JP4119504B2 - Wiring prohibited area setting method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wiring prohibited area setting method and a recording medium, and more particularly to a method for setting a prohibited area for wiring in a case where wiring between cells is performed by automatic wiring and a recording medium recording the method.
[0002]
In recent years, wiring between cells in a semiconductor device such as an ASIC has been performed by automatic wiring by an automatic wiring device (CAD device). In this case, there is a portion in the cell where wiring cannot be performed, and it is necessary to set as a wiring prohibited area in advance for the CAD device. On the other hand, since semiconductor devices are required to be highly integrated, it is necessary to improve wiring efficiency in automatic wiring.
[0003]
[Prior art]
Conventionally, a method of setting a prohibited wiring area in a CAD apparatus is performed as follows based on wiring data of a wiring arranged on the cell C1 shown in FIG. 10, for example. On the cell C1, L-shaped first to third wirings L1 to L3 are arranged.
[0004]
First, the coordinates of the outermost points P1 to P3 with respect to the origin O are obtained from the wiring data of the first wiring L1. That is, the coordinates (X2, Y1) of the point P1, the coordinates (X2, Y2) of the point P2, and the coordinates (X4, Y2) of the point P3 are obtained.
[0005]
Next, the coordinates of the outermost points P4 to P6 with respect to the origin O are obtained from the wiring data of the second wiring L2. That is, the coordinates (X5, Y3) of the point P4, the coordinates (X6, Y3) of the point P5, and the coordinates (X5, Y5) of the point P6 are obtained.
[0006]
Next, the coordinates of the outermost points P7 to P9 with respect to the origin O are obtained from the wiring data of the third wiring L3. That is, the coordinates (X3, Y4) of the point P7, the coordinates (X1, Y6) of the point P8, and the coordinates (X3, Y6) of the point P9 are obtained.
[0007]
Paying attention to only the Y-axis coordinates from the coordinates of the first to third wirings L1 to L3 obtained in this way, a rectangular area continuous in one direction (in this case, the X-axis direction) is used as a wiring prohibited area. Is set.
[0008]
That is, an area continuous in the X-axis direction from the minimum value to the maximum value in the Y-axis coordinates of the first wiring L1, in this case “Y1” to “Y2”, is set as the wiring prohibition area E01 for the first wiring L1. The
[0009]
Similarly, an area continuous in the X-axis direction from the minimum value to the maximum value in the Y-axis coordinates of the second wiring L2, in this case “Y3” to “Y5”, is set as a wiring prohibited area for the second wiring L2. In addition, a region continuous in the X-axis direction from the minimum value to the maximum value in the Y-axis coordinates of the third wiring L3, in this case “Y4” to “Y6”, is set as a wiring prohibition region for the third wiring L3. Is done.
[0010]
At this time, as shown in FIG. 11, since the wiring prohibition areas for both wirings L2 and L3 overlap from "Y4" to "Y5", the Y axis coordinates of both wirings L2 and L3 In this case, a continuous area in the X-axis direction from “Y3” to “Y6” is set as the wiring prohibited area E02 for both wirings L2 and L3.
[0011]
Thus, the wiring prohibited areas for the first to third wirings L1 to L3 on the cell C1 are set as two wiring prohibited areas E01 and E02 and stored in the cell library. The CAD device performs automatic wiring on the cell C1 based on the wiring prohibition areas E01 and E02 stored in the cell library.
[0012]
In the method of setting the wiring prohibition area in this way, the wiring prohibition area for each wiring is a rectangular shape that is continuous in the X-axis direction and has a simple shape, and therefore the number of data in the wiring prohibition area is small. Therefore, in the CAD apparatus, the data of the prohibited wiring area can be easily and quickly acquired from the cell library, so that the automatic wiring process can be performed in a short time.
[0013]
[Problems to be solved by the invention]
However, when the cell C2 adjacent to one side in the Y-axis direction with respect to the cell C1 performs wiring with respect to the cell C3 adjacent to the other side in the same direction, the cell C1 has a wiring prohibited area E01 continuous in the X-axis direction. , E02 are set, it is limited to wiring only in the X-axis direction. Therefore, when wiring between the cells C2 and C3 is performed in the same wiring layer as that of the cell C1, redundant wiring that largely bypasses the cell C1 is obtained. Therefore, in the method of setting the wiring prohibition area in this way, there is a problem that it is difficult to perform automatic wiring in the CAD apparatus because the degree of freedom of wiring on the cell is small.
