JPS63234358A - Processor for logic circuit diagram - Google Patents

Abstract

PURPOSE:To easily extract a logic element having its distinct attributes of the area, etc., and to improve the layout job efficiency, by discriminating the logic elements having their attribute values higher than the prescribed threshold value out of those logic elements forming a logic circuit and displaying those discriminated logic element with emphasis. CONSTITUTION:An attribute memory part 1 stores the attribute values of the area, etc., on a layout pattern of each logic element. When the threshold value is designated by a threshold value setting part 2 against the attribute value, a threshold vale comparing part 3 reads successively the areas on the layout patterns of each logic element out of the part 1 and extracts an element having an area larger than the threshold value. Then the display attribute of the relevant extracted logic element is changed on a node table stored in a logic circuit information memory part 4. Thus only the logic elements having areas larger than the threshold value are displayed on a CRT 5 with change of colors. then a layout job is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Industrial Application Field) The present invention relates to a logic circuit diagram processing device, and more particularly to a device that can improve the efficiency of layout design.

(Prior art) Due to the recent improvements in the performance of graphic devices and the low price of high-performance workstations, logic circuit diagram editing devices and logic circuits are used to create and modify logic circuit diagrams according to the instructions of the designer. Logic circuit diagram processing devices such as logic circuit diagram automatic generation devices that automatically generate logic circuit diagrams from connection data indicating connection relationships between elements are becoming popular.

After the design of the logic circuit diagram is completed using the logic circuit diagram processing apparatus as described above, a layout design work is performed to design an LSi mask pattern based on the logic circuit diagram.

This layout design work requires increasing chip density and minimizing chip area. For this reason, in layout design, it is effective to preferentially arrange logic elements with larger areas on the layout pattern.

However, in the layout design work described above, the reality is that logic elements having a large area are extracted from the logic circuit diagram created by the logic circuit diagram processing apparatus based on the operator's judgment. As a result, large-area logic elements that should be placed preferentially may be overlooked, and the layout design may sometimes have to be restarted from the beginning. This reduces the efficiency of each component, especially when designing the layout of a large-scale logic circuit, as shown in the figure on the right.

(Problems to be Solved by the Invention) In conventional logic circuit diagram processing devices, it is not possible to identify, for example, logic elements with a large area on a layout pattern in a logic circuit diagram. However, there is a problem in that the efficiency of layout design work is extremely low because logic elements with large areas must be extracted based on the operator's judgment.

The present invention has been made based on the above problems, and its purpose is to easily extract logic elements with significant attributes such as area in a logic circuit diagram, thereby improving the efficiency of layout design work. It is an object of the present invention to provide a logic circuit diagram processing device.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems, the present invention provides an attribute memory that stores the unique properties associated with each logic element constituting a logic circuit diagram as attribute values. means, a threshold value specifying means for specifying a threshold value of the attribute value, and an attribute value of each logic element stored in the attribute storage means and the specified l! The classification is characterized in that it compares the magnitude with lWi and divides the logic elements into logic elements above a threshold value and logic elements below the threshold value.

(Operation) In the present invention, unique properties associated with each logic element constituting a logic circuit diagram are stored as attribute values.

Then, the stored attribute value and the threshold value of this attribute value are compared, and the logic elements are divided into logic elements whose attribute values are greater than or equal to the threshold value and logic elements whose attribute values are less than or equal to the threshold value.

Among the divided logic elements, for example, logic elements having a value equal to or higher than a threshold value are highlighted on the display means to distinguish them from other logic elements.

(Embodiment) FIG. 1 is a block diagram showing the configuration of an embodiment of an apparatus according to the present invention.

In this example, Theory I! T! The device area will be taken as an example of the device characteristics, and the case where it is applied to the logic circuit diagram shown in FIG. 2 will be explained.

