JPH0896002A - Automatic element layout generation device and method therefor - Google Patents

Abstract

PURPOSE: To automate the production of an element layout that requires high accuracy and to improve the designing efficiency of the element. CONSTITUTION: The automatic element layout generation device/ method are provided with an element constitution deciding means 1 which decides the constitution of an element that uses the basic modules of a sidle type having the basic module value information and is laid out so as to satisfy the element parameter information received from an input means 7, an element area deciding means 2 which decides an element area when an element is constructed by the basic modules of a single type having the basic module layout information consisting of the basic module length/width information in the decided element constitution, a basic module arranging means 3 which arranges the basic modules of a single type in the decided element area, and a wiring means 4 which performs the wiring to secure the connection among these arranged basic modules.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an element layout automatic generation device and an element layout automatic generation method for automatically generating a highly accurate element layout of an element having a resistance value or a capacitance value in a semiconductor integrated circuit.

[0002]

2. Description of the Related Art In order to realize a high performance analog circuit such as an amplifier or a constant voltage source in a semiconductor integrated circuit, highly accurate elements such as resistors and capacitors are indispensable. However, in a semiconductor integrated circuit in which different elements are realized on the same substrate, it is difficult to improve the absolute accuracy of these elements. For example, in order to improve the absolute accuracy of the resistance value, it is effective to increase the width of the portion corresponding to the resistance on the layout. However, if the width is increased, the length increases proportionately. It is necessary to determine the accuracy of the resistance value in consideration of the layout area, and there is a limit to the improvement of absolute accuracy. Further, in the semiconductor integrated circuit, the relative accuracy is better than the absolute accuracy as compared with the case where the circuit is composed of a single element, and therefore the circuit configuration manufactured by using this feature has better performance. As a method of increasing the relative accuracy, the layout of paired elements (hereinafter referred to as “paired elements”) that require the relative accuracy is made as close as possible to reduce the influence of variations in conductivity and the like even in the same chip. be able to. Further, instead of using a peculiar layout according to the element value, the elements prepared as the basic module are configured according to the ratio, so that the layout is not easily affected by variations in the manufacturing process.

In the case of a resistance element, for example, the element value means a resistance value realized by the resistance element. Further, the pair element is, for example, in the two resistance elements A and B, a relative relationship between the resistance values of the resistance elements A and B rather than the resistance values of the resistance elements A and B, for example, 1: in both resistance values. An element in which it is important to have the relationship of 2. The element value of such a pair element is
The above-mentioned "1: 2" corresponds.

[0004]

The contrivance for improving the accuracy of the resistance value and the like as described above often depends on the skill of the analog circuit designer, for example, in consideration of the layout area. Also, layout automatic generation CA
In D, since the device for improving the accuracy as described above is not taken into consideration, when the element value is input, the wiring width in the layout is fixed and the wiring length is flexible. There is a problem in terms of accuracy because it may be automatically generated. Therefore, the layout of the element that requires high precision is still done manually, which is a troublesome work.
The present invention has been made to solve such a problem, and an element layout automatic generation device and an element layout capable of improving the efficiency of design by automating the layout creation of elements that require high accuracy. The purpose is to provide an automatic generation method.

[0005]

Means for Solving the Problems and Its Actions The element layout automatic generation device of the present invention includes element parameter information regarding elements for which layouts are automatically generated and basic module value information in a basic module that is an element that constitutes the elements. Input means for inputting at least the element parameter information and the basic module value information is supplied, and the type of the basic module having the basic module value information is used to determine the configuration of the element that satisfies the element parameter information. The element configuration determining means for performing, element configuration information regarding the element configuration determined by the element configuration determining means, and basic module layout information consisting of basic module length information and basic module width information in the basic module are supplied. The element configuration information and the basic module Element area determining means for determining an element area when the element is constituted by one type of basic module having the basic module layout information based on the layout information, and the element area determined by the element area determining means. A basic module arrangement means for arranging the one type of basic module in the element area based on information and the element configuration information, and a basic module arranged by the basic module arrangement means are connected based on the element configuration information. And wiring means for performing wiring.

