JPH06149939A - Automatic arrangement design device for printed wiring board - Google Patents

Abstract

PURPOSE:To optimally arrange parts in a short time by arranging the parts by arithmetically calculating the positions of parts to minimize a total wiring length between parts. CONSTITUTION:The specific gravity of non-arranged parts is calculated by a parts specific gravity calculating means 3, and the parts are successively put in order from the heavy specific gravity by applying means 5. Then, the order of putting in the parts is stored in a parts arrangement storage means 4. Further, the least significant parts data of non-arranged parts are registered as most significant arranged parts. Next, the parts are successively processed from down to up for the arrangement of a first solution by a cluster preparing means 6, the specific gravity of adjacent parts is compared, and a cluster combining upper and lower parts is prepared. The cluster is stored in a parts data storage means 2. When the cluster is prepared, the specific gravity is also compared between that part and the upper part, and a cluster defining that cluster as a component, is prepared as well. Then, the specific gravity is compared between the cluster and the parts which are not contained in the cluster but remained, and the overlapped arrangement in the order of weight is calculated from the downside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic layout designing device for designing a wiring route of a printed wiring board, and more particularly to a layout designing device for searching a layout position of parts.

[0002]

2. Description of the Related Art Generally, a problem of an automatic layout designing apparatus for a printed wiring board is to find a layout in which the total wiring length of wirings connecting components is minimum. In principle, a method is conceivable in which the total wiring length is calculated for every possible combination of all components and the combination having the smallest value is selected. However, the number of combinations in this case is the factorial N! It is not practical because it requires a huge amount of calculation.

On the other hand, as a practical method for arranging components in a conventional layout designing apparatus, there has been known an automatic component arranging method in which components are automatically rearranged and the total wiring length is reduced to be sequentially selected.

In the method of repeatedly selecting wirings whose total wiring length is reduced by simply exchanging components, an arrangement is selected in which the total wiring length is increased regardless of which component is finally exchanged. However, there are a plurality of arrangements having this feature. Since it exists, a reliable method for obtaining the optimum solution with the correct total wiring length is required. For this reason, we have tried to obtain the optimal solution by using the simulated annealing method that utilizes the principle of state transition due to the disturbance during the heating of the molecule to search the placement position of the component. Also, a method has been used in which a line (rat's nest) that connects component terminals is displayed on the display unit, and a graph of the density of wiring that traverses the substrate is displayed to allow the operator to specify the placement position of the component.

[0005]

The above-described conventional automatic layout designing apparatus for the simulated annealing method has a problem that it takes an infinite amount of time to obtain an optimum layout because of trial and error using random factors. It was
Further, in the method of allowing the operator to specify the arrangement position of the components, the components are moved one by one, so that there is a problem that many component movement operations are repeated and a long time is required to obtain the optimum component arrangement.

The object of the present invention is to solve these problems,
An object of the present invention is to provide an automatic layout design device for a printed wiring board, which can obtain an optimum component layout in a short time.

[0007]

According to the structure of an automatic layout designing apparatus for a printed wiring board of the present invention, a specific gravity calculation for calculating a specific gravity of a quotient obtained by dividing the number of wirings to be drawn out from the parts of the printed wiring by the area of the parts It is characterized by comprising means and an aligning means for arranging the parts in order of increasing specific gravity, and arranging the parts by calculating a wiring that minimizes a total wiring length between the parts.

In the present invention, a set (cluster) of parts to be connected by using the parts placement result calculated by the aligning means.
It is also possible to provide a cluster creating means for creating a cluster, and calculate the quotient (specific gravity) obtained by dividing the number of wires drawn from the cluster by the area of the cluster or the number of parts by the specific gravity calculating means, and moving the clusters collectively by the aligning means. Also, a cluster display means for displaying the cluster may be provided.

[0009]

In the present invention, the length of the net is the distance between the parts at both ends of the net, but it is necessary to arrange the parts so that this distance is minimized. Assuming that a part receives an attractive force from the net that connects it, the total net length corresponds to the total potential energy where these parts are placed, so the problem of minimizing the total net length is the problem of minimizing the total potential energy. Convert to.

The specific gravity W of a component is defined by a quotient obtained by dividing a value obtained by subtracting the number P2 of nets connected to an unplaced part from the number P1 of nets connected to an already arranged part by the area N of the part (W = (P1
-P2) / N), and the potential energy is minimized by arranging the parts from the bottom to the top in order from the part having the largest specific gravity W. In addition, the optimal placement of the components to be coupled is calculated so that the potential energy of the entire cluster is minimized by moving the cluster all at once.

[0011]

1 shows a block diagram of a first embodiment of the present invention. The automatic layout designing apparatus of this embodiment includes a display unit 10 including a cathode ray tube and the like, an input unit 12 such as a keyboard, a mouse and a communication line, and a data processing unit 13 including a control circuit, a random access storage circuit and a disk storage unit. The data processing unit 13 includes a computer having the same, and the data processing unit 13 is made up of software or a dedicated processing circuit. The component data input unit 1, the component data storage unit 2, the component specific gravity calculation unit 3, the component arrangement order storage unit 4, the alignment unit 5, and the cluster creation unit 6 are provided. It has and.

2 to 4 are flow charts showing the processing procedure of the first embodiment, and FIGS. 5 (a) to 5 (i) are schematic diagrams showing data of connection and area of parts. First, the component data input means 1 inputs the connection information and the component data of the area as shown in FIG. 5A and writes it in the component data storage means 2. In addition, in FIG. 5A, all the areas of the parts are 1.