As shown in FIG. 1, the logic circuit diagram processing device of this embodiment has an attribute storage unit 1 in which the area of each logic element on the layout pattern is stored as an attribute value, and an attribute storage unit 1 in which the area of each logic element on the layout pattern is stored as an attribute value. A specified threshold value specifying unit 2, an attribute value comparison unit 3 that compares the area of each logic element with its threshold value, and a logic circuit that stores information such as the shape and arrangement of each logic element on a logic circuit diagram. A diagram information storage unit 4 and a logic circuit diagram having an area larger than a threshold value selected from among the displayed logic elements by inputting information from the logic circuit diagram information storage unit 4 and displaying a logic circuit diagram as shown in FIG. Logic circuit diagram display section 5 that highlights elements
The logic circuit diagram display section 5 includes a CRT display and a display control section for controlling the display of the CRT display.

The logic circuit diagram shown in FIG. 2 includes a two-person OR circuit E1 to which data DA and DB are input, and a two-person AND circuit E2 to which an enable signal EN and a zero check signal CLK are input.
and a D-type flip 70-tub circuit (D-F/F) E in which the output of the OR circuit E1 is supplied to the data input terminal and the output of the AND circuit E2 is supplied to the clock terminal CL.
3, and a two-man power AND circuit E4 to which the output Q of this D-type flip 70 tube circuit E3 and data DC are input.

Mae ril! The attribute storage unit 1 stores the area of each logic element E1 to E4 on a layout pattern as shown in FIG. For example, the area of each of the two-person OR circuit E1 and the two-person AND circuit E2 is 2500 (millimicrons)2, and the area of the D-type flip-flop circuit E3 is 60 mm.
00 (millimicrons)2.

The threshold value specifying unit 2 includes, for example, a keyboard and a buffer memory (none of which are shown), and when a threshold value for the attribute value is input by the operator from the keyboard, the threshold value is inputted to the attribute value comparison unit via the buffer memory. Transfer to 3.

The attribute value comparison unit 3 is configured of, for example, a CPU, and stores the area of each logic element on the layout pattern in the attribute storage unit 1.
, and are compared with the threshold specified by the threshold specifying section 2 to extract logic elements having an area equal to or larger than the threshold.

The logic circuit diagram information storage section 4 stores a node table 41 and a shape information table 42 shown in FIG.

The node table 41 includes the input terminals DA, DB, EN, CL, DC, each logic element E1 . E
2. E3. Regarding nodes such as E4 and output terminal DO,
Pointers to type, display attributes, position coordinates, and shape information of each node are stored.

Further, the shape information table 42 stores shape information of each node, and each area of this table 42 is connected to each pointer of the node table 41.

Note that this logic circuit diagram information storage unit 4 is provided with a net table (not shown), which indicates the starting point of wiring between each node,
Coordinate information regarding the positions of bending points, junction points, etc. is stored.

This embodiment has the above configuration, and its operation will be explained below.

As shown in the flowchart of FIG. 5, when the processing of the logic circuit diagram processing apparatus of this embodiment is started, first, the first node name and node type are called from the node table 41 of FIG. 4 (step 601). ).

Next, it is determined whether the node type of the called node name is an input terminal or an output terminal (step 602).

When the node type is neither an input terminal nor an output terminal, that is, the node type is each of the logic elements E1 to E.
4, the process advances to step 603. Also, if the node type is input terminal DA-DC or output terminal DO
In either case, the process advances to step 606.

In step 603, the area of the logical element of the first node name stored in the attribute storage unit 1 is called.

Then, the called area is compared with the area threshold specified by the threshold value specifying unit 2, and if the called area is larger than the threshold, the process proceeds to step 605; otherwise, the process proceeds to step 606. move on.

In step 605, the display attribute in the node table 41 of the logic element having an area larger than the threshold value changes from white display to red display. Thereby, the display control section in the logic circuit diagram display section 5 controls so that only the corresponding logic element in the logic circuit diagram displayed on the CRT display is displayed in red.