With this configuration, the element configuration determination means uses one type of basic module having basic module value information supplied from the input means for the element whose layout is automatically generated, and supplies the element from the input means. A configuration of the above-mentioned element that satisfies the obtained element parameter information is determined. Based on the element configuration information and the basic module layout information determined, the element region determination means determines the element region when configuring the element in one type of basic module having the basic module layout information,
The basic module arrangement means arranges the basic module in the element region. The placed basic modules are
Wiring is performed by the wiring means. As described above, the input unit, the element configuration determining unit, the element region determining unit, the basic module arranging unit, and the wiring unit have the basic module value and the basic module layout information predesignated by the designer so as to satisfy the desired accuracy. Since only one type of basic module is used and the layout of the above elements is automatically generated so as to satisfy the element parameters of the elements to be laid out, it is possible to improve the efficiency of layout creation design of elements that require high accuracy. Act on.

The "element configuration information" corresponds to the "netlist" sent from the element configuration determining means 1 described in the embodiment.

Further, the element layout automatic generation method of the present invention comprises an input step of inputting at least element parameter information relating to an element for which a layout is automatically generated and basic module value information in a basic module which is an element constituting the element. An element configuration determining step of determining the configuration of the element that satisfies the element parameter information by using one type of the basic module having the element parameter information and the basic module value information and having the basic module value information, Element configuration information relating to the element configuration determined in the element configuration determining step and basic module layout information consisting of basic module length information and basic module width information in the basic module are supplied, and the element configuration information and the basic information are supplied. Module layout information and An element region determining step for determining an element region when the element is configured with one type of basic module having the basic module layout information, and the element region information and the element determined in the element region determining step. A basic module placement step of placing the one type of basic module in the element area based on the configuration information, and wiring for connecting the basic module placed in the basic module placement step based on the element configuration information And a wiring step.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an element layout automatic generation device of the present invention will be described below with reference to the drawings. The element layout automatic generation method of the present invention is executed by the element layout automatic generation device of the present invention.
Further, in the element layout automatic generation device according to the present embodiment, for example, when laying out the resistance element having the resistance value A as the element value, the combination of the basic modules having the resistance value B as the basic module value so that the resistance value becomes the above resistance value A And the layout in the basic module is applied according to the generated combination to complete the layout of the resistive element. When the element to be laid out is not a resistor, the element value and the basic module value are values corresponding to the element to be laid out.

As shown in FIG. 1, the element layout automatic generating apparatus in this embodiment has an input device 7, an element configuration determining means 1, an element region determining means 2, a basic module arranging means 3, and a wiring means 4. Basic module value determination means 5 and basic module layout information generation means 6 are basically provided, and further basic module generation source data storage means 9, pair placement rule storage means 14, and wiring rule storage means 15 are provided. The input device 7 includes the element configuration determining means 1,
It is connected to the element region determining means 2, the basic module arranging means 3, the basic module value determining means 5 and the basic module layout information generating means 6, and the element configuration determining means 1,
The element area determining unit 2, the basic module arranging unit 3, the basic module value determining unit 5, and the basic module layout information generating unit 6 are connected to each other. The basic module generation source data storage means 9 is connected to the basic module layout information generation means 6, the pair arrangement rule storage means 14 is connected to the basic module arrangement means 3, and the wiring rule storage means 15 is connected to the wiring means 4. It

From the input device 7, element parameter information relating to elements for which layouts are automatically generated, such as material of the above elements, element values as described above, element parameter information such as element values in paired elements, and basic module values. Is entered. In the case of a pair element, the element parameter includes each element parameter of the pair element and information on the correlation between the pair element.

The element configuration determining means 1 is supplied with the basic module value information and the element parameter information, and the element configuration determining means 1 satisfies the supplied element parameter information with the supplied basic module value information. In order to do so, how to configure the basic module having the above basic module value information is determined. For example, the resistance value is 7
For the resistance element A of KΩ and the resistance element B having a resistance value of 21 KΩ, if the basic module value information is 7 KΩ,
The resistance element A has one basic module having a basic module value of 7 KΩ, and the resistance element B has three basic modules in series. If the basic module prepared in the element layout automatic generation device has a basic module value of 5 kΩ, for example,
In the case of the above example, the resistance elements A and B cannot be formed simply by arranging the basic modules in series, so the element structure determining means 1 tries a ladder circuit.

