JPH0245881A - Method for wiring printed wiring board - Google Patents

Abstract

PURPOSE:To make a wiring work efficient and to shorten a design time by temporarily holding an easy hold segment, holding a segment to be change based on a temporary holding signal, moving the wiring part to the other area in which a wiring density is low, and executing a necessary wiring change. CONSTITUTION:A segment 22-1b (easy hold segment) positioned in the area with the low wiring density is selected, a cursor 23 is moved onto the segment (easy hold segment) 22-1b, and the segment 22-1b is temporarily held. Next, the cursor 23 is moved to the vicinity of a segment 22-1a to be originally changed or onto the line, and based on the temporary holding signal, the segment 22-1a positioned on the same line as the segment 22-1b is automatically held. Next, the cursor 23 is moved to the other area with the low wiring density, a diagonal segment 22-1c is drawn, next, a vertical segment 22-1d is drawn by the movement of the cursor 23, thereafter, a diagonal segment 11-1e is drawn, a connection is executed, and thereby, the necessary wiring change is completed.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a wiring method for printed circuit boards such as analog printed circuit boards, digital printed saw boards, flexible printed circuit boards, and hybrid printed circuit boards. The present invention relates to a wiring method suitable for revising a part of the .

[Prior art]

2. Description of the Related Art As various electronic devices develop and become more sophisticated and multi-functional, the circuit configurations of the various printed circuit boards 1 to substrates used therein tend to become more and more complex and multilayered.

In order to cope with this problem, automatic wiring of printed circuit boards has been proposed using various wiring methods such as the maze method and the line segment search method. However, in reality, part of the wiring is often changed after automatic wiring. Currently, the wiring is changed manually one by one by an operator while looking at a complicated wiring diagram displayed on a graphic display.

[Problem to be solved by the invention]

During this modification, especially when changing wiring in an area with high wiring density, the wiring is close to each other, so it is necessary to hold wiring parts other than the wiring parts that should be held for the change. Changes are often made. This is caused not only by the operator's operational error but also by the poor positioning accuracy of the cursor on the display screen used for making changes.

Furthermore, in order to prevent this from occurring, it is necessary to accurately visually select the wiring portion to be changed from a nearby high-density wiring area. This not only makes the operator's work very physically and mentally demanding, but also has drawbacks such as very low work efficiency.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a printed circuit board wiring method that eliminates the drawbacks of the prior art as described above, and improves the efficiency of wiring work and shortens design time.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention provides a method for changing other wirings among a large number of wirings created based on connection information and displayed on the display surface of a display. When changing a wiring part in a high-density wiring area where parts are close together, move the cursor on the display screen to an easy-to-hold line segment in a low-density area that is far away from other wiring. , the first step is to temporarily hold the easy-to-hold line segment, and the next step is to move the cursor near the wiring part to be changed to determine which part of the wiring should be changed based on the temporary hold signal. and a second step of holding the line segment.

The present invention is characterized in that it includes a third step of moving the main held wiring portion to another area with low wiring density and performing a desired wiring change.

〔Example〕

Next, a wiring method for a printed circuit board according to an embodiment of the present invention will be explained using the drawings. FIG. 1 is a block diagram for explaining the basic system configuration of an automatic wiring device according to an embodiment, FIG. 2 is a flowchart for explaining the processing operation of the automatic wiring device, and FIG. 3 is an example of a printed circuit board. A circuit diagram, Fig. 4 is a wiring diagram of a printed circuit board formed based on the circuit diagram, Fig. 5 is a diagram for explaining a specific example of automatic wiring, and Figs. 6 to 11 are examples of wiring changes. FIG.

First, the overall basic nitric acid in the CAD/CAM system will be explained using FIG. As shown in the figure, this system is broadly divided into a central processing unit 1, a storage device 2 consisting of a magnetic disk device, an optical disk device, etc.
, an NC tape making device 3, an automatic drawing machine 4, and work stations 5a and 5b. In this embodiment, the workstation 5a is permanently installed and the workstation 5b is for expansion.

Specifically, the NC tape creation device 3 includes a keyboard 6
, a printer 7, a paper tape puncher 8, and the like. Further, the workstation 5 specifically includes a system console 9, a color graphic display 10, a digitizer 11, and a command key 12.
It is composed of etc. The connection relationship of each device is as shown in the figure.Next, the processing flow of the DigiMole circuit CAD system will be explained using FIG. First, step (hereinafter, S
It is abbreviated as ) 1, the entire logic circuit diagram to be designed is created. Next, in order to realize this logic circuit by dividing it onto a plurality of printed circuit boards, logical division is performed in S2, and based on this, a partial logic circuit diagram is created for each printed circuit board in S3.

