked whether or not the grid at the position f can be opened by shifting the existing wiring to the east. In the following step 41, the result checked in step 40 is determined. If it is determined that the grid at the position f cannot be vacated, it is determined that the grid g cannot be vacated, and the process ends. vice versa,
If it is determined that the grid at the position f can be opened, the process proceeds to step 42.

At step 42, "1" is added to the control variable I. Thereafter, the process returns to step S36. Thereafter, the processes of steps 36 to 42 are repeated while adding the control variable I one by one until it is determined whether or not the grid g can be opened.

From the already-wired-movability investigating unit 25, as described above, by shifting the already-wired line on the grid g to the east, it is possible to determine whether or not the grid g can be opened. The remaining wiring movement possibility investigation unit 26
In the steps 28 to 28, the respective processes performed on the basis of the east in the already-routed wiring possibility investigating unit 25 are performed on the basis of the west, south, and north, respectively. For example, the existing wiring movement possibility investigation unit 2
In step 33 in the process of No. 7, a grid adjacent to the grid g in the direction perpendicular to the south (1
(A grid apart from the grid), the position of the grid from which the wiring extends from the grid g through its adjacent boundary is represented by variables h (0), h (1),..., H (N-1). Is set. As a result, the already-routed wiring possibility investigating units 26 to 28 determine whether or not the grid g can be opened by shifting the already-routed wire on the grid g to the west, south, or north, respectively. can get.

Taking the wiring problem shown in the schematic diagram of FIG. 7 as an example,
The processing in the already-wired-movability investigating unit 25 will be further described. As shown in FIG. 7, it is assumed that a wiring is already provided between each of the two terminals of the nets B, C, and D, and a process in a process of finding a path connecting the two terminals of the net A will be described.

It is assumed that the already-wired-movability investigating unit 25 has received the coordinates of the grid g in FIG. Then, as shown in the schematic diagram of FIG.
Since the grid g can be opened by shifting the existing wiring on the grid g to the east, the already-movable-movability investigating unit 25 determines that the grid g can be opened. Similarly, when the coordinates of the grids g1 to g7 shown in FIG. 7 are received from the wiring route searching unit 24, the already-movable wiring possibility investigating unit 25 sets the grids g1 to g7.
Is determined to be empty. In addition, when having received the coordinates of the grid on which the existing wiring exists, the already-wired-movability investigating unit 25 determines that the grid g cannot be opened.

As described above, if the route connecting the two terminals of the net A shown in FIG. 7 is searched using the wiring route inspection apparatus of this embodiment, the optimum route p shown in FIG. 12 can be found. it can.

In the apparatus of this embodiment, when moving the existing wiring on the grid g to be determined, taking into account the possibility of movement of another existing wiring which is an obstacle,
A determination is made whether the grid g can be vacated. That is, even if there is another existing wiring that hinders the movement of the existing wiring on the grid g, it can be determined that the grid g can be opened if the latter existing wiring can be moved. Therefore, there is an advantage that the existence of another existing wiring that is an obstacle does not necessarily restrict the determination result.

Third Embodiment Next, a description will be given of a wiring route inspection apparatus according to a third embodiment. FIG. 9 is a block diagram showing the configuration of the wiring route inspection device of this embodiment. In the wiring route investigation device of this embodiment, the already-moved wiring investigation unit 15 of the first embodiment is connected to the interconnection route searching unit 24 along with the already-existing wiring migration investigation units 25 to 28,
The difference from the apparatus of the second embodiment is that the information on the already-routed wiring from the input processing unit 23 is also transferred to the already-routed wiring possibility investigating unit 15 via the signal line 124.

Further, the wiring route search section 24 refers to the judgments made by the already-moved wiring possibility investigating sections 15, 25 to 28. In other words, in the grid shared by the route and the route that has a net name different from the net name of the terminal to be connected,
The number of grids determined to be able to open the grid by at least one of the already-wired-movability investigating units 15, 25 to 28 is treated as the number of short-circuits that can be removed. The number of grids determined not to be able to be opened by the already-wired wiring possibility investigating units 15, 25 to 28 is treated as the number of unremovable short circuits.

