JPH02161569A - Method for wiring of printed board - Google Patents

Abstract

PURPOSE:To make wiring work efficient and to shorten a design time by forming an inclined short wiring part unitedly with the formation of a wiring part at the time of connecting the connection part of a wiring not shown in a virtual logical grating on a wired board to the node of the wired board. CONSTITUTION:A start point 32 is not shown on the virtual logical grating 31 and a wiring segment 33a is the initial wiring segment having the start point 32. A wiring program is formed so that the inclined short wiring part 33b connecting the start point 32 of the initial wiring segment to the center part of a through-hole 30 is formed simultaneously with the formation of the initial wiring segment. The connecting method for the initial wiring segment having the start point can be similarly used for the connection between a final wiring segment having an end point and a node such as a through-hole.

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 circuit boards, flexible printed circuit boards, and hybrid printed circuit boards, and particularly relates to a wiring method for printed circuit boards such as analog printed circuit boards, digital printed circuit boards, flexible printed circuit boards, and hybrid printed circuit boards. The present invention relates to a wiring method that allows a good connection between a connection end (start point or end point) of a wiring that does not lie on a logic lattice and a connection point of a wiring board such as a through hole.

(Prior Art) As various electronic devices develop and become more sophisticated and multi-functional, the circuit configurations of the various printed circuit boards used therein also tend to become 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, the start point or end point of a wiring part that includes a start point or end point may not be on the logic grid on the wiring board. It is necessary to connect the start point or end point and the through hole with a short sloping wiring section, which is particularly difficult to operate because the length of the wiring section is extremely short. There are many imperfections.

In order to prevent this from happening, wiring must be done carefully, which not only makes the operator's work extremely demanding both physically and mentally, but also reduces work efficiency. It has some very bad drawbacks.

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 in which a start point or an end point of a wiring created based on connection information and displayed on a display surface of a display is placed on a virtual logical grid on a wiring board. When connecting a wiring part that is not connected to a connection point such as a through hole on a wiring board, a slanted short wiring part that connects the start point or end point and the corresponding connection point is formed in the wiring part. They are characterized in that they are sometimes automatically formed into one piece.

〔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. 12 is a diagram for explaining automatic connection between a wiring portion including a start point and a through hole.

First, the overall basic configuration of the CAD/CAM system will be explained using FIG. As shown in the figure, this system is roughly divided into a central processing unit 1, a storage bag W2 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. 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 ) In 1, the entire logic circuit diagram to be designed is created. 6 Next, in order to realize this logic circuit by dividing it onto multiple printed circuit boards, logic division is performed in S2, and based on this, in S3. A partial logic circuit diagram is created for each printed circuit board.

Next, at 84, if the logic circuits are described at the gate level, gate assignment is performed to assign them to corresponding IC chips. Thereafter, in S5, the IC chip (package) to which the gate has been assigned is placed and fixed 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 wiring is corrected (changed) using a graphic display after automatic wiring, there is a possibility that mistakes may be made because it is done manually. 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 8
In step 9, artwork data is created, logical information is extracted from it, and it is matched with input logical information.

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

FIG. 3 is an example of a circuit diagram of a printed circuit board to which wiring is to be performed. In this figure, CNI and CN2 are connectors,
ICI, IC2, and ANDI 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) = IC1 (1) CNI
(2)=IC2(2) CNI (3)=AND1 (2)IC1(11)
=IC2(1) ICI(10)=AND1(1)ANDI
(3): IC2 (3) IC2 (11) = CN2 (1) J The wiring information obtained in this way is input to an automatic wiring device for printed circuit boards, and based on the wiring information, this wiring device
- 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 1: For example, if there is no pin to connect at the second connection target position, but 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 is made from the first connection target. The temporary target is connected, and in the secondary 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.

For this, two wires are wired between 0.1 inches. This is particularly effective in the case of so-called two-wire logic between pins, but it can also be applied to cases where 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 bins will be explained using FIG.

