JP2976354B2 - Printed wiring board repair method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mount component (SM).
D: A method for repairing a printed wiring board equipped with Surface Mounted Devices , especially for surface mounting.
Cut the pattern located on the underside of the pad
Printed wiring to avoid and change wiring pattern
The present invention relates to a method for correcting a substrate.

[0002] CAD (Computer Aided Design) to the printed circuit board designed using the system, if it becomes necessary circuit changes, the wiring pattern cut part及
Fine connection points instruction drawing of the printed wiring board such as output corrected <br/> process performed automatically by the printed circuit board by a computer
Automatic correction methods are known. However, in recent years
Mount on printed wiring board according to density mounting requirements
Increasing the number of pins, miniaturization, narrowing of pitch, etc.
With the adoption of many such components,
Automatic repair of printed wiring boards is also becoming increasingly complex and difficult
I came. In particular, printed wiring with components for surface mounting
In the automatic correction process of the board, the SM of the printed wiring board
Pre that can avoid pattern cutting instruction under D pad
There is a need for a method for repairing printed wiring boards.

[0003]

2. Description of the Related Art Printed wiring on which components for surface mounting are mounted
The cutting position of the wiring pattern in the automatic board repair process
To determine the section of the wiring pattern to be cut
By setting both ends of the
Depending on the antenna length (pattern cut length)
The cutting position was determined.

FIG . 5 shows a conventional cutting of a wiring pattern under a pad.
11 and 12 are first and second surface mounts.
Use _{component, 13 1, 13 2, ...} , 13 n is unit for the first surface mount
SMD pad for connecting to product 11, 141 _, 142 _, ... _,
14 _n is an SM for connecting to the second surface mounting component 12.
D-pad, 15 is connected to the SMD pad 13 ₁ surface
Pattern, 16 is connected to the SMD pad 14 ₁ surface
Pattern, 17 is a via connected to the surface pattern 15,
18 is a via connected to the surface pattern 16, 19 is a via
It is an inner layer pattern connected between 15 and 16.

In correcting a wiring pattern, an inner layer pattern
If it becomes necessary to cut off the
As described above, the automatic repair of the printed circuit board
The pattern is cut according to the antenna length preset on the computer.
To determine the cutting position, make sure that the cutting position is just below the SMD pad.
It may be the inner layer pattern 19. For example,
Cutting position 20 immediately below the to SMD pad 14 ₂ is designated
Sometimes. This cutting position, the SMD pad 14 ₂
Since it is within the shape, it is impossible to cut the inner layer pattern 19.
Become. Especially when the surface mounting components 11 and 12 are mounted.
In this case, a cutting process using a laser or the like becomes impossible.

[0006]

SUMMARY OF THE INVENTION Conventional wiring patterns
In determining the cutting position in the correction method, the cutting target
Pattern is running under the SMD pad
It is not to determine whether or not it is an application. Therefore,
Activate the automatic correction process of the calculator and cut the finger under the pad.
Check if there is any
Extra computer resources
Sources and man-hours increase. Also under the pad with automatic correction processing
The cutting of the wiring pattern is indicated by the mark
In this case, the cutting instruction mark is hidden in the pad,
In some cases, it is difficult to search for a cut portion on a drawing.
Also, actually cut the wiring pattern under the pad.
Is virtually impossible. Wiring pattern under the pad
If a cut is instructed, another cutable position is
Search on the drawing and manually calculate the cutting position again by hand
Must be processed. Therefore, the manual
Typing errors due to file processing occur frequently, making cutting work difficult.
You. There were many problems.

The present invention solves such problems of the prior art.
The SMD pad should be
By recognizing it as a turn disconnection prohibited area, SM
Aim to avoid pattern cutting instruction under D pad
Target.

[0008]

The present invention is shown in FIG.
A pad with pads for mounting surface mount components
Information on the shape and position of the pads on the printed wiring board
Information and information about the pattern cutting prohibited area.
A first information input step (first information input step 1)
The information of the wiring pattern and the net
Input second information input process (second information input step 2)
When, at the first information input step and the second information input process
Based on the information entered in
First determining step of determining the cutting position in the
Decision step 3) and the cutoff determined by the first decision process
On the same net when the cutting position is within the pattern cutting prohibited area
Search for a wiring pattern that is not in the pattern cutting prohibited area
A second decision to determine a cutting position for the wiring pattern
(Second decision step 4). this
If the pattern cutting prohibited area is the same as the pad shape
Can be set.