[Procedure 1] First, in step S1 of FIG.
The component specific gravity calculating means 3 calculates the specific gravity W of the unplaced parts, and in step S2, the aligning means 5 aligns the parts in descending order of specific gravity. This order is stored in the component placement order storage means 4 as shown in FIG. Then, in step S3, the lowest part data of the unplaced parts is registered as the highest placed part. Initially, the specific gravity of any part is negative. Each time a component is registered as an already-placed component, the number P1 of nets connected to the already-placed component increases and the specific gravity of the unplaced component connected to the component increases. Therefore, as shown in FIG. 5C, the specific gravity W of the unplaced parts is calculated again and the parts are aligned. This process is shown in FIG.
Repeat this process as shown in (i) (step S
4) Finally, the arrangement of parts shown in FIG.

[Procedure 2] As shown in FIG.
When the solution in which the parts are arranged from the bottom to the top is obtained as shown in, the following processing is executed. In the arrangement according to the procedure 1 as shown in FIG. 5 (i), when there is a wiring connecting the lower part and the upper part, the specific gravity of the upper part may be higher than that of the lower part. I think.

In step S11 of FIG. 3, the cluster creating means 6 processes the parts below the first solution in order from top to bottom, compares the specific gravities of the adjacent parts, and determines the specific gravities of the parts above the lower part. If it is heavy, a cluster including upper and lower parts is created as shown in FIG. The cluster is regarded as a part whose area is the sum of the areas of its constituent parts, and the part data storage means 2
Remember. After the cluster is created, the specific gravities of the cluster and the parts on it are also compared to create a cluster having the cluster as a component (step S12).

[Procedure 3] After the cluster is created, the specific gravity of the cluster 3 obtained in the procedure 2 and the specific gravity of the remaining parts not included in the cluster are compared by the procedure 1 again, and the specific gravity is overlapped from the bottom to the top. The arrangement is calculated as shown in (b) (step S13). Further, the procedure 1 is applied to the parts inside the cluster, and the parts are rearranged as shown in FIG. 6C.

[Procedure 4] For the part group shown in FIG. 7A, the first one-dimensional arrangement 15 shown in FIG. 7B is obtained as in step 21 of FIG. 4 through steps 1 to 3. Figure 7
In (b), the first component to be arranged in the first one-dimensional arrangement is a component, but it can be changed to a component within the range of freedom of selection. The component to be arranged first is the component, and in step 22, the second component shown in FIG.
The dimension arrangement 16 is calculated.

In step 23, the cluster common to the first one-dimensional arrangement 15 and the second one-dimensional arrangement 16 is regarded as a component,
In step S24, the first one-dimensional arrangement 15 of FIG. 7 (b) and the second one-dimensional arrangement 16 of FIG. 7 (c) are set as the positions of the respective parts on the orthogonal coordinate axes, and the two-dimensional arrangement of the parts as shown in FIG. Calculate the position in the plane. Next, the component placed on the two-dimensional plane in step S25 is moved and placed near the component to which it is connected, as shown in FIG. 9 (a). Next, step S26.
Then, the parts inside the cluster are arranged to obtain a dense arrangement of the parts as shown in FIG. 9 (b).

FIG. 10 shows a block diagram of the second embodiment of the present invention. In this embodiment, a component replacement placement length increase calculation means 7 is added to the first embodiment. In this example,
It has a cluster creating means 6 for creating a cluster having a hierarchical structure on the basis of the following three criteria, and a component replacement wiring length increase calculating means 7 for performing the calculation necessary for this purpose. (1) The first condition is that all parts in a cluster are connected in the cluster. (2) A cluster is two partial clusters (or parts)
The specific gravity of the upper partial cluster is heavier than that of the lower partial cluster, and the exchange of upper and lower partial clusters has a binding force that reverses the order of specific gravity. The condition of. (3) The component replacement wiring length increase calculation means 7 is used to calculate the increase amount G of the total placement line due to the replacement of the upper and lower positions of the partial clusters of the cluster.
Calculate with. The third condition is that this value G concerning the exchange of partial clusters in a cluster should not become negative.

On the other hand, the component exchange wiring length increase calculation means 7 increases the total wiring length G by the component position exchange accompanied by the rotation of the component.
Is calculated as follows.

The parameters of the equation are shown in FIG. The specific gravity of the component [2] arranged below is B, the specific gravity of the component [1] arranged above is W, the area of the component [2] is N,
The area of the part [1] is n. It is assumed that the number of the wiring extending above the component [1] is i, and the end of the wiring is at the position 1i above the center of the component [1]. It is assumed that the number of the wiring connected to the lower part [2] is k, and the end of the wiring is 1 k below the center of the part [1]. Other than that, the number of the wiring extending downward is j, and the end of the wiring is assumed to be at the position 1j below the center of the component 1.

It is assumed that the number of the wiring extending below the component [2] is q, and the end of the wiring is 1q below the center of the component [2]. It is assumed that the number of the wiring connected to the upper part [2] is m and the end of the wiring is 1 m above the center of the part [2]. It is assumed that the number of the wiring extending upwards other than that is p and the end portion of the wiring is located 1p above the center of the component [2]. Also, sN and sn are
With respect to the component [2] or the component [1], a variable having a value of 1 when the component is rotated by 180 degrees and a value of 0 otherwise is selected so that the increment G in the following equation is minimized. here,
The number of coefficients m and the number of coefficients k are both parts [1] and parts [2].
Represents the number of wires connecting

[0023]

Table 1 below shows the selection criteria of each procedure of the second embodiment of FIG. 10, and FIG. 12 shows its state transition diagram.

[0025]

[Table 1]

FIG. 13 and FIG. 14 are schematic views of the component placement processing of each procedure of this embodiment.