One pin A of a normal IC chip consists of four virtual logic lattice areas A, 2, 2 (here, a virtual logic lattice is a lattice virtually created on a printed circuit board). 6 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, the predetermined wiring direction is
Then, it comes out from the upper right part A of the logic lattice area of pin A,
It enters the lower left corner of the logic grid area of pin B (wire I). 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 a temporary target C is provided at the n-th target position.
1) A temporary target D is provided at the th target position, and wiring is established 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. of course,
If the pins of electronic components 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 opposite side 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.

FIG. 12 is a diagram for explaining automatic connection between a wiring portion including a starting point and a through hole according to an embodiment of the present invention.

In this FIG. 12, 30 is a through hole, 31 is a logical lattice virtually created for wiring operation, 32 is a starting point that is not on the virtual logical lattice 31 as shown in the figure,
33a is the first wiring segment having this starting point 32, and when forming this first wiring segment 33a, an inclined short wiring portion 33b connecting the starting point 32 and the center point of the through hole 30 is formed at the same time. The wiring program looks like this.

The appropriate inclination angle of the inclined short wiring portion 33b is, for example, 45 degrees in order to obtain a neatly finished wiring, but it is possible to change this inclination angle as necessary.

In addition, in the embodiment shown in FIG. 12, the case of the first wiring segment having a start point has been explained, but the above-mentioned wiring also applies in the case of connection between the last wiring segment having an end point and a connection point such as a through hole. The method used is self-explanatory.

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. Only a few lines are shown in one drawing to avoid complicated illustrations. 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 located in a low density area
(easy hold line segment), move the cursor 23 onto the line segment (easy hold line segment) 22-1b, and
-Temporarily hold tb. 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-
Line segment 22-! which is on the same line as 1b! -1a is automatically held, and this time the display color of the line segment 22-1a changes (in the drawing, the held state is drawn with a thick line), making it easy to confirm that the line segment 22-1a is actually held.

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 and draw a diagonal line segment 22-1 c. Next, as shown in FIG. 10, by moving the cursor 23, a vertical line segment 22-1d is drawn, and then, as shown in FIG. 11, a diagonal line segment 1l-1e is drawn and connected to complete the desired wiring change. do.

Although this modification example has been described with respect to the case where the wiring is changed on the same plane, the present invention can also be applied, for example, to the case where the wiring is changed from one side of the printed circuit board to the other side.

Additionally, when changing the wiring position of the first wiring segment with a start point or the last wiring segment with an end point as described above, holding that wiring segment also holds the slanted short wiring part. If you use this method, the modification work will be easier and more accurate.

[Effects of the Invention] Since the present invention has the above-described configuration, the wiring work can be performed very easily, the wiring state is clean, 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. A circuit diagram of a printed circuit board, FIG. 4 is a wiring diagram of a printed circuit board formed based on the circuit diagram, FIG. 5 is an explanatory diagram for explaining a specific example of automatic wiring, and FIG.
Figures 7, 8, 9, 10 and 11
The figure is an explanatory diagram for explaining an example of changing the wiring, and FIG. 12 is a diagram for explaining automatic connection between the starting point of the first wiring segment and the through hole. ment, 33b...Slanted short wiring part. 30...Through hole, 31...Virtual logical lattice. 32... Start point, 33a... First wiring segment Fig. 4 Fig. ND1 Fig. Fig. U Fig. Fig. Fig. 11 Fig. 10 Fig. 2゜2゜ No. 12 figure

Claims (1)

[Claims] Among the wiring patterns created based on the connection information and displayed on the display surface of the display, the wiring part where the start point or end point of the wiring does not lie on the virtual logic grid on the wiring board can be connected to the wiring board. When connecting a point, an inclined short wiring portion connecting the start point or end point and the corresponding connection point is automatically formed integrally when forming the wiring portion. A printed circuit board wiring method characterized by: