JPS5972566A - Designing device of printed base board - Google Patents

Abstract

PURPOSE:To set a connection pattern without disturbing the wrirings within bus net groups, by dividing the surface of a printed nase board into a bus region and other two regions separated into back and forth sides of wiring centering on said bus region. CONSTITUTION:A central processor 18 calculates a connection pattern on a printed base board in accordance with the connection information given from a key input device 13. This arithmetic result is displayed to a CRT picture display device 14 and then delivered to a photoplotter 15. A bus region 2 occupied by a bus IC is obtained among the bus net groups from the connection information on distribution of parts on the base board. Then the bus net wiring direction is checked within the region 2. The region 2 is positioned on a boundary line 3, and other parts are divided into the 1st and 2nd regions 4 and 5. The terminals within the net groups are sorted into the 1st region 4 (1), the bus region 2 (2) and the 2nd region 5 (3) respectively. Then the terminals within the net groups are arranged in order of (1), (2) and (3).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a CAD (Computer Aided
The present invention relates to a printed circuit board design device, and particularly to a printed circuit board design device for designing printed circuit boards, etc.

Conventionally, this type of design equipment using CAD automatically determines the placement position of components on the printed circuit board, sets the print pattern, etc., and aims to distribute the wiring density of the printed circuit board and shorten the total wiring length. , which aims to reduce the enormous amount of effort and time required for design.

When automatic wiring of printed circuit boards is performed using this design device, an important issue is the order in which terminals within one net are connected. Conventionally, the methods for arranging the connection order of terminals in one net are: (a) method by coordinate order, that is, by X coordinate or Y coordinate;
Method of connecting in ascending order of coordinates, (b) Method of finding the center of gravity of the net, that is, the terminal farthest from the center of gravity of the net is the first terminal, and the second terminal and the following terminals are the closest to the first terminal among the remaining terminals. A method of numbering things in order is known.

However, even if you consider the placement results of ICs, connectors, and other parts based on the connection information, determine the wiring order using the above method, and perform automatic wiring, it is not always possible to obtain good results. Not exclusively.

In other words, as shown in Figure 1, the wiring of the printed circuit board includes bus wiring in which a plurality of hash nets 1 are wired in parallel, connecting several ICs in parallel. This kind of bus wiring is called a bus net group. One bus in this bus net group
It is desirable to connect the terminals sequentially from left to right or from right to left, like the connection of the terminals within the dotted lines shown in FIG. 2.

However, when the terminal order determination method within the net for this type of bus net is combined with that for other types of nets, the above (a)
If method (b) is used, as shown in FIG. 3, the wiring order within the dotted lines will be disturbed and good results will not be obtained.

Especially in the case of a group of bus nets, such disturbances are disadvantageous to the non-wealthy in relation to other bus nets. The reason for this disorder is considered to be that the terminal connection order was determined without distinguishing between terminals that are linearly connected and terminals that are not linearly connected within the bus net.

The present invention has been made in view of the above-mentioned technical problems, and provides a printed circuit board design device that can set connection patterns without disturbing the wiring within the bus node group of the printed circuit board. The purpose is to・And the feature of the present invention is that the central processing unit
The surface of the printed circuit board is divided into a bus area to be wired in a bus-ne-sito manner, and a first area and a second area that are divided into front and back in the wiring direction so as to include this bus area on the boundary line, and are connected. The pattern setting is performed in the order of the first area, the bus area, and the second area.

Embodiments of the present invention will be described below based on the drawings.

FIG. 4 is a block diagram of a program of an apparatus according to an embodiment of the present invention.

The device of this embodiment includes a keypad device 13 such as a tablet 11 and a keyboard 12, a CRT image display device 14, a photoplotter 15, and a tape puncher 1G. device 18
Further, a storage device 19 is connected to this central processing unit 18, and each of these devices is controlled by the central processing unit 18.