[Procedure 1] The parts specific gravity calculating means 3 calculates the specific gravity of the parts, and the parts arranging means 5 arranges the unplaced parts data from the bottom to the top in order from the parts having the higher specific gravity W to the parts arrangement order storage means 4. Remember. The non-placed component having the maximum specific gravity is set as the component, and the uppermost placed component is set as the component.

[Procedure 2] In the case of state 1 as shown in FIG. 13 (a), if the specific gravity of the newly placed component is lighter than or equal to the already placed component, the newly placed component is placed on the already placed component, and A cluster including the whole is created, this cluster is regarded as a component, and the component under the cluster is regarded as a component. If there is no part under the cluster which is the part here, the procedure returns to step 1.

[Procedure 3] In either case of the state 1 and the state 2 which is extended later, when the specific gravity of the component is heavier than the specific gravity of the component, the component exchange wiring length increase calculation means 7 is used to exchange the positions of the components. The increase amount G of the total wiring length is calculated. At this time, parameters (sn, S
N) is set. If G is minimized when the part is rotated 180 degrees, it is assumed that the part is rotated.

[Procedure 4] As shown in FIG. 13B, when the specific gravity of the component is heavier than the specific gravity of the component and the value G becomes negative in both the states 1 and 2, the component is placed under the component. The arrangement is changed to, a cluster including both is created, this is regarded as a part, and the part below is regarded as a part, and both are compared to each other, and the state 1 is set. If there is no part under the cluster which is the part here, the procedure returns to step 1.

[Procedure 5] State 1 as shown in FIG.
In either case of state 2, when the specific gravity of the component is heavier than the specific gravity of the component, the value G does not become negative, and the component is a single component that is not a cluster, a cluster in which the component is arranged on the component is created. A cluster is regarded as a part, and a part under this cluster is regarded as a part. If there is no part under the cluster which is the part here, the procedure returns to step 1.

[Procedure 6] State 1 as shown in FIG.
In either case of state 2, if the specific gravity of the part is heavier than the specific gravity of the part, the value G does not become negative, and the part is a cluster, the cluster is decomposed into the parts in it The parts are used as the parts, and a cluster having a three-part configuration in which the parts are arranged on the parts is created, and a state 2 in which the parts are compared with each other is set.

[Procedure 7] In the case of state 2 as shown in FIG. 14B, when the specific gravity of the parts is lighter than or equal to the parts, a cluster including the parts and the parts is created, and the parts are arranged on the cluster. Then, a larger cluster is created, and it is regarded as a part, and the part under it is regarded as a part, and the two are compared and the state is set to 1. If there is no part under the cluster which is the part here, the procedure returns to step 1.

[Procedure 8] When a series of processes from Procedure 1 to Procedure 7 is executed for the component group as shown in FIG. 15 (a) stored in the component data storage means 2, the component is hierarchized as shown in FIG. 15 (b). A first one-dimensional arrangement 15 is obtained, which is surrounded by clusters of structures and arranged one-dimensionally. Next, the first component to be placed is changed within the range of the degree of freedom of its selection, and the processes from step 1 to step 5 are executed again until the end, and the second 1st step is performed as shown in FIG.
The dimension arrangement 16 is calculated.

These first and second one-dimensionally arranged parts are put together in a cluster common to both parts and regarded as parts. The component position of the first one-dimensional arrangement 15 and the component position of the second one-dimensional arrangement 16 are positions on the orthogonal coordinate axes of the component, and the position of the component on the two-dimensional plane is calculated as shown in FIG. These parts are moved and densely packed to obtain an arrangement with a minimum total wiring length as shown in FIG. If the cluster is placed with the parts,
Place the parts in the cluster and finish the arrangement of all parts.

In this embodiment, clusters having a hierarchical structure are created, and the clusters of all layers are rearranged so that the wiring length is minimized. Therefore, the layout with the minimum total wiring length can be calculated strictly. Moreover, the number of times this component placement is calculated is at most on the order of N ² where N is the total number of components, and the number of conventional computations N! Strictly required to calculate the placement with the minimum total wiring length is! It has the feature that the best part placement can be calculated with a sufficiently small number of calculations compared to.

FIG. 18 shows a block diagram of the third embodiment of the present invention. The present embodiment has a pre-cluster creating means 8 for creating a cluster in advance, and arranges the cluster and parts according to the specific gravity. FIG. 19 is a flowchart showing the processing procedure of the pre-cluster creating means 8.

[Procedure 1] Since the total number of all clusters of parts to be combined is a huge number of 2 to the Nth power of the number of parts (2 ^N ), it is difficult to create all the clusters in advance. Therefore, the pre-cluster creating unit 8 pre-creates useful clusters in a practical number only for clusters having particularly large cohesive force based on the following conditions.

(1) The first condition is that all parts in a cluster are connected in the cluster.

(2) A value obtained by adding a negative sign to the number of wires (C / N) depending on the number C of wirings and the number N of parts included in the cluster is calculated as the initial specific gravity W of the cluster (W =- C / N).

The specific attractive force g for attracting the partial cluster including the cluster to the cluster is calculated by the specific attractive force calculation means 9 shown in FIG.
As shown in 0, the number of wires connected in the cluster is c1,
The number of wirings connected to the outside of the cluster is c2, the number of parts of the partial cluster is n, and calculation is performed by g = (c1-c2) / n.

The second condition is that the specific attractive force g of this partial cluster is larger than the absolute value of the initial specific gravity W of the cluster (g> C / N). The purpose of this second condition was set to create tightly coupled clusters of each subset. The prior cluster creating means 8 creates a cluster by the following procedure.

[Procedure 1-1] Like the parts in the parts group of FIG. 21 (a), in step S31 of FIG. 19, a part pair having the maximum number of wires connecting the two parts is selected as a core of the cluster. Go to 1-2.

[Procedure 1-2] In step S32, the specific attractive force g of all parts of the cluster is calculated by the specific attractive force calculating means 9. As in the cluster (10) of FIGS. 21D to 21F, the specific attractive force g is compared with the absolute value c / N of the specific gravity in step S33,
If there is a part whose specific gravity g is the absolute value C / N or less of the specific gravity of the whole, proceed to step 1-3. If the specific gravity g of each component is larger than the absolute value C / N of the overall specific gravity in step S33 as in the cluster of FIG. 21B, the procedure proceeds to step 1-4.

[Procedure 1-3] In step S35, this component group is arranged at the lowest position, the component specific gravity calculating means 3 calculates the specific gravity of the other components, and the aligning means 5 sequentially from the bottom to the top. Align to. A part having the highest specific gravity outside the cluster is added to the cluster, and the cluster is expanded so that the cluster (10) is expanded from FIGS.
Proceed to.

[Procedure 1-4] In step S34, the parts forming the newly-created cluster are replaced with the newly-created cluster, and the procedure goes to procedure 1-1.

[Procedure 1-5] When all parts are assembled into one cluster as shown in FIG. 21 (g), the cluster creating process is terminated.

[Procedure 2] The arrangement in which the clusters and the parts are superposed from the bottom in order from the cluster having the higher specific gravity is calculated in accordance with the procedure after the procedure 3 of the first embodiment. Further, the dense arrangement of the components is calculated by the procedure 5 of the first embodiment.

In the present embodiment, a cluster having a strong coupling force between components is first created in advance, and the clusters are combined to arrange the components. Therefore, the feature is that the component arrangement that minimizes the total wiring length can be obtained quickly. is there.

FIG. 22 shows a block diagram of the fourth embodiment of the present invention. In the present embodiment, a cluster command input means 11 and a cluster display means 14 are added to the first embodiment, and the cluster display means 14 automatically arranges the parts one-dimensionally and two-dimensionally. And each cluster created by the automatic layout designing device are displayed on the display unit 10, and the cluster command input means 11 displays the clusters corresponding to the operator inputting an instruction to change the layout from the input unit 12. Can be placed.

The cluster display means 14 highlights the constituent parts of the cluster, displays the wiring connecting the cluster to external parts, and also displays the specific gravity of the cluster. The cluster command input means 11 moves the parts of the cluster collectively by inputting the instruction of the operator, and additionally deletes the constituent parts of the cluster.

[0052]

As described above, according to the present invention, since the total wiring length of the components in the one-dimensional layout of the printed wiring board is obtained with a small amount of calculation and the layout is developed on the two-dimensional plane, It is possible to reliably obtain the component arrangement with the minimum wiring length. Also, it can automatically calculate the cluster of parts with strong bonding strength,
It is possible to obtain a highly flexible layout design device that can move parts in a cluster unit.

[Brief description of drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating a processing procedure 1 of the embodiment of FIG.

FIG. 3 is a flowchart illustrating processing procedures 2 and 3 of FIG.

FIG. 4 is a flowchart illustrating a processing procedure 4 of FIG.

5A and 5B are schematic diagrams showing a creation process of the one-dimensional component arrangement example of FIG.

FIG. 6 is a schematic diagram showing an example of creating and arranging the clusters in FIG.

FIG. 7 is a schematic diagram showing an example of the one-dimensional component arrangement and the arrangement of clusters in FIG.

8 is a schematic diagram showing an example of the two-dimensional component arrangement of FIG.

FIG. 9 is a schematic diagram showing an example of crowding of the two-dimensional component arrangement of FIG.

FIG. 10 is a block diagram of a second embodiment of the present invention.

11 is a schematic diagram illustrating parameters of wiring between components in FIG.

12 is a state transition diagram of the processing procedure of FIG.

13 is a schematic diagram showing a cluster creation procedure of the processing of FIG.

FIG. 14 is a schematic diagram showing a cluster creating procedure after FIG.

15 is a schematic diagram showing the one-dimensional component arrangement and clusters in FIG.

16 is a schematic diagram showing an example of the two-dimensional component arrangement of FIG.

FIG. 17 is a schematic diagram showing an example of crowding of the two-dimensional component arrangement of FIG.

FIG. 18 is a block diagram of a third embodiment of the present invention.

FIG. 19 is a flowchart showing the processing procedure of the pre-cluster creating means shown in FIG. 18;

20 is a schematic diagram of wiring between partial clusters in the cluster of FIG.

FIG. 21 is a diagram showing an example of the cluster creation process of FIG. 18;

FIG. 22 is a block diagram of a fourth embodiment of the present invention.

[Explanation of symbols]

 1 Component Data Input Means 2 Component Data Storage Means 3 Component Specific Gravity Calculation Means 4 Component Placement Order Storage Means 5 Alignment Means 6 Cluster Creating Means 7 Component Replacement Wiring Length Increase Calculating Means 8 Pre-cluster Creating Means 9 Specific Gravity Calculating Means 10 Display 11 Operation command input means 12 Input section 13 Data processing section 14 Cluster display means 15 First one-dimensional arrangement 16 Second one-dimensional arrangement

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[Procedure amendment]

[Submission date] November 19, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

Title: Automatic layout design device for printed wiring boards

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic layout designing device for designing a wiring route of a printed wiring board, and more particularly to a layout designing device for searching a layout position of parts.