[0014]
In addition, when the semiconductor chip is composed of multilayer wiring, generally, the wiring prohibition area for each layer is determined so as to alternate in the X-axis or Y-axis direction. When the cell C1 is formed on a semiconductor chip made of multilayer wiring, the upper or lower layer of the layer in which the cell C1 is formed has a wiring prohibited area in the Y-axis direction, so that the cells C2, C3 The wiring between them is formed linearly through contact holes using the upper layer or lower layer of the cell C1. Then, although the wiring between the cells C2 and C3 can be formed linearly, there is a problem that the wiring resistance due to the contact hole increases. Therefore, it is necessary to improve the degree of freedom of wiring in the same wiring layer as the cell in which the wiring prohibited area is set.
[0015]
The present invention has been made to solve the above-described problems, and the object thereof is to easily and quickly acquire data of a wiring prohibited area on a cell in an automatic wiring apparatus, and An object of the present invention is to provide a wiring prohibited area setting method capable of improving the degree of freedom of wiring, and a recording medium storing a wiring prohibited area set by the setting method.
[0016]
[Means for Solving the Problems]
The invention according to claim 1 is a wiring prohibition area setting method for setting a wiring prohibition area for a wiring based on wiring data of the wiring laid out on the cell, wherein the outermost point of each wiring is determined from the wiring data. Coordinates are extracted, a first wiring prohibited area that is continuous in the X-axis direction in a range not less than the minimum value and not more than the maximum value of the Y-axis coordinates of each wire is set, and the minimum and maximum values of the X-axis coordinates of each wire A second wiring prohibited area continuous in the Y-axis direction in the range below the value is set, and an AND area of the first and second wiring prohibited areas continuous in the X-axis and Y-axis directions is set as a cell wiring prohibited area. I tried to do it.
[0017]
In the invention according to claim 2, after setting the wiring prohibited area of the cell, it is determined whether or not the wiring is included in the wiring prohibited area, and if it is determined that the wiring is not included, the wiring is The prohibited wiring area that was not included was deleted.
[0018]
The invention according to claim 3 is a wiring prohibited area setting method for setting a wiring prohibited area on a macro cell based on wiring prohibited area data set for each cell of a cell laid out on the macro cell, First outermost point coordinates of each wiring are extracted from the wiring data of the wiring laid out above, and the first wiring prohibition area continuous in the X-axis direction in the range not less than the minimum value and not more than the maximum value of the Y-axis coordinates of each wiring Is set, a second wiring prohibition region continuous in the Y-axis direction in a range not less than the minimum value and not more than the maximum value of the X-axis coordinates of each wire is set, and the first and second continuous regions in the X-axis and Y-axis directions are set The AND area of the wiring prohibition area of 2 is set as a cell wiring prohibition area, the outermost point coordinates of each area are extracted from the area data of the wiring prohibition area of each cell set in cell units, and each wiring prohibition area data Of Y-axis coordinates A third prohibited wiring area that is continuous in the X-axis direction in the range from the small value to the maximum value is set, and the Y-axis direction in the range from the minimum value to the maximum value of the X-axis coordinate of each wiring prohibited area data is set. A continuous fourth wiring prohibited area is set, and an AND area of the third and fourth wiring prohibited areas continuous in the X axis and Y axis directions is set as a macro cell wiring prohibited area.
[0021]
According to the second aspect of the present invention, since the wiring prohibition area without wiring is deleted, the area where wiring is possible on the cell can be further expanded, so that the degree of freedom of wiring on the cell is further improved. be able to. In addition, since there is no extra area data, it is possible to more easily and quickly extract the wiring prohibited area data by the automatic wiring apparatus.
[0022]
According to the third aspect of the present invention, the wiring prohibited areas for the macro cells are unified in a simple shape and are arranged in a straight line in the X and Y axis directions. Accordingly, since the area data can be reduced, the area data can be easily and quickly extracted by the automatic wiring apparatus. In addition, since the wiring prohibited area has a uniform shape and is arranged in a straight line in the X and Y axis directions, the routable area becomes linear, so that automatic wiring processing by the automatic wiring device can be easily performed.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows a CAD device 11 as an automatic wiring device of a semiconductor device in the present embodiment. The CAD device 11 includes a central processing unit (hereinafter referred to as CPU) 12, a memory 13, a magnetic disk device 14, a CRT 15 as a display, a keyboard 16, and a mouse 17. The CPU 12, the memory 13, the magnetic disk device 14, the CRT 15, the keyboard 16, and the mouse 17 are connected by a system bus 18.
[0026]
The memory 13 stores in advance an automatic placement program and automatic wiring program executed by the CPU 12 and various data necessary for the execution, and temporarily stores processing results of the CPU 12 based on the automatic placement program and automatic wiring program.
[0027]
The keyboard 16 is used to input data necessary for executing a program stored in the memory 13 and to input an output command such as a processing result to the magnetic disk device 14 or the CRT 15. The mouse 17 is used for an instruction to execute a program stored in the memory 13 and an instruction to output a processing result or the like to the magnetic disk device 14 or the CRT 15.
[0028]
The magnetic disk device 14 includes a library file 14a that stores circuit data, cell data, and the like. The circuit data includes data of various elements constituting the semiconductor device and data of wiring nets connecting the elements. The cell data includes basic cell data corresponding to various elements in the circuit data and block data having a predetermined function.
[0029]
The library file 14a stores wiring prohibition areas set for the wirings together with wiring data arranged on various cells. This wiring prohibition area is set by the CPU 12 as follows, for example, for the L-shaped first to third wirings L1 to L3 arranged on the cell C1 shown in FIG. The
[0030]
2 and 3 show the setting process of the wiring prohibition area of the CPU 12.
In step S11 shown in FIG. 2, the outermost point coordinates of each wiring based on the origin O are input. That is, as shown in FIG. 10, from the wiring data of the first wiring L1, the coordinates of the point P1 (X2, Y1), the coordinates of the point P2 (X2, Y2), and the coordinates of the point P3 (X4, Y2). Are obtained respectively. Further, the coordinates (X5, Y3) of the point P4, the coordinates (X6, Y3) of the point P5, and the coordinates (X5, Y5) of the point P6 are obtained from the wiring data of the second wiring L2. Further, the coordinates (X3, Y4) of the point P7, the coordinates (X1, Y6) of the point P8, and the coordinates (X3, Y6) of the point P9 are obtained from the wiring data of the third wiring L3.
[0031]
In step S12, a rectangular wiring prohibited area continuous in the X-axis direction for each wiring is obtained. That is, an area continuous in the X-axis direction from the minimum value to the maximum value in the Y-axis coordinates of the first wiring L1, in this case “Y1” to “Y2”, is obtained as a wiring prohibited area for the wiring L1. A region continuous in the X-axis direction from the minimum value to the maximum value, in this case “Y3” to “Y5”, in the Y-axis coordinates of the second wiring L2 is obtained as a wiring-prohibited region for the wiring L2. A region continuous in the X-axis direction from the minimum value to the maximum value in the Y-axis coordinates of the third wiring L3, in this case from “Y4” to “Y6”, is obtained as a wiring inhibition region for the wiring L3.
[0032]
In step S13, it is determined whether there is an overlapping area among the wiring prohibited areas for each wiring. If there is no overlapping area, the CPU 12 proceeds to step S14 to determine and set a wiring prohibited area in the X-axis direction for each wiring. On the other hand, if there is an overlapping area, the CPU 12 proceeds to step S15 to obtain an OR area of the overlapping areas and replace it with a new area. Thereafter, the CPU 12 proceeds to step S14 and sets it as a wiring prohibited area in the X-axis direction for each wiring.
[0033]
That is, since the wiring prohibited areas of the second and third wirings L2 and L3 overlap from “Y4” to “Y5”, the CPU 12 starts from the OR area of the overlapping areas in this step S15, in this case “Y3”. "Y6" replaces the wiring prohibited area of the wirings L2 and L3. Then, the CPU 12 proceeds to step S14, and as shown in FIG. 4, the areas from "Y1" to "Y2" and "Y3" to "Y6" are the wiring prohibited areas E01, E02 in the X-axis direction for the wirings L1 to L3. Respectively.