Since the device of this embodiment is configured and operates as described above, it is determined that at least one of the device of the first embodiment and the device of the second embodiment can open the grid. In such a case, it is determined that the grid can always be opened. In the apparatus of the first embodiment, it is determined that the grid can be vacated, whereas in the apparatus of the second embodiment, it is rarely determined that the grid cannot be vacated. The reverse is also possible, albeit rare. However, at least as long as it is determined that the device can be vacated, the device can actually be vacated. Therefore, a judgment corresponding to the logical sum of the two can be obtained. In the device, a judgment closer to reality can be obtained. For this reason, the device of this embodiment has the advantage that the optimal path is found with a higher possibility.

[0083]

According to the wiring route inspection apparatus of the present invention, the judgment by the already-moved wiring possibility investigating means, that is, the judgment as to whether or not the small area where the existing wiring exists can be opened is considered. , Because the route of the wiring is searched,
The best route is found with high potential.

In the wiring route inspection apparatus according to the second aspect,
It is determined whether or not the small area where the existing wiring exists can be separated by determining whether another wiring in which the wiring comes from the small area to be determined is adjacent to the small area to be determined and passes through the adjacent boundary. The determination is made according to whether or not there is a route of a wiring that does not pass between small areas without passing through the small area to be determined. For this reason, since the half-cutting is easily performed, the means for examining the possibility of moving the existing wiring can be easily configured. In addition, since the determination as to whether or not the small area can be opened is not limited to the determination as to whether or not the existing wiring existing on the small area can be shifted, a more realistic determination is made. As a result, the optimal route is found with high probability.

In the wiring route inspection device according to the third aspect,
Determining whether it is possible to open the small area where the existing wiring exists can be done by opening the small area even if there is an existing wiring that is an obstacle to moving the existing wiring out of the small area. It is not directly linked to the determination that the wiring cannot be performed, and it is considered whether or not the existing wiring that is an obstacle can be moved. For this reason, since the judgment reflecting the reality is performed, the optimum route is found with a higher possibility.

In the wiring route inspection device according to the fourth aspect,
Since it is determined whether or not the small area where the existing wiring exists can be opened by shifting the existing wiring, the determination is easily performed. For this reason, the means for investigating the possibility of existing wiring movement can be easily configured. In addition, by taking into account the possibility of movement of another existing wiring that becomes an obstacle in displacing the existing wiring, the judgment reflecting the reality is performed, so that the optimum route is found with a high possibility.

In the wiring route inspection apparatus according to the fifth aspect,
In the first mobility possibility investigating means, it is determined whether or not it is possible to open the small area where the existing wiring exists, and the judgment is made through the adjacent boundary adjacent to the small area to be judged. The determination is easily made because the route of the wiring is determined depending on whether or not there is a route of the wiring without passing through the small area to be determined between another small area where the wiring is formed from the small area. The determination as to whether or not the small area can be opened is not limited to the determination as to whether or not the existing wiring existing on the small area can be shifted. In addition, the second movement possibility investigating means determines whether or not the small area in which the existing wiring can be opened by shifting the existing wiring can be easily determined. In addition, a determination is made in consideration of the possibility of movement of another existing wiring, which becomes an obstacle in shifting the existing wiring.

The means for examining the possibility of moving the existing wiring is based on these two.
Since the results of the determinations by the two mobility possibility investigating means are so-called logical sums, the determinations closer to reality are made by compensating for the omission in each determination. For this reason, the optimal route is found with greater potential.
In addition, since the determination can be easily made in any of the movement possibility investigating means, there is an effect that the existing wiring movement possibility investigating means can be easily configured. The wiring line according to claim 6.
In the road survey method, it is necessary to determine the route
That is, whether the small area where the existing wiring exists can be opened
The route of the wiring is searched by considering the judgment
To find the best route with high potential
It is.

[Brief description of the drawings]

FIG. 1 is a block diagram of a wiring route inspection device according to a first embodiment.

FIG. 2 is a flowchart of a processing procedure of the wiring route inspection device of the first embodiment.

FIG. 3 is a schematic diagram illustrating an operation of the wiring route inspection device of the first embodiment.

FIG. 4 is a block diagram of a wiring route inspection device according to a second embodiment.

FIG. 5 is a flowchart of a processing procedure of the wiring route inspection device of the second embodiment.

FIG. 6 is a flowchart of a processing procedure of the wiring route inspection device of the second embodiment.

FIG. 7 is a schematic diagram illustrating the operation of the wiring route inspection device of the second embodiment.

FIG. 8 is a schematic diagram illustrating the operation of the wiring route inspection device according to the second embodiment.