[0002]

2. Description of the Related Art Generally, a problem of an automatic layout designing apparatus for a printed wiring board is to find a layout in which the total wiring length of wirings connecting components is minimum. In principle, a method is conceivable in which the total wiring length is calculated for every possible combination of all components and the combination having the smallest value is selected. However, the number of combinations in this case is the factorial N! It is not practical because it requires a huge amount of calculation.

On the other hand, as a practical method for arranging components in a conventional layout designing apparatus, there has been known an automatic component arranging method in which components are automatically rearranged to sequentially select a layout in which the total wiring length is reduced.

In the method of repeatedly selecting wirings whose total wiring length is reduced by simply exchanging components, an arrangement is selected in which the total wiring length is increased regardless of which component is finally exchanged. However, there are a plurality of arrangements having this feature. Since it exists, a reliable method for obtaining the optimum solution with the correct total wiring length is required. For this reason, we have tried to obtain the optimal solution by using the simulated annealing method that utilizes the principle of state transition due to the disturbance during the heating of the molecule to search the placement position of the component. Also, a method has been used in which a line (rat's nest) that connects component terminals is displayed on the display unit, and a graph of the density of wiring that traverses the substrate is displayed to allow the operator to specify the placement position of the component.

[0005]

The above-described conventional automatic layout designing apparatus for the simulated annealing method has a problem that it takes an infinite amount of time to obtain an optimum layout because of trial and error using random factors. It was
Further, in the method of allowing the operator to specify the arrangement position of the components, the components are moved one by one, so that there is a problem that many component movement operations are repeated and a long time is required to obtain the optimum component arrangement.

The object of the present invention is to solve these problems,
An object of the present invention is to provide an automatic layout design device for a printed wiring board, which can obtain an optimum component layout in a short time.

[0007]

According to the structure of an automatic layout designing apparatus for a printed wiring board of the present invention, a specific gravity calculation for calculating a specific gravity of a quotient obtained by dividing the number of wirings to be drawn out from the parts of the printed wiring by the area of the parts It is characterized by comprising means and an aligning means for arranging the parts in order of decreasing specific gravity, and arranging the parts by calculating a part position that minimizes a total wiring length between the parts.

In the present invention, a set (cluster) of parts to be connected by using the parts placement result calculated by the aligning means.
It is also possible to provide a cluster creating means for creating a cluster, and calculate the quotient (specific gravity) obtained by dividing the number of wires drawn from the cluster by the area of the cluster or the number of parts by the specific gravity calculating means, and moving the clusters collectively by the aligning means. Also, a cluster display means for displaying the cluster may be provided.

[0009]

In the present invention, the length of the net is the distance between the parts at both ends of the net, but it is necessary to arrange the parts so that this distance is minimized. Assuming that a part receives an attractive force from the net that connects it, the total net length corresponds to the total potential energy where these parts are placed, so the problem of minimizing the total net length is the problem of minimizing the total potential energy. Convert to.

The specific gravity W of a component is defined by a quotient obtained by dividing a value obtained by subtracting the number P2 of nets connected to an unplaced part from the number P1 of nets connected to an already arranged part by the area N of the part (W = (P1
-P2) / N), and the potential energy is minimized by arranging the parts from the bottom to the top in order from the part having the largest specific gravity W. In addition, for the frozen parts, the optimum placement is calculated so that the potential energy of the entire cluster is minimized by moving the cluster at once.

[0011]

1 is a block diagram of a first embodiment of the present invention. The automatic layout designing apparatus of this embodiment includes a display unit 10 including a cathode ray tube and the like, an input unit 12 such as a keyboard, a mouse and a communication line, and a data processing unit 13 including a control circuit, a random access storage circuit and a disk storage unit. The data processing unit 13 includes a computer having the same, and the data processing unit 13 is made up of software or a dedicated processing circuit. The component data input unit 1, the component data storage unit 2, the component specific gravity calculation unit 3, the component arrangement order storage unit 4, the alignment unit 5, and the cluster creation unit 6 are provided. It has and.

2 to 4 are flow charts showing the processing procedure of the first embodiment, and FIGS. 5 (a) to 5 (i) are schematic diagrams showing data of connection and area of parts. First, the component data input means 1 inputs the connection information and the component data of the area as shown in FIG. 5A and writes it in the component data storage means 2. In addition, in FIG. 5A, all the areas of the parts are 1.

[Procedure 1] First, in step S1 of FIG.
The component specific gravity calculating means 3 calculates the specific gravity W of the unplaced parts, and in step S2, the aligning means 5 aligns the parts in descending order of specific gravity. Although the arrangement order is illustrated in FIG. 5B, it is stored in the component arrangement order storage means 4. Then, in step S3, the lowest part data of the unplaced parts is registered as the highest placed part. Initially, the specific gravity of any part is negative. Each time a component is registered as an already-placed component, the number P1 of nets connected to the already-placed component increases and the specific gravity of the unplaced component connected to the component increases. Therefore, as shown in FIG. 5C, the specific gravity W of the unplaced parts is calculated again and the parts are aligned. This process is shown in FIG.
This process is repeated as shown in (d) to (i) (step S4), and finally the component arrangement shown in FIG.
Proceed to.

[Procedure 2] As shown in FIG.
When the solution in which the parts are arranged from the bottom to the top is obtained as shown in, the following processing is executed. In the arrangement according to the procedure 1 as shown in FIG. 5 (i), when there is a wiring connecting the lower part and the upper part, the specific gravity of the upper part may be higher than that of the lower part. Think strong

In step S11 of FIG. 3, the cluster creating means 6 processes the parts below the first solution in order from top to bottom, compares the specific gravities of the adjacent parts, and determines the specific gravities of the parts above the lower part. If it is heavy, a cluster including upper and lower parts is created as shown in FIG. The cluster is regarded as a part whose area is the sum of the areas of its constituent parts, and the part data storage means 2
Remember. After the cluster is created, the specific gravities of the cluster and the parts on the cluster are also compared to create a cluster having the cluster as a component (step S11).