Next, in step 84, if the logic circuits are described at the gate level, gate allocation is performed to create them on corresponding IC chips. After that, in S5, the game (
・Place and fix the assigned IC chip (package) on the printed circuit board. Since this component placement greatly affects the ease of later wiring design, interactive layout design is performed using a graphic display.

At the gate allocation stage described above, the relative positional relationship of the IC chips (packages) has not been determined, so the allocation of gates within the component has not been determined. After 86 component placements are completed, gate positions within each IC chip (package) are determined and pin assignments within the IC chip (package) are performed (S6).

Next, in 87, wiring design is performed. Since the detailed operation will be explained later, the explanation of the wiring operation will be omitted here. As far as designing by automatic wiring is concerned, there are almost no wiring mistakes, but when the wiring is corrected (changed) using a graphic display after automatic wiring, it is done by one person, so there is a possibility that mistakes may be made. For this reason, in S8, for example, inspection for short circuits and open failures between wirings, and checking the spacing between patterns are performed. And finally S
In step 9, create artwork data.

Logical information is extracted from this and matched with input logical information.

Next, a specific example of the automatic wiring method will be described.

FIG. 3 is an example of a circuit diagram of a printed circuit board to which wiring is to be performed. In this figure, CN1 and CN2 are connectors,
IC1, IC2 and AND1 are IC chips, and small Arabic numerals placed around each electronic component indicate the pin number of each element.

Based on the circuit diagram drawn on this paper, create the following wiring information.

r CNI (1) CNl (2) CNI (3) IC1(it) IC1(I 0) ANDI (3) IC2(11) =IC1(1) =IC2(2) =AND1(2) =IC2(1) =ANDl (1) =IC2(3) =CN2 (1)J The wiring information obtained in this way is input to an automatic wiring device for printed circuit boards, and this wiring device performs the following based on the wiring information.
- Wire using wiring layers higher than the wiring layer. Note that wiring between layers is connected using through holes to avoid short circuits. Based on the above-mentioned wiring information, a wiring diagram as shown in FIG. 4 is created. The 0 mark in the figure indicates the position of the pin of each element, the mark ・ indicates the position of the through hole, and the solid line indicates the front side wiring.
The dotted lines indicate the backside wiring, CNI, IC1, etc. indicate the names of the electronic components to be placed, and the rectangular portions indicate the positions of the electronic components. This wiring diagram is drawn on a photosensitive film in actual size or variable magnification to obtain a visualized wiring diagram of the printed circuit board.

When creating a wiring diagram based on the above-mentioned wiring information, decide the direction in which the wiring should proceed, such as from the left to the right of the printed circuit board, or from the top to the bottom. And instead of wiring a single wire from beginning to end as in the past, for example, connectors and ICs mounted on printed circuit boards.
The distribution of pins (connection points) of electronic components such as chips (the placement positions of the electronic components have already been determined) in the wiring direction is taken. Next, all wiring in the section from the wiring start position to the first target position is performed, with the position where the distribution of pins (connection points) is high as the target position. Next, perform all wiring for each section from the first connection target position to the next second connection target position,
Wiring is carried out by sequentially repeating the connection between the connection target positions until the final connection end point.

Note that, for example, if there is no pin to connect at the second connection target position and there is a pin at the next third connection target position, a temporary target is provided at the second connection target position and the connection from the first connection target is made. The temporary target is connected, and in the first stage, wiring is performed between the temporary target and the third connection target. Of course, if there is a pin (target) to be connected before the connection target position that we are aiming for this time, we will wire up to that point.

After wiring including the above-mentioned temporary target to a predetermined target position, if it is possible to shift electronic components such as IC chips in the opposite direction to the direction in which they have already been wired, it is better to shift them.

This is particularly effective when two wires are wired between 0.1 inches, so-called two-wire logic between pins, but it can also be applied when one or three or more wires are wired between 0.1 inches.

Of course, if there is enough space for the printed circuit board.

You don't have to send it.

Next, a specific example of two logic wiring lines between pins will be explained using FIG.

One pin A of a normal IC chip consists of four logic lattices A, 口, C, and 2. ). As shown in the figure, when wiring from pin A at the nth target position to pin B at the next (n+1)th target position, if the wiring direction is set in advance It comes out from the upper right corner A of the logic grid and enters the lower left corner 2 of the logic grid at pin B (wire 1).

Regarding the wiring that passes through the section between the n-th target position and the (n+1)-th target position, a temporary target C is provided at the n-th target position, and the
A temporary target D is provided at the (n+1)th target position, and wiring is provided between these temporary targets C and D (wiring ■).

In this way, when wiring from one temporary target to the next temporary target, it is possible to have a directionality such as whether to maintain the same Y coordinate, or to go up as a whole, or to go down on the contrary.