That is, the central processing unit 18 calculates the connection pattern on the printed circuit board according to the connection information on the printed circuit board given from the key human power device 13, records the figure of the calculation result in the storage device 19, and displays the CR1 image. device 14
At the same time, control is performed such that the image is displayed on the photoplotter 15 as a photomask.

Next, an example of an operation procedure for automatically wiring on a printed circuit board using this embodiment device will be explained.

As a result of component placement on the printed circuit board, vertical or horizontal
There are ICs that are regularly arranged in a direction, and such ICs are called bus ICs here. Bus I in this bus net group
The area occupied by C is called a bus area, and in this bus area, each bus, node, and node must be lined up linearly and in parallel.

The first step is to find the area that will become the bus area from connection information such as component placement on the printed circuit board. This bus area is, for example, area 2 surrounded by a dotted line in FIG.

Next, determine the direction in which the bus net is routed within this bus area, and if this direction is the X-axis direction, this bus area will be located on boundary line 3, as shown in Figure 5. Then, the remaining part of the printed circuit board is divided into two left and right parts, and divided into a first area 4 and a second area 5. Similarly, this direction is Y
In the axial direction, as shown in FIG. 6, the remaining portion of the printed circuit board is divided into upper and lower halves. Note that the + mark in FIGS. 5 and 6 is a mark indicating the center of the bus area 2.

Next, the terminals in Neso 1~ are classified into three types: ■ those within the first area 4, ■ those within the lotus area 2, ■ those within the second area 5, and the terminals within the net. Broadly speaking, arrange the terminals in this order: ■, ■, ■.

Then, the terminal connection order within each of the bus area 2, first area 4, and second area 5 is determined. This determination is made by determining the terminal connection order within each area in ascending order of the X coordinate in the case of FIG. 5, and in ascending order of the Y coordinate in the case of FIG. At this time, when the X coordinates have the same value in FIG. 5, the ascending order of the Y coordinate is determined, or when the Y coordinate values have the same value in FIG. 6, the ascending order of the X coordinate is determined.

If you decide the terminal connection order in the net using the following steps,
The terminals in the bus area to be routed in a straight line are ordered without interference with the terminal positions in the first and second areas 4.5, and the bus net group is arranged in such a way that straight bus nets are arranged in parallel. It will be wired accordingly.

As described above, according to the present invention, the patterns within the bus net group are not disturbed, and an efficient connection pattern can be created.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating a group of bus nets on a printed circuit board. FIGS. 2 and 3 are diagrams illustrating disturbances in the bus/net. FIG. 4 is a block diagram of an apparatus according to an embodiment of the present invention. Figure 5, 6th rf! J is a diagram illustrating a method of dividing a printed circuit board into regions. ■... Bus net, 2... Bus area, 3... Boundary line, 4... First fli'j area, 5... Second area, 13... Key human power device, 14 . . . CR'I' image display device, 15 . . . Photoplotter, 18 . . . Central processing unit, 19 . . . Storage device. Patent Applicant Yokogawa Electric Corporation Representative Patent Attorney Naotaka Ide

Claims (1)

[Scope of Claims] +11 A key-powered device, a CRT image display device, a photoplotter, and a central unit coupled to and controlling the key-powered device, the CRT image display device, and the photoplotter, respectively. and a storage device connected to the central processing unit, the central processing unit calculates a connection pattern on the printed circuit board according to the connection information on the printed circuit board given from the key human power device, and The figure of the calculation result is recorded in the storage device and the CRT
In the printed circuit board film sub-device configured to display on the image display device and output as a photomask to the photoplotter, the central processing unit connects the surface of the printed circuit board with wiring in the form of a bus net. including the bus area to be used and this bus area on the boundary line,
The area is divided into a first area and a second area whose boundary line crosses the wiring direction, and connection patterns are set in the order of the first area, the bus area, and the second area. A printed circuit board design device characterized by being configured as follows.