[Procedure 3] After the cluster is created (step S13), the specific gravity of the cluster 3 obtained in the procedure 2 and the specific gravity of the remaining parts not included in the cluster are compared by the procedure 1 again, and from the bottom to the top of the specific gravity. Then, the arrangement is calculated as shown in FIG. 6 (b) (step S13). Further, the procedure 1 is applied to the parts inside the cluster, and the parts are rearranged as shown in FIG. 6C.

[Procedure 4] For the part group shown in FIG. 7A, the first one-dimensional arrangement 15 shown in FIG. 7B is obtained as in step 21 of FIG. 4 through steps 1 to 3. Figure 7
Although the first component placed in the first one-dimensional arrangement in (b) was a component, the component with the highest specific motion when starting the procedure 1 is a component in addition to the component, and both are equivalent. . The component to be arranged first is used as a component, and in step 22, the second one-dimensional arrangement 16 shown in FIG. 7C is calculated again by the procedures 1 to 3.

In step 23, the cluster common to the first one-dimensional arrangement 15 and the second one-dimensional arrangement 16 is regarded as a component,
In step S24, the first one-dimensional arrangement 15 of FIG. 7 (b) and the second one-dimensional arrangement 16 of FIG. 7 (c) are set as the positions of the respective parts on the orthogonal coordinate axes, and the two-dimensional arrangement of the parts as shown in FIG. Calculate the position in the plane. Next, the component placed on the two-dimensional plane in step S25 is moved and placed near the component to which it is connected, as shown in FIG. 9 (a). Next, step S26.
Then, the parts inside the cluster are arranged and the densely arranged positions of the parts are obtained as shown in FIG. 9B.

FIG. 10 shows a block diagram of the second embodiment of the present invention. In this embodiment, a component replacement wiring length increase calculation means 7 is added to the first embodiment. In this example,
It has a cluster creating means 6 for creating a cluster having a hierarchical structure under the following three conditions, and has a component replacement wiring length increase calculating means 7 for performing calculations necessary for this purpose. (1) The first condition is that all parts in a cluster are connected in the cluster. (2) A cluster is two partial clusters (or parts)
The specific gravity of the upper partial cluster is heavier than that of the lower partial cluster, and the exchange of upper and lower partial clusters has a binding force that reverses the order of specific gravity. The condition of. (3) The component replacement wiring length increase calculation means 7 is used to calculate the increase amount G of the total wiring length due to the replacement of the upper and lower positions of the partial clusters.
Calculate with. The third condition is that this value G concerning the exchange of partial clusters in a cluster should not become negative.

On the other hand, the component exchange wiring length increase calculation means 7 increases the total wiring length G by the component position exchange accompanied by the rotation of the component.
Is calculated as follows.

The parameters of the equation are shown in FIG. The width of the printed wiring board is d. The specific gravity of the part [2] arranged below is B, the specific gravity of the part [1] arranged above is W,
Let the area of the part [2] be N and the area of the part [1] be n. It is assumed that the number of the wiring extending above the component [1] is i, and the end of the wiring is at the position 1i above the center of the component [1]. It is assumed that the number of the wiring connected to the lower part [2] is k, and the end of the wiring is 1 k below the center of the part [1]. Other than that, the number of the wiring extending downward is j, and the end of the wiring is assumed to be at the position 1j below the center of the component 1.

It is assumed that the number of the wiring extending below the component [2] is q, and the end of the wiring is 1q below the center of the component [2]. It is assumed that the number of the wiring connected to the upper part [2] is m and the end of the wiring is 1 m above the center of the part [2]. It is assumed that the number of the wiring extending upwards other than that is p and the end portion of the wiring is located 1p above the center of the component [2]. Also, sN and sn are
With respect to the component [2] or the component [1], a variable having a value of 1 when the component is rotated by 180 degrees and a value of 0 otherwise is selected so that the increment G in the following equation is minimized. here,
The number of coefficients m (= M) and the number of coefficients k (= K) both represent the number of wires connecting the component [1] and the component [2].

M = K

G = (B−W) · N · n / d + K · (N + n) / d + 2 · Σlk + 2 · Σlm + 2 · sn · [Σli + Σlj−Σlk] + 2 · sN · [Σlp + Σlq−Σlm]

Table 1 below shows the selection criteria of each procedure of the second embodiment of FIG. 10, and FIG. 12 shows its state transition diagram.

[0026]

[Table 1]

FIG. 13 and FIG. 14 are schematic diagrams of the component placement processing of each procedure of this embodiment.

[Procedure 1] The parts specific gravity calculating means 3 calculates the specific gravity of the parts, and the parts arranging means 5 arranges the non-arranged parts data from the bottom to the top in order from the part having the higher specific gravity W to the parts arrangement order storage means 4. Remember. The non-placed component having the maximum specific gravity is set as the component, and the uppermost placed component is set as the component.

[Procedure 2] In the case of state 1 as shown in FIG. 13 (a), if the newly placed component has a specific gravity lighter than or equal to the already placed component, the newly placed component is placed on the already placed component, and A cluster including the whole is created, this cluster is regarded as a component, and the component under the cluster is regarded as a component. If there is no part under the cluster which is the part here, the procedure returns to step 1.