When the wiring is completed to the (n+1)th target position, the pin at the (n+1)th target position is
Pack it as much as possible on the side opposite to the wiring direction X. However, if the pins of the electronic component at the n-th target position and the (n+1)-th target position belong to the same component, they cannot be brought together. At that time, when the pin of the electronic component at the nth target position is moved to the opposite side to the wiring direction, at the same time, the pin of the electronic component at the (n+1)th target position is also moved by the same dimension to the side opposite to the wiring direction. I'll leave it to you.

In the initial arrangement of electronic components, it is sufficient to spread them out loosely and place them in their approximate positions.

Through-holes also allow the use of smaller microvias than conventional ones.

Next, changes in wiring will be specifically explained using FIGS. 6 to 11.

Assume that a wiring diagram as shown in FIG. 6 is obtained by automatic wiring. In the figure, 20 is an IC chip to be connected, 21 is a connection pin of the IC chip 20, and 22 is a wiring that connects each electronic component such as the IC chip 20. In order to avoid complicated illustrations, only a few are shown in the drawing. Although this is not the case, a large number of wires 22 are actually drawn between the electronic components. 23
is a cross-axis cursor on the display surface of a graphics display.

In the wiring diagram of FIG. 6, a case will be described in which the position of the line segment 22-1a of the wiring 22-1 among the many wirings 22 is changed.

This line segment 22-1a to be changed is located in a high-density wiring area and is in close proximity to a portion of other wiring. It would be fine if this line segment could be held directly with the cursor 23, but since the vicinity of the line segment 22-1a is a high-density wiring area, other wiring 22 may be held due to incorrect operation or poor positioning accuracy of the cursor 23. There is a risk of holding.

In this way, if the wiring 22 that does not need to be changed is held and changed, the wiring becomes incorrect, and it takes time to hold the wiring again.

Therefore, in the present invention, the line segment 22-
1a is not directly held, and as a first step, as shown in FIG. Line segment 22-1b (
22-1b, move the cursor 23 onto the line segment (easy-hold line segment) 22-1b, and select the line segment 22-1b.
Temporarily hold 1b. The line segment 22-1b held in this way has a different display color than other line segments (in the drawing, the held state is drawn with a thick line to indicate that the display color is different), and the operator This allows you to easily check the held line segment.

Next, as a second step, as shown in FIG. 8, the cursor 23 is moved near or on the line segment 22-1a to be changed. Then, based on the temporary hold signal of the previously held line segment 22-1b, the line segment 22-
The line segment 22-1a that is on the same line as 1b is automatically held, and the display color of the line segment 22-1a changes (
In the drawing, the held state is drawn with thick lines. )
, it can be easily confirmed that this hold has been made.

Next, as a third step, as shown in FIG. 9 in this held state, move the cursor 23 to another area with low wiring density, draw a diagonal line segment 22-1c, and then As shown in FIG. 10, the vertical line segment 22-1d is drawn by moving the cursor 23, and then the diagonal line segment 1l-Is is drawn and connected as shown in FIG. 11, thereby completing the desired wiring change. .

Although this embodiment describes the case where the wiring is changed on the same plane, the present invention is not limited to this, and can also be applied, for example, to the case where the wiring is changed from one side of a printed circuit board to the other side. be able to.

The present invention relates to a wiring method for a printed circuit board, and if the wiring holding method of the present invention is used when checking the wiring, the checking work can be performed easily and accurately.

[Effects of the Invention] Since the present invention has the above-described configuration, wiring changes can be performed very easily, and the wiring work can be made more efficient and the design time can be shortened.

[Brief explanation of the drawing]

FIG. 1 is a block diagram for explaining the basic system configuration of an automatic wiring device according to an embodiment of the present invention, FIG. 2 is a flowchart for explaining the processing operation of the automatic wiring device, and FIG. 3 is an example. The circuit diagram of the printed circuit board 1, FIG. 4 is the wiring diagram of the printed circuit board formed based on the circuit diagram,
Figure 5 is an explanatory diagram for explaining a specific example of automatic wiring, Figures 6, 7, 8, 9, 10, and 1.
FIG. 1 is an explanatory diagram for explaining an example of changing the wiring. 20...IC chip, 21...Connecting pin, 22...Wiring, 22-1a...Line segment to be changed, 221b... Easy hold line segment, 2
2-1c, 221e...diagonal line segment, 22-1d
... Vertical line segment, 23 ... Cursor.

Claims (1)

[Claims] Among the many wires created based on the connection information and displayed on the display surface of the display, among the wires that are subject to wiring change, other wire portions are close to each other. When changing a wiring part in a high-density wiring area, move the cursor on the display screen to an easy-to-hold line segment that is far away from other wiring, and click the first button to temporarily hold that easy-to-hold line segment. a second step of permanently holding the line segment to be changed in the wiring based on the temporary hold signal by moving the cursor near the wiring part to be changed; A method for wiring a printed circuit board, comprising: a third step of moving the held line segment to another area with low wiring density to perform a desired wiring change.