Explaining in detail with reference to the drawings, for example,
When laying out the resistance element A having a resistance value of 7 KΩ, it is assumed that “7 KΩ” is input as the element parameter information and “5 KΩ” is input as the basic module value of the basic module. Since a resistance element having a resistance value of 7 KΩ is formed by a basic module having a resistance value of 5 KΩ, the element configuration determining unit 1 has one (r1) in series and two (r1) in parallel as shown in FIG. r2, r3),
Furthermore, two (r4, r5) configurations are generated in series, and a netlist is created based on the generated configurations. It should be noted that in FIG. 4, each of the “r1” to “r5” is 5K.
A basic module having a resistance value of Ω is shown, and the element configuration determining means 1 creates a netlist from the connection relations in these “r1” to “r5”.

In the case of a pair element, the element configuration determining means 1 creates the netlist for each element of the pair element. For example, with respect to the resistance element B having a resistance value of 21 KΩ which is paired with the resistance element A having a resistance value of 7 KΩ described above, the element configuration determining unit 1 uses the basic module (r6 to r1) having a basic module value of 5 KΩ.
4), as shown in FIG. 5, four in series (r6 to r
9), five (r10 to r14) configurations are generated in parallel, and the netlist thereof is created. It should be noted that each element that constitutes the pair element is configured by the same basic module.

The element region determining means 2 is supplied with the netlist from the element configuration determining means 1. In the case of a pair element, both netlists are supplied. or,
The element area determining unit 2 generates basic module layout information stored in a storage device (not shown) included in the element layout automatic generation device, basic module layout information supplied from the outside, or basic module layout information generation described later. The basic module layout information sent by the means 6 is supplied. The basic module layout information is information indicating the shape of the basic module having information on the basic module length corresponding to "C" and the basic module width corresponding to "D" shown in FIG. Therefore, the element area determining means 2 is supplied with the basic module layout information, and thus the width and length of the basic module can be known from the basic module layout information, the number of basic modules to be used can be known from the netlist, and the layout is performed accordingly. The area of the entire device can be determined,
The determined information is transmitted as element area information. That is, since the basic module length and the basic module width in the basic module layout information do not change, the element region has a form in which the basic modules are arranged in a matrix. In the case of the paired elements A and B described above, there are 14 basic modules (r1 to r14) as described above, and the matrix arrangement method must consider the minimization of the basic module layout area. There are 14 combinations of 1 × 14 to 14 × 1. In consideration of minimizing the layout area of the basic modules, the combination is 1 × 1.
There are four ways: 4, 2 × 7, 7 × 2, and 14 × 1. The designer specifies the optimum combination from the 14 combinations described above from the input device to determine the element area, and outputs the element area information, which is area data in which basic modules can be arranged. In this example, a 2 × 7 configuration is adopted as shown in FIG.

Regarding the element layout information supplied to the element area determining means 2, if the basic module layout information is not input to the element layout automatic generation device in advance, or the basic module layout information is input, the information is stored. When it is desired to change, the basic module value determining means 5 and the basic module layout information generating means 6 are used. The basic module value determining means 5 determines the basic module value information based on the element parameter information. For the pair element, in order to simplify the layout configuration, the basic module value determining means 5
Uses the greatest common divisor of each basic module value of the pair element as basic module value information.

Basic module layout information generating means 6
First, one of the material of the element to be laid out supplied as the element parameter information, the allowable error required for the element, and the basic module generation source data prepared in advance in the basic module generation source data storage unit 9 Based on the resistance width data which is a part and is defined for each material of the element and the correlation rule between the tolerance and the resistance width and the rule that can be actually realized at the time of layout, for example, a rule of 0.5 μm pitch, etc. Determine the resistance width of the module.
As the basic module generation source data, for each element,
There are correlation rules between errors and resistance widths, realizable resistance width and resistance length data, sheet resistance values (may exist for each resistance width), contact cell data, element interval value data, and the like.

Next, the basic module layout information generating means 6 includes the determined resistance width, the basic module value obtained by the basic module value determining means 5 or supplied as element parameter information, and the element parameter information. The resistance length of the basic module is obtained based on the material, the sheet resistance value of the basic module generation source data, and the feasible resistance length data.