[0034]
In step S16 shown in FIG. 3, a rectangular wiring prohibition region continuous in the Y-axis direction for each wiring is obtained. That is, an area continuous in the Y-axis direction from the minimum value to the maximum value in the X-axis coordinates of the first wiring L1, in this case from “X2” to “X4”, is obtained as a wiring prohibited area for the wiring L1. A region continuous in the Y-axis direction from the minimum value to the maximum value in the X-axis coordinates of the second wiring L2, in this case from “X5” to “X6”, is obtained as a wiring prohibited region for the wiring L2. An area continuous in the Y-axis direction from the minimum value to the maximum value in the X-axis coordinates of the third wiring L3, in this case from “X1” to “X3”, is obtained as a wiring prohibited area for the wiring L3.
[0035]
In step S17, it is determined whether there is an overlapping area among the wiring prohibited areas for each wiring. If there is no overlapping area, the CPU 12 proceeds to step S18 to determine and set a wiring prohibited area in the Y-axis direction for each wiring. On the other hand, if there is an overlapping area, the CPU 12 proceeds to step S19 to obtain an OR area of the overlapping areas and replace it with a new area. Thereafter, the CPU 12 proceeds to step S18 to set as a wiring prohibited area in the Y-axis direction for each wiring.
[0036]
That is, since the wiring prohibition areas of the first and third wirings L1 and L3 overlap from "X2" to "X3", the CPU 12 starts from the OR area of the overlapping areas in this step S19, in this case from "X1". "X4" replaces the wiring prohibited area of the wirings L1 and L3. Then, the CPU 12 proceeds to step S18, and, as shown in FIG. 4, the areas from "X1" to "X4" and "X5" to "X6" are the wiring prohibited areas E10, E20 in the Y-axis direction for the wirings L1 to L3. Respectively.
[0037]
In step S20, an AND area of each wiring prohibited area in the X-axis direction and Y-axis direction for each wiring is obtained and replaced with a new rectangular wiring prohibited area. That is, an AND area is obtained using the X-direction wiring prohibited areas E10 and E20 and the Y-axis wiring prohibited areas E01 and E02, and the AND area is a rectangular wiring prohibited area E11, E12, E21, E22.
[0038]
In step S21, it is determined whether or not each wiring prohibited area obtained in step S20 includes a wiring. If the wiring is included, the CPU 12 proceeds to step S22, determines the wiring prohibited area obtained in step S20, stores it in the library file 14a, and ends the process. On the other hand, if the wiring is not included, the CPU 12 proceeds to step S23 and deletes the area that does not include the wiring among the wiring prohibited areas obtained in step S20. Thereafter, the CPU 12 proceeds to step S22, determines the wiring prohibited area, stores it in the library file 14a, and ends the process.
[0039]
That is, since the wiring prohibited area E21 does not include wiring, the CPU 12 deletes the wiring prohibited area E21 in step S23 as shown in FIG. Then, the CPU 12 proceeds to step S22 and stores the wiring prohibited areas E11, E12, E22 for the wirings L1 to L3 in the library file 14a.
[0040]
Since the wiring prohibited area set in this way has a simple shape, the number of data is small. Further, since the wiring prohibited area is not continuous in one direction, wiring is possible in both directions (X-axis and Y-axis directions), and the wiring-enabled area on the cell is enlarged. That is, in FIG. 5, since the wiring between the cells C2 and C3 arranged in the Y-axis direction so as to sandwich the cell C1 can be provided linearly, the routable area on the cell C1 is enlarged. The Rukoto.
[0041]
The CPU 12 performs cell layout by the automatic placement program and wiring between cells by the automatic wiring program based on various data stored in the library file 14a as follows.
[0042]
FIG. 6 shows automatic placement processing and automatic wiring processing executed by the CPU 12.
In step S31, cell data stored in the library file 14a is extracted. This cell data includes the wiring prohibited area data for the wiring obtained by the above method. In this case, since the wiring prohibited area is set in a simple shape, the number of data is small, and extraction of the wiring prohibited area data by the CPU 12 is performed easily and at high speed.