[Procedure 3] In either case of the state 1 and the state 2 which is extended later, when the specific gravity of the component is heavier than the specific gravity of the component, the component replacement wiring length increase calculation means 7 performs the position exchange between the components. The increase amount G of the total wiring length is calculated. At this time, parameters (sn, S
N) is set. If G is minimized when the part is rotated 180 degrees, it is assumed that the part is rotated.

[Procedure 4] As shown in FIG. 13 (b), in both the state 1 and the state 2, when the specific gravity of the component is heavier than the specific gravity of the component and the value G becomes negative, the component is placed under the component. The arrangement is changed to, a cluster including both is created, this is regarded as a part, and the part below is regarded as a part, and both are compared to each other, and the state 1 is set. If there is no part under the cluster which is the part here, the procedure returns to step 1.

[Procedure 5] State 1 as shown in FIG.
In either case of state 2, when the specific gravity of the component is heavier than the specific gravity of the component, the value G does not become negative, and the component is a single component that is not a cluster, a cluster in which the component is arranged on the component is created, and A cluster is regarded as a part, and a part under this cluster is regarded as a part. If there is no part under the cluster which is the part here, the procedure returns to step 1.

[Procedure 6] State 1 as shown in FIG.
In either case of state 2, if the specific gravity of the part is heavier than the specific gravity of the part, the value G does not become negative, and the part is a cluster, the cluster is decomposed into the parts in it The parts are used as the parts, and a cluster having a three-part configuration in which the parts are arranged on the parts is created, and a state 2 in which the parts are compared with each other is set.

[Procedure 7] In the case of state 2 as shown in FIG. 14B, when the specific gravity of the parts is lighter than or equal to the parts, a cluster including the parts and the parts is created, and the parts are arranged on the cluster. A larger cluster is created, the upper part is regarded as a part, and the lower part is regarded as a part. If there is no part under the cluster which is the part here, the procedure returns to step 1.

[Procedure 8] When a series of processes from Procedure 1 to Procedure 7 is executed on the component group stored in the component data storage means 2 as shown in FIG. 15 (a), the component is hierarchized as shown in FIG. 15 (b). A first one-dimensional arrangement 15 is obtained, which is surrounded by clusters of structures and arranged one-dimensionally. Next, the first component to be placed is changed within the range of the degree of freedom of its selection, and the processes from step 1 to step 5 are executed again until the end, and the second 1st step is performed as shown in FIG.
The dimension arrangement 16 is calculated.

These first and second one-dimensionally arranged parts are put together in a cluster common to both parts and regarded as parts. The component position of the first one-dimensional arrangement 15 and the component position of the second one-dimensional arrangement 16 are positions on the orthogonal coordinate axes of the component, and the position of the component on the two-dimensional plane is calculated as shown in FIG. These parts are moved and densely packed to obtain an arrangement with a minimum total wiring length as shown in FIG. If the cluster is placed with the parts,
Place the parts in the cluster and finish the arrangement of all parts.

In this embodiment, clusters having a hierarchical structure are created, and the clusters of all layers are rearranged so that the wiring length is minimized. Therefore, the layout with the minimum total wiring length can be calculated strictly. In addition, the number of times this component placement is calculated is at most on the order of N ² where N is the total number of components, and the number of conventional computations N! It has the feature that the best part placement can be calculated with a sufficiently small number of calculations compared to.

FIG. 18 shows a block diagram of the third embodiment of the present invention. The present embodiment has a pre-cluster creating means 8 for creating a cluster in advance, and arranges the cluster and parts according to the specific gravity. FIG. 19 is a flowchart showing the processing procedure of the pre-cluster creating means 8.

[Procedure 1] Since the total number of all clusters of parts to be combined is as large as about the Nth power of 2 parts (2 ^N ), it is difficult to create all clusters in advance. Therefore, the pre-cluster creating unit 8 pre-creates useful clusters in a practical number only for clusters having particularly large cohesive force based on the following conditions. (1) The first condition is that all parts in a cluster are connected in the cluster. (2) A value obtained by adding a negative sign to the quotient (C / N) by the number C of wires that draws out the specific gravity of the cluster and the number N of the parts that include it is calculated as the initial specific gravity W of the cluster (W = -C /
N).

The specific attractive force g by which a partial cluster of a cluster is attracted to the cluster is set by the specific attractive force calculation means 9 as c1 being the number of wirings connected within the cluster and c2 being the number of wirings connected outside the cluster. And the number of parts of the partial cluster is n, and g = (c1-c2) / n is used for calculation.

The second condition is that the specific attractive force g of this partial cluster is larger than the absolute value of the initial specific gravity W of the cluster (g> C / N). The purpose of this second condition was set to create tightly coupled clusters of each subset. The prior cluster creating means 8 creates a cluster by the following procedure.

[Procedure 1-1] Like the parts in the parts group of FIG. 21 (a), the parts pair having the maximum number of wires connecting the two parts in step S31 of FIG. -2.

[Procedure 1-2] In step S32, the specific attractive force g of all the parts of the cluster is calculated by the specific attractive force calculating means 9. As in the cluster (10) of FIGS. 21D to 21F, the specific attractive force g is compared with the absolute value c / N of the specific gravity in step S33,
If there is a part whose specific gravity g is the absolute value C / N or less of the specific gravity of the whole, proceed to step 1-3. If the specific gravity g of each component is larger than the absolute value C / N of the overall specific gravity in step S33 as in the cluster of FIG. 21B, the procedure proceeds to step 1-4.

