JPH03241762A - Designing method for wiring of integrated circuit - Google Patents

Abstract

PURPOSE:To realize wide wirings accurately by a method wherein a block containing a wide wiring is provided to realize the wide wiring and all the individual connections of the remaining circuits are provided by an automatic wiring method. CONSTITUTION:A functional block 2 is so designed as to have a wide wiring 8 connected to a functional device 3 beforehand in it and the wide wiring 8 itself is defined as the terminal of the block 2. As for design of wirings of individual circuits, other functional devices 4 and 5 which are to be connected to the functional device 3 are connected to the terminal 8 with wirings 6 and 7 having minimum widths. As the wirings 6 and 7 can be provided by an automatic wiring method with a constant wiring width, partially-wide wirings can be realized between the devices 4 and 5 and the device 3. In the wiring between the device 4 and the wiring 8, the wide wiring 8 is used as a terminal as a whole by the automatic wiring and the wiring is provided between the device 4 and the point on the wiring 8 nearest to the device 4. With this constitution, a redundant wiring route can be eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wiring design method for an integrated circuit that requires wiring of a plurality of widths.

[Conventional technology]

In the wiring design of integrated circuits, in order to minimize the area occupied by the wiring, the convergence of the wiring is usually set to the minimum line width allowed by design rules. However, it is necessary to use wiring thicker than the minimum line width especially for signal lines that are required to reduce wiring delay, power supply wiring through which a large current flows, and the like. However, handling wiring with multiple line widths complicates wiring processing, making it extremely difficult to realize automatic wiring.

For this reason, normal automatic wiring methods only allow one type of line width for wiring in order to speed up the wiring process, so if multiple line widths need to be used for wiring, thicker line widths are required. Conventionally, the wiring for this purpose is first manually routed, and then automatic wiring recognizes the thick wiring as a wiring prohibited area and routes the remaining signal lines using the minimum line width.

[Problem to be solved by the invention]

The above-described conventional design method has the drawbacks that the design period becomes longer due to manual intervention, and wiring errors are more likely to occur. In particular, signal lines using thick wiring must be wired completely manually from terminal position to terminal position, and the wiring route must be determined for each circuit, so this drawback is noticeable.

The purpose of the present invention is to eliminate such drawbacks, to immediately realize thick wiring by arranging blocks containing wide wiring, and to perform all remaining circuit-specific connections by automatic wiring. You only need to confirm that there are no wiring errors at the block design stage, and automatic wiring recognizes all wide wiring within a block as terminals and routes the wiring from the element to be connected to the position where it can be connected at the shortest distance. An object of the present invention is to provide a wiring design method for an integrated circuit in which redundant wiring paths are not generated.

[Means to solve the problem]

In a wiring design method for a semiconductor integrated circuit that requires wiring of multiple widths, the configuration of the present invention is to connect an active element that needs to be connected with a wide wiring and a wide wiring that connects to this functional element. The present invention is characterized in that the wide wiring is realized by a type of automatic wiring method in which the wide wiring is placed together in a functional block and the entire wide wiring in the functional block is recognized as a terminal.

〔Example〕

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a layout diagram illustrating an embodiment of the present invention. In advance, thick wiring 8 is connected to the functional element 3 in the functional block 2.
The block is designed in such a way that it is connected to the block 2, and the wide wiring 8 itself is defined as the terminal of the block 2. In the wiring design of each circuit, the other functional element 4.5 to be connected to the functional element 3 is connected to this terminal 8 using a wiring 6.7 having the minimum width. The wiring 6.7 can be wired by an automatic wiring method with a type of wiring width. As a result, a partially wide wiring 8 from the element 4.5 to the element 3 is realized. In the wiring from the element 4 to the wiring 8, automatic wiring treats the entire wide wiring as a terminal and performs wiring to the point on the wiring 8 that is the shortest distance from the element 4.

This wiring method is effective when it is desired to reduce the difference in signal propagation delay between elements 4 and 3 and between elements 5 and 3. When the wiring length from the connection point of wiring 8 and wiring 6 to the connection point of wiring 8 and wiring 7 is long, the delay in signal transmission between elements 4 and 3 and the signal transmission delay between elements 5 and 3 are The difference in delay is mainly caused by the wiring delay during this period, but since this period is realized by the wide wiring 8, the resistance is low and the delay due to the wiring is small.

FIG. 2 is a layout diagram illustrating a second embodiment of the present invention. The automatic wiring method in this wiring method is a diagram illustrating another method of defining thick wires as terminals.
It is also possible to use terminals that can only handle wiring with a minimum line width. For such automatic wiring methods,
In reality, wires that occupy two wire grids are placed in a block, but in the terminal definition, the two wires with the minimum line width are defined as if they were terminals, such as wires 9 and 10. do. As a result, the same effect as in the case of FIG. 1 can be obtained even though automatic wiring only needs to handle wiring with the minimum line width as a terminal.

〔Effect of the invention〕

As explained above, the present invention instantly realizes thick wiring by arranging blocks containing thick wiring, and performs all remaining circuit-specific connections through automatic wiring. If it is confirmed that there are no wiring errors, it is possible to realize thick wiring without errors in the wiring design of each circuit. Furthermore, by treating the entire wide wiring within a block as a terminal, there is an effect that redundant wiring paths are not generated compared to a method in which the terminal position is set at one point.

[Brief explanation of drawings]

FIG. 1 is a layout diagram for explaining one embodiment of the present invention, and FIG. 2 is a layout diagram for explaining a second embodiment of the present invention. 1... Chip, 2... Functional block,
3.4゜5...Functional element, 6. 7. 9.1
0... Wiring (minimum line width), 8... Thick wiring.

Claims (1)

[Claims] In a wiring design method for semiconductor integrated circuits that requires wiring of multiple widths, active elements that need to be connected with wide wiring and wide wiring that connects to this functional element are placed together in a functional block. A wiring design method for an integrated circuit, characterized in that the wide wiring is realized by a type of automatic wiring method in which the entire wide wiring in the functional block is recognized as a terminal.