Next, the basic module layout information generating means 6 determines, based on the contact cell data of the basic module generation source data, the element interval value data, and the resistance width and resistance length data obtained as described above. The basic module layout information is generated by a known method. That is, the contact width and the contact cell width in the contact cell data are determined according to the resistance width data, and the contact cell data is determined. Contact cells having such contact cell data are arranged above and below the generated resistance of the above resistance width × resistance length. Then, the element interval value data is added to the layout in which the contact cells are arranged to show cell boundaries, as shown in FIG. 3, a basic module width (D) and a basic module length (C).
Generate basic module layout information having and.
Further, the contact center coordinates are obtained. As a result, one piece of basic module layout information including the basic module length, the basic module width, the contact coordinates, the basic module layout information, and the allowable error value and the basic module value as one set is generated.

The element area determining means 2 supplies the element area information to the basic module arranging means 3, and the element structure determining means 1 supplies the netlist. When the information about the pair element has not been input from the input device 7, the basic module arrangement means 3 arranges the basic module based on the element area information and the net list.
On the other hand, when the information about the pair element is input from the input device 7, the pair arrangement rule is supplied from the pair arrangement rule storage unit 14 that stores the pair arrangement rule, and the pairing is performed in consideration of the pairing property of the element. Then, the arrangement of each element is determined.

The pair placement rule, which is the placement rule for each pair of elements, may be an placement algorithm or a template which is a template of placement rules. As an example of the placement algorithm, there is a method of selecting a target module to be placed at a position that is point-symmetric with respect to the center coordinates of the element region. In the processing method using the placement algorithm, the element A and the element B are
When and have a pairing property, the arrangement of the elements A and B is determined so that the average distance from the central coordinates to the element A and the average distance to the element B are close to each other, as shown in FIG.
The reason for carefully arranging the pair elements in this way is that the characteristics of the substrate are slightly different depending on the formation location of the elements even on the same substrate, and it is necessary to consider the difference in the above characteristics. This is because by arranging the pair elements depending on the difference, the characteristic error of the substrate is canceled and the accuracy of the pair element as a whole is improved. Further, since the same basic module is used for each element forming the pair element, the ratio accuracy of the pair element can be improved.

When the placement of each element is determined, the basic module placement means 3 provides the terminal positions of the elements at the designated positions on the upper, lower, left and right sides of the element region according to the terminal positions designated by the designer by the input means 7. In the case of a pair element, four terminal positions are designated, and in the above example, as shown in FIG. 7, terminals are provided on the left side of the element region for the element A and on the lower side of the element region for the element B. .

Further, the basic module placement means 3 places the instances of the elements A and B based on the designated terminal positions. As the arrangement algorithm, Min Cut or the like which is a general method in standard cells can be used.
FIG. 8 shows a case where the instance of the element A is arranged, and “r1” to “r5” shown in FIG. 8 correspond to “r1” to “r5” shown in FIG. The basic module arranging means 3 performs the above operation for each pair element. In this way, the basic modules are arranged and the arrangement information is transmitted.

The wiring means 4 is supplied with the above-mentioned arrangement information from the basic module arrangement means 3 and the wiring rule information from the wiring rule storage means 15. The wiring rule information includes horizontal and vertical wiring materials,
There are wiring intervals, wiring widths, and through-hole cell information. Based on the wiring rule information and the arrangement information, the wiring means 4 sets the center coordinates of the contact connecting the wiring and the element as a target, and performs automatic wiring between each instance based on the netlist information. The wiring is made by changing the horizontal and vertical wiring materials or by avoiding short-circuit with a non-target contact. As the automatic wiring algorithm, general global wiring or the like is used. In addition, in FIG.
In order to facilitate the recognition of the drawing, the case where only the element A is automatically wired is shown.

The operation of the element layout automatic generation device configured as described above will be described below with reference to FIG. In step 1, various element parameter information as described above is input for the element for which automatic layout generation is performed using the input device 7. Incidentally, when the pair element value is not input in the pair element, it is processed by itself thereafter. In step 2, it is judged whether or not the basic module layout information needs to be created. That is, if the basic module layout information already input to the element layout automatic generation device is used, or if it can be used, there is no need to create new basic module layout information. Transition. On the other hand, if you want to use basic module layout information that has not been input to the element layout automatic generation device, or if you want to change the allowable error value in the resistance of the element to be laid out, for example,
The input device 7 instructs the basic module layout information generation processing.