[0043]
In step S32, various cells extracted in step S31 are optimally laid out according to the processing operation of the automatic placement program based on the circuit data.
In step S33, wiring between the various cells laid out in step S32 is performed according to the processing operation of the automatic wiring program based on the data of the wiring net. In this case, since the wiring prohibition area is not continuous in one direction, the area where wiring is possible on the cell is enlarged, and the degree of freedom of wiring on the cell is high. Therefore, automatic wiring processing by the CAD device 11 is easy. Thus, automatic wiring of the semiconductor device is performed.
[0044]
Also, the method for setting the wiring prohibited area shown in FIGS. 2 and 3 can be applied to the macro cell shown in FIG.
As shown in FIG. 7, in a macro cell C0 in which a plurality of cells C11 to C14 are arranged, a wiring prohibited area E for wiring is set in each of the cells C11 to C14 based on the above method. And the outermost point coordinate of the wiring prohibition area | region E of each cell C11-C14 is extracted.
[0045]
As shown in FIG. 8, a wiring prohibited area EX continuous in the X-axis direction and a wiring prohibited area EY continuous in the Y-axis direction are set based on the outermost point coordinates.
Then, as shown in FIG. 9, the AND area of the wiring prohibition areas EX and EY that are continuous in the X-axis and Y-axis directions is set as the wiring prohibition area EXY of the macro cell C0.
[0046]
In this way, the wiring prohibition area EXY of the macro cell C0 is unified in a simple shape and arranged on a straight line in the X and Y axis directions, so that the number of data can be reduced. Then, when the wiring prohibition area EXY is stored in the library file 14a and the automatic wiring process of the macro cell C0 is similarly performed in the CAD device 11, the number of data is small. Easy and fast. In addition, since the wiring prohibition area EXY has a uniform shape and is arranged in a straight line in the X and Y axis directions, the wiring possible area becomes a straight line, so that automatic wiring processing by the CAD device 11 is easy.
[0047]
Next, features of the present embodiment will be described below.
(1) The wiring prohibited areas E11, E12, E21, and E22 set by the above method have a relatively simple shape that is not continuous in one direction. Accordingly, the area data stored in the library file 14a can be reduced, and the wiring prohibited area data can be easily and quickly extracted by the CPU 12. In addition, because the wiring prohibited areas E11, E12, E21, and E22 are not continuous in one direction, wiring is possible in both directions (X-axis and Y-axis directions). And enlarged. That is, the degree of freedom of wiring on the cell can be improved. As a result, automatic wiring processing by the CAD device 11 can be easily performed.
[0048]
(2) Moreover, the wiring prohibited area E21 without wiring is deleted. Therefore, since the area where wiring is possible on the cell can be further expanded, the degree of freedom of wiring on the cell can be further improved. Further, since there is no extra area data, the CPU 12 can more easily and quickly extract the wiring prohibited area data.
[0049]
(3) In addition, the wiring prohibition area EXY can be similarly set for the macro cell C0, and the area EXY can be unified in a simple shape and arranged in a straight line in the X and Y axis directions. Therefore, when the automatic wiring process of the macro cell C0 is performed by the CAD device 11, the number of area data is small, and therefore the extraction of the wiring prohibited area data by the CPU 12 can be performed easily and at high speed. In addition, since the wiring prohibition area EXY has a uniform shape and is arranged in a straight line in the X and Y axis directions, the wiring possible area becomes a straight line, so that automatic wiring processing by the CAD device 11 can be easily performed.
[0050]
In addition, you may make it implement this invention in the following aspects other than the said embodiment.
In the above embodiment, the wiring prohibited area E21 without wiring is deleted, but it is not necessary to delete it. That is, step S21 to step S23 shown in FIG. 3 may be omitted. In this way, the data for the area E21 increases, but the setting process (step) of the wiring prohibited area of the CPU 12 is shortened, which contributes to shortening the setting time.
[0051]
In the above embodiment, the wiring prohibited area is set by the CPU 12 mounted on the automatic wiring device 11 and then stored in the library file 14a in the magnetic disk device 14, but the wiring prohibited area is set by another CPU. May be stored in the library file 14a.