Then, the areas of all logic elements are compared with the threshold value, and when the extraction processing for all logic elements is completed, the processing of this embodiment is completed.

Next, to explain the above process in detail, for example, if you want to extract logic elements whose area on the layout pattern exceeds "threshold value = 5000 (millimicrons) 2" from the logic circuit diagram shown in Figure 2. In this step, the area of each logic element and the threshold value are compared in order from the two-person chaor circuit F1.

As a result, the area on the layout pattern is r6000
(millimicron) 2'' D-type flip 7O tube circuit E3 is extracted. Then, the extracted D in the logic circuit diagram shown in Figure 2, which was initially displayed in white.
Only the type flip-flop E3 is displayed in red, and is highlighted to be distinguished from other logic elements.

Therefore, in subsequent layout design work, large logic elements having an area of rI4 or more can be easily and reliably extracted without being mistaken, and work efficiency is improved. As a result, space can be allocated effectively in terms of layout design, making it possible to miniaturize LSI chips and improve the yield of LSI chips.

In this embodiment, the area on the layout pattern is used as an example of the attribute value of the logic element, but the present invention is not limited to this. For example, the number of fan-outs, the number of fan-ins, and the number of basic cells of the logic element , the number of grids, etc. are stored in advance as attribute values, and those whose attribute values are greater than a threshold are extracted and highlighted, making it easier to check areas with dense wiring. becomes possible.

Also, if you retain the power consumption value of the logic element as an attribute and extract the logic element that exceeds the threshold value of this power value, you can design the layout of the logic element taking into consideration the power consumption, amount of heat generated, etc. Work becomes easier.

Further, in this embodiment, logical elements having attribute values exceeding a threshold value are extracted, but it is of course possible to extract logical elements having an attribute value equal to or less than the threshold value.

Furthermore, it is also possible to extract a specific logic element by combining a plurality of attribute values, such as a logic element with an area of 5000 (millimicrons) 2 or more and a fan-out number of 10 or more.

In addition, in this embodiment, the logic element exceeding the threshold value is displayed in red instead of white, but it may be configured so that only the logic element exceeding the threshold value is displayed.

[Effects of the Invention] As explained in detail above, according to the present invention, the unique properties associated with each logic element constituting a logic circuit diagram are held in advance as attribute values, and the threshold value of this attribute value and each logic element are The configuration is configured such that logical elements with attribute values equal to or higher than a threshold value are distinguished from logical elements with attribute values equal to or lower than a threshold value by comparing the attribute values of .

Therefore, logic elements with significant attribute values can be distinguished from other logic elements, greatly improving the efficiency of subsequent layout design work.
to

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the device according to the present invention, FIG. 2 is a block diagram showing a logic circuit used in the embodiment, and FIG. 3 is a block diagram showing attributes stored in the attribute recording section. FIG. 4 is a configuration diagram of a value storage area, FIG. 4 is a configuration diagram of a node table in the logic circuit diagram information storage section, and FIG. 5 is a flowchart showing the processing procedure of the embodiment device shown in FIG. 1... Attribute storage section 2... Threshold value specification section 3... Attribute value comparison section 4... Logic circuit diagram information storage section 5... Logic circuit diagram display section

Claims (2)

[Claims] (1) Attribute storage means for storing unique properties associated with each logic element constituting a logic circuit diagram as attribute values; threshold specification means for specifying a threshold value for the attribute value; A logic circuit diagram processing device comprising: a classification means for comparing the magnitude of an attribute value of each logic element with a specified threshold value and classifying the logic elements into logic elements having a value greater than or equal to the threshold value and logic elements having a value less than or equal to the threshold value. (2) The logic circuit diagram processing apparatus according to claim 1, wherein the classification means includes display means for distinguishing and highlighting logic elements having a value equal to or higher than a threshold value from logic elements equal to or less than a threshold value.