When the basic module layout information generation processing is instructed, the process proceeds to step 3, and the basic module value determining means 5 determines the basic module value based on the element parameter information. Next, in step 4, the basic module layout information generating means 6 determines the resistance width of the basic module based on the element parameter information, the basic module generation source data, etc., as described above, and thereafter, the resistance width and the basic module. The resistance length of the basic module is determined based on the value and the like, and basic module layout information, which is the layout information of the basic module alone as shown in FIG. 3, is generated based on the data such as the resistance width and the resistance length.

In step 5, the element configuration determining means 1
As described above, based on the element parameter information and the basic module value, an arrangement configuration of basic modules that satisfies the element parameter information by the basic module value is generated as shown in FIG. 4, and a unique name is assigned to each basic module. ,
Create a netlist of the generated configuration. Next, in step 6, the element region determining means 2 determines the element region by inputting the netlist and the basic module layout information. That is, the pair elements A and B described above have a 2 × 7 matrix arrangement, as shown in FIG.

In step 7, the basic module placement means 3 decides the placement of the basic module in the element area based on the netlist and the element area information decided by the element area decision means 2, and In the case of a pair element, which basic module in the element region is to be arranged in the element A or the element B is further determined based on the pair arrangement rule supplied from the pair arrangement rule storage unit 14. This arrangement basically suppresses the influence on the characteristics due to the process variation due to the area, so that the basic modules of the pair elements are evenly arranged and are symmetrical with respect to the vertical and horizontal centerlines in the element area. Allocate. When the allocation is decided, the input device 7 instructs where to place the element terminals on the upper, lower, left and right sides of the element area. When the terminal position is determined in this way, a unique name or instance name on the netlist is assigned to the basic module for each element. The min cut method or the like can also be applied to the allocation. The basic module placement means 3 assigns unique names or instance names to all the basic modules, and then outputs the generated information as placement information.

In step 8, the wiring means 4 automatically wires between the terminals of the basic module based on the arrangement information and the net list. In the automatic wiring, different wiring materials are used for the vertical wiring and the horizontal wiring, through-hole cells are placed at the bending points, and the basic modules are connected one by one according to the above netlist. After all wiring is completed, the wiring is given a specific width and converted into actual layout data. This completes the element layout data.

As described above, in the element layout automatic generation apparatus of this embodiment, the basic module already input to the element layout automatic generation apparatus or the basic module created by the element layout automatic generation apparatus is used. , Since the element layout is automatically generated using only the pre-registered basic module having the desired basic module value and basic module layout information, the relative accuracy with the element using the same basic module on the circuit can be improved. It is possible to improve the design efficiency.

Further, in the element layout automatic generation device of the present embodiment, the element layout can be automatically generated only by the previously registered basic module for the element having the pairing property, so that the same basic module is formed on the circuit. It is possible to improve the relative accuracy with the element using, and it is possible to realize a layout with a high relative accuracy that suppresses the variation due to the area deviation in the chip between the pair elements.
Also, the design efficiency can be improved.

Further, in the element layout automatic generation device of the present embodiment, since the pair elements are arranged based on the pair arrangement rule for the elements having the pairing property, the element layout according to the required accuracy can be automatically generated. It is possible to realize an element layout with a high ratio accuracy of, a small area, and improve design efficiency.

[0033]

As described above in detail, according to the present invention, only one type of basic module having basic module values and basic module layout information designated by the designer in advance so as to satisfy the desired accuracy is used. The layout of the basic module is arranged so as to satisfy the element parameters of the element to be laid out, and the layout of the element is automatically generated according to this layout, so that it is possible to improve the efficiency of the layout creation design of the element that requires high accuracy. it can.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration in an embodiment of an element layout automatic generation device of the present invention.

FIG. 2 is a flowchart showing an operation of the element layout automatic generation device shown in FIG.

3 is a plan view showing the shape of a basic module used in the element layout automatic generation device shown in FIG. 1. FIG.