[Procedure 1-3] The component group of the cluster being formed in step S35 is placed at the lowest position, and the component specific gravity calculating means 3
Then, the specific gravities of the other parts are calculated, and the arranging means 5 arranges the parts having the larger specific gravities in order from bottom to top. The part having the highest specific gravity outside the cluster is added to the cluster, and the process proceeds to step 1-2.

[Procedure 1-4] The cluster is registered in step S34, and the procedure proceeds to the replacement procedure 1-1 in which the parts group is regarded as one part.

[Procedure 1-5] When all parts are assembled into one cluster as shown in FIG. 21 (g), the cluster creating process is terminated.

[Procedure 2] In accordance with the procedure from the procedure 3 onward in the first embodiment, the arrangement in which the cluster and the parts are superposed in order from the cluster having the higher specific gravity is calculated. Further, the dense arrangement of the components is calculated by the procedure 5 of the first embodiment.

In the present embodiment, a cluster having a strong coupling force between components is first created in advance, and the clusters are combined to arrange the components. Therefore, it is possible to quickly obtain the component arrangement that minimizes the total wiring length. is there.

FIG. 22 shows a block diagram of the fourth embodiment of the present invention. In this embodiment, the cluster command input means 11 and
And a cluster display means 14. Cluster display means 1
Reference numeral 4 displays on the display unit 10 the result of automatic placement of parts in one dimension, the result of automatic placement in two dimensions, and each cluster created by the automatic placement design apparatus.

The cluster display means 14 highlights the constituent parts of the cluster, displays the wiring connecting the cluster to external parts, and also displays the specific gravity of the cluster. The cluster command input means 11 moves the parts of the cluster collectively by inputting the instruction of the operator, and additionally deletes the constituent parts of the cluster.

[0051]

As described above, according to the present invention, since the total wiring length of the components in the one-dimensional layout of the printed wiring board is obtained with a small amount of calculation and the layout is developed on the two-dimensional plane, It is possible to reliably obtain the component arrangement with the minimum wiring length. Also, it can automatically calculate the cluster of parts with strong bonding strength,
It is possible to obtain a highly flexible layout design device that can move parts in a cluster unit.

[0052]

[Brief description of drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating a processing procedure 1 of the embodiment of FIG.

FIG. 3 is a flowchart illustrating processing procedures 2 and 3 of FIG.

FIG. 4 is a flowchart illustrating a processing procedure 4 of FIG.

5A and 5B are schematic diagrams showing a creation process of the one-dimensional component arrangement example of FIG.

FIG. 6 is a schematic diagram showing an example of creating and arranging the clusters in FIG.

FIG. 7 is a schematic diagram showing an example of the one-dimensional component arrangement and the arrangement of clusters in FIG.

8 is a schematic diagram showing an example of the two-dimensional component arrangement of FIG.

FIG. 9 is a schematic diagram showing an example of crowding of the two-dimensional component arrangement of FIG.

FIG. 10 is a block diagram of a second embodiment of the present invention.

11 is a schematic diagram illustrating parameters of wiring between components in FIG.

12 is a state transition diagram of the processing procedure of FIG.

13 is a schematic diagram showing a cluster creation procedure of the processing of FIG.

FIG. 14 is a schematic diagram showing a cluster creating procedure after FIG.

15 is a schematic diagram showing the one-dimensional component arrangement and clusters in FIG.

16 is a schematic diagram showing an example of the two-dimensional component arrangement of FIG.

FIG. 17 is a schematic diagram showing an example of crowding of the two-dimensional component arrangement of FIG.

FIG. 18 is a block diagram of a third embodiment of the present invention.

FIG. 19 is a flowchart showing the processing procedure of the pre-cluster creating means shown in FIG. 18;

20 is a schematic diagram of wiring between partial clusters in the cluster of FIG.

FIG. 21 is a diagram showing an example of the cluster creation process of FIG. 18;

FIG. 22 is a block diagram of a fourth embodiment of the present invention.

[Explanation of reference numerals] 1 parts data input means 2 parts data storage means 3 parts specific gravity calculation means 4 parts placement order storage means 5 alignment means 6 cluster creation means 7 parts replacement wiring length increase calculation means 8 pre-cluster creation means 9 specific gravity calculation Means 10 Display unit 11 Operation command input unit 12 Input unit 13 Data processing unit 14 Cluster display unit 15 First one-dimensional arrangement 16 Second one-dimensional arrangement

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 11

[Correction method] Change

[Correction content]

FIG. 11

[Procedure 3]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 12

[Correction method] Change

[Correction content]

[Fig. 12]

[Procedure amendment 4]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 13

[Correction method] Change

[Correction content]

[Fig. 13]

[Procedure Amendment 5]

[Document name to be corrected] Drawing

[Name of item to be corrected] Fig. 14

[Correction method] Change

[Correction content]

FIG. 14

Claims (3)

[Claims] 1. A specific gravity calculating means for calculating a specific gravity of a quotient obtained by dividing the number of wires for drawing out a part of a printed wiring from the part by the area of the part, and an aligning means for arranging the parts in descending order of the specific gravity. An automatic layout design apparatus for a printed wiring board, characterized in that a wiring that minimizes a total wiring length between the components is calculated and the components are arranged. 2. A cluster creating means for creating a cluster using the component placement result calculated by the aligning means, wherein the specific gravity calculated by the specific gravity calculating means is obtained by dividing the number of wires drawn from the cluster by the area of the cluster or the number of parts. 2. The automatic layout design apparatus for a printed wiring board according to claim 1, wherein the clusters are collectively moved by the aligning means based on the specific gravity. 3. The automatic layout design apparatus for a printed wiring board according to claim 2, wherein the specific gravity calculating means comprises wiring drawn from the cluster and cluster display means for displaying the cluster.