FIG. 9 is a block diagram of a wiring route inspection device according to a third embodiment.

FIG. 10 is a schematic diagram illustrating an example of a wiring problem.

FIG. 11 is a schematic diagram illustrating an example of a wiring problem.

FIG. 12 is a schematic diagram showing an example of solving a wiring problem.

FIG. 13 is a schematic diagram showing an example of solving a wiring problem.

FIG. 14 is a block diagram of a conventional wiring route inspection device.

FIG. 15 is a block diagram of a wiring device.

[Explanation of symbols]

14, 24 wiring route searching unit (wiring route searching means), 1
5 Existing Wiring Movability Investigation Unit (Existing Wiring Mobility Investigation Means, First Movability Investigation Means) 25-28 Existing Wiring Movability Investigation Unit (Existing Wiring Movability Investigation Means, Second Movement) Possibility investigation means), 301 Wiring route investigation device.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-80881 (JP, A) JP-A-5-160375 (JP, A) JP-A-5-174103 (JP, A) JP-A-5-174103 101145 (JP, A) JP-A-63-86597 (JP, A) JP-A-2-133759 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G06F 17/50 H01L 21 / 82

Claims (6)

(57) [Claims] 1. A wiring path surveying device for searching a wiring path connecting a plurality of given terminals by sequentially following said small area within a wiring area conceptually divided into small areas by line segments. In the above, it is determined whether or not the small area can be opened with respect to the small area in which the existing wiring exists, that is, while maintaining the connection between the terminals and without causing a short circuit with another existing wiring, Whether the existing wiring existing in the area can be moved out of the small area,
Wiring route investigation means for determining a wiring route, and wiring route searching means for searching for a route of a wiring based on a result of the determination by the existing wiring movement possibility investigating means. apparatus. 2. A method according to claim 1, wherein said already-moved-wiring-movability investigating means determines whether or not the small area where the already-wired wiring exists can be vacated. To be performed between another small area through which the wiring passes from the small area to be determined according to whether or not there is a route of a wiring that does not pass through the small area to be determined. The wiring route inspection device according to claim 1, wherein: 3. The method according to claim 2, wherein the already-routed-movability investigating unit determines whether or not the small area in which the already-wired area exists can be vacated by moving the already-wired area outside the small area. 2. The wiring route inspection device according to claim 1, wherein the wiring route inspection device performs the calculation in consideration of the possibility of movement of another existing wiring. 4. A method according to claim 1, wherein said means for investigating the possibility of moving the existing wiring determines whether or not the small area in which the existing wiring can be opened is determined by determining whether or not the small area in which the existing wiring exists can be opened. The line segment is performed in accordance with whether or not it is possible to move in parallel to the outside of the small area while maintaining the connection with other parts, and further, the line segment is set in parallel to the outside of the small area. 2. The wiring route inspection apparatus according to claim 1, wherein the wiring is performed in consideration of the possibility of movement of another existing wiring which becomes an obstacle in moving the wiring. 5. The method according to claim 1, wherein the determination unit determines whether or not the small area in which the existing wiring exists can be determined by determining whether the small area in which the existing wiring exists can be opened. The process is performed according to whether or not there is a route of a wiring that passes through another small region through which the wiring is drawn from the small region to be determined without passing through the small region to be determined. (1) determining whether or not it is possible to open a small area where the existing wiring exists,
A predetermined line segment existing on the small area while configuring the already-wired wiring is performed depending on whether or not it can be moved in parallel to the outside of the small area while maintaining the connection with other parts. A second movement possibility investigating means for considering the movement possibility of another existing wiring which becomes an obstacle in moving the line segment out of the small area in parallel, and 2. The method according to claim 1, wherein when it is determined in any one of the first and second mobility possibility investigating means that the small area can be vacated, it is determined that the small area can be vacated. 3. Wiring route survey device. 6. An arrangement which is conceptually divided into small areas by line segments.
In the line area, the small area is
To search for the route of the connecting wire by sequentially following
In the route survey method, the
And whether or not the small area can be opened,
In addition, while maintaining the connection between the terminals, and other wiring already
Existing in the small area without causing a short circuit with
Whether the line can be moved out of the small area,
Process for investigating whether or not the existing wiring can be
Wiring based on the results of the decision
And a wiring route searching step of searching for a route.
Investigation method of wiring route.