[0052]
In the above embodiment, the wiring prohibited area set by the above method is stored in the library file 14a of the magnetic disk device 14, but may be recorded on another recording medium.
[0053]
【The invention's effect】
As described above in detail, according to the present invention, the wiring prohibition area data on the cell in the automatic wiring apparatus can be acquired easily and at high speed, and the wiring prohibition capable of improving the degree of freedom of wiring on the cell. It is possible to provide an area setting method and a recording medium storing a wiring prohibition area set by the setting method.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a CAD apparatus according to an embodiment.
FIG. 2 is a flowchart showing a setting process of a wiring prohibited area.
FIG. 3 is a flowchart showing a setting process of a wiring prohibited area.
FIG. 4 is an explanatory diagram showing a wiring prohibited area;
FIG. 5 is an explanatory diagram showing a wiring prohibited area;
FIG. 6 is a flowchart showing automatic placement processing and automatic wiring processing.
FIG. 7 is an explanatory diagram showing a wiring prohibited area on a macro cell;
FIG. 8 is an explanatory diagram showing a wiring prohibited area on a macro cell;
FIG. 9 is an explanatory diagram showing a wiring prohibited area on a macro cell;
FIG. 10 is an explanatory diagram showing wiring arranged on a cell.
FIG. 11 is an explanatory diagram showing a wiring prohibited area;
[Explanation of symbols]
C1 cell C0 macrocells L1 to L4 wirings P1 to P9 outermost points E01 and E02 X-axis wiring prohibition areas E10 and E20 as first wiring prohibition areas Y-axis wiring prohibition areas as second wiring prohibition areas E11, E12, E21, E22 Cell wiring prohibited area EX X-axis wiring prohibited area as third wiring prohibited area EY Y-axis wiring prohibited area EXY as macro wiring prohibited area EXY Macro cell wiring prohibited area

Claims (3)

A wiring prohibited area setting method for setting a wiring prohibited area for a wiring based on wiring data of a wiring laid out on a cell,
Extract the outermost point coordinates of each wiring from the wiring data,
Set a first wiring prohibited area continuous in the X-axis direction in a range not less than the minimum value and not more than the maximum value of the Y-axis coordinates of each wiring,
Set a second wiring prohibition area continuous in the Y-axis direction in the range not less than the minimum value and not more than the maximum value of the X-axis coordinates of each wire,
A wiring prohibited area setting method, wherein an AND area of first and second wiring prohibited areas continuous in the X-axis and Y-axis directions is set as a cell wiring prohibited area.   After setting the wiring prohibited area of the cell, it is determined whether or not the wiring is included in the wiring prohibited area. If it is determined that the wiring is not included, the wiring prohibited area that does not include the wiring is deleted. The wiring prohibited area setting method according to claim 1, wherein the wiring prohibited area is set. A wiring prohibited area setting method for setting a wiring prohibited area on a macro cell based on wiring prohibited area data set for each cell of a cell laid out on a macro cell,
Extract the outermost point coordinates of each wiring from the wiring data of the wiring laid out on the cell,
Set a first wiring prohibited area continuous in the X-axis direction in a range not less than the minimum value and not more than the maximum value of the Y-axis coordinates of each wiring,
Set a second wiring prohibition area continuous in the Y-axis direction in the range not less than the minimum value and not more than the maximum value of the X-axis coordinates of each wire,
Set the AND area of the first and second wiring prohibited areas continuous in the X-axis and Y-axis directions as a cell wiring prohibited area,
Extract the outermost point coordinates of each area from the area data of the prohibited wiring area of each cell set in cell units,
Setting a third wiring prohibited area continuous in the X-axis direction in the range not less than the minimum value and not more than the maximum value of the Y-axis coordinates of each wiring prohibited area data;
A fourth wiring prohibited area continuous in the Y-axis direction in a range not less than the minimum value and not more than the maximum value of the X-axis coordinates of each wiring prohibited area data;
A wiring prohibited area setting method characterized in that the AND area of the third and fourth wiring prohibited areas continuous in the X-axis and Y-axis directions is set as a macro cell wiring prohibited area.

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