FIG. 4 is a view showing a state in which basic modules are arranged so as to satisfy element parameters by the element configuration determining means shown in FIG.

5 is a diagram showing a state in which basic elements are arranged so as to satisfy element parameters by the element configuration determining unit shown in FIG.

FIG. 6 is a diagram showing a state in which paired elements are arranged in an element region by the element region determining means shown in FIG.

7 is a diagram showing a state in which element terminals are added to the state shown in FIG.

8 is a diagram showing a state in which an instance name is added to the state shown in FIG.

FIG. 9 is a diagram showing a state in which a wiring route between basic modules is added to the state shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Element structure determination means, 2 ... Element area determination means, 3 ... Basic module arrangement means, 4 ... Wiring means, 5 ... Basic module value determination means, 6 ... Basic module layout information generation means, 7 ... Input means, 9 ... Basic module generation source data storage means, 10 ... Basic module layout information storage means.

Claims (6)

[Claims] 1. Input means for inputting at least element parameter information regarding an element whose layout is automatically generated and basic module value information in a basic module which is an element constituting the element, and information regarding the element parameter and the basic module. The element configuration determining means for determining the configuration of the element satisfying the element parameter information using one type of the basic module having the value information supplied and the basic module value information, and the element configuration determining means. Element configuration information regarding the element configuration and basic module layout information including basic module length information and basic module width information of the basic module are supplied, and the basic module layout is based on the element configuration information and the basic module layout information. information An element region determining means for determining an element region when the element is configured by one kind of basic module having, and the element based on the element region information and the element configuration information determined by the element region determining means. Basic module placement means for placing the one type of basic module in the area, and wiring means for performing wiring for connecting the basic module placed by the basic module placement means based on the element configuration information. An element layout automatic generation device characterized by the above. 2. When the element whose layout is automatically generated is a pair element in which the element parameter information has a correlation, the element parameter includes each element parameter in the pair element and the information on the correlation, 2. The input means inputs the element parameter information for each element forming the pair element, and the basic module arrangement means arranges the one kind of basic module based on the element parameter in the pair element. The element layout automatic generation device described. 3. A basic module generation source data storage means for storing basic module generation source data, which is information necessary for generating a basic module, and information on the element parameters supplied from the input means, and laid out. The resistance length information and the resistance width information of the basic module are determined based on the tolerance information required for the element and the basic module generation source data, and the basic module layout information is generated and generated based on the resistance length information and the resistance width information. 3. The element layout automatic generation device according to claim 1, further comprising a basic module layout information generation means for sending the basic module layout information to the element area determination means and the wiring means. 4. An input step of inputting at least element parameter information regarding an element for which a layout is automatically generated and basic module value information in a basic module that is an element constituting the element, and information regarding the element parameter and the basic module. The element configuration determining step of determining the configuration of the element satisfying the element parameter information using one type of the basic module having the value information supplied and the basic module value information, and the element configuration determining step. Element configuration information regarding the element configuration and basic module layout information including basic module length information and basic module width information of the basic module are supplied, and the basic module layout is based on the element configuration information and the basic module layout information. information An element region determination step of determining an element region when the element is configured by one type of basic module having, and the element based on the element region information and the element configuration information determined in the element region determination step A basic module arranging step of arranging the one type of basic module in the area, and a wiring step of wiring for connecting the basic modules arranged in the basic module arranging step based on the element configuration information are provided. An element layout automatic generation method characterized by the above. 5. When the element for which a layout is automatically generated is a pair element in which the element parameter information has a correlation, the element parameter includes each element parameter in the pair element and information on the correlation, The element parameter information is input for each element constituting the pair element in the input step, and the one type of basic module is arranged based on the element parameter in the pair element in the basic module arrangement step. The described element layout automatic generation method. 6. The basic module based on the element parameter information supplied from the input step, the allowable error information required for the element to be laid out, and the basic module generation source data which is information necessary for generating the basic module. Of the basic module layout information based on the resistance length information and the resistance width information, the basic module layout information is generated based on the resistance length information and the resistance width information, and the generated basic module layout information is sent to the element region determining step and the wiring step. The element layout automatic generation method according to claim 4, further comprising a module layout information generation step.