[0009]

[Action]The processing steps in the present invention include: To be modified
Mounting of surface mount components on printed wiring boards
Determine nothing. When surface mount components are mounted,
Extract the number. Package of surface mount components to be mounted
Search for pad type and use SMD pad from pad table
Extract the shape of the pattern and prohibit pattern cutting of the same shape as that shape.
Stop area is defined on all layers of the printed circuit board, and
To memorize. The total number of targets
Information on all wiring patterns and nets to determine the cutting position.
Set. For the cutting position determined above,
Judgment is within the SMD pad shape defined in
I do. The cutting position is included in the shape of the SMD pad
If there is, the wiring pattern on the same net
Check again for wiring patterns that are not included in the MD pad shape.
The cutting position is determined on this wiring pattern.
The position to be cut is stored, and the above processing is performed for the number of changed nets.
Repeat the process.

Therefore, according to the present invention, under the SMD pad
Since the instruction to cut the wiring pattern is automatically avoided,
Confirmation of cutting position and manual recalculation of cutting position
Input instructions are not required, and printed circuit
The board can be repaired quickly.

[0011]

2 to 4 show an embodiment of the present invention.
FIG. 2 is for avoiding the disconnection of the wiring pattern under the pad.
FIG. 3 shows a method of determining a new cutting position by using the SMD package.
FIG. 4 shows a method of recognizing shape information and arrangement information of a file.
Shows a raw chart.

In FIG . 2, the same reference numerals as those in FIG. 5 denote the same parts.
The shaded area is the pattern cutting prohibited area.
You. That is, the SMD pads 13 ₁ ,..., 13 _n , 1
4 ₁ ,... Pattern cutting of the same shape as the shape of 14 _n
A prohibited area is set. Therefore, the inner layer pattern 19 is not
The cutting position to be specified depends on the shape of the SMD pad.
In the figure, the whole pattern is cut except the prohibition area.
A cutting position 21 indicated by X is designated. That is, the cutting position 2
1 will not be under the SMD pad 14 ₂ . Also inner layer
Same if the pattern is running under other SMD pads
It is.

Prohibition of pattern cutting for SMD pad
When the area is automatically generated, as shown in FIG.
11 are arranged as shown in FIG.
You. That is, the part symbol, part number, pad number,
Placement coordinates, number of net connected to pad, pad
Enter the shape, pad figure information, pad formation layer, etc.
Correct processing is performed, and pattern cutting of round, rectangular, and other shapes is performed.
A prohibition area is automatically generated. Required for various figures in this case
For information on important shapes and dimensions, for example,
Can be given by the coordinates and radius of the center position indicated by +
You. In the case of a rectangle, the coordinates of the center position also indicated by + in the figure
And the length from the left end indicated by X1 to the center position and Y2
Given by the length from the top edge shown to the center position
Can be. Similarly, for other figures, the center position and one end
The position and the coordinate information that can
The shape of the SMD pad, that is, the pattern cutting prohibited area
Can be automatically generated.

As shown in the flowchart of FIG .
First, it is determined whether or not the surface mounting component is mounted (S1).
If so, as shown in FIG. 3, the SMD pad
It generates a sequence of data of have Nitsu, pattern disconnection warning
Define an area, store it in the computer (S2), and cut the pattern
All old wiring pattern information and old net information
Information is collected (S3). Calculator based on this information
Perform the necessary corrections above to determine the pattern cutting position
(S4). And the pattern cutting position is SMD pad
It is determined whether it is within the SMD pad or not (S5).
Is a wiring pattern other than SMD pads on the same net
The position of the button is searched (S6), and the above-described step (S4) is performed.
The process proceeds to determine the pattern cutting position. Also pattern cut
If the cutting position is not within the SMD pad,
The break position is stored (S7), and thereafter, the same as the number of net changes
The process is repeated (S8). To perform such processing
It is necessary to correct the wiring pattern of the printed wiring board.
It is.

[0015]

As described above, according to the present invention,
Automatic correction of printed wiring boards with components for surface mounting
In processing, at least the position and shape of the SMD pad
By setting the pattern cutting prohibited area according to the
The cutting instruction of the wiring pattern under the SMD pad
Can be avoided. Therefore, such a disconnection instruction
There is no need to confirm that no
And instruct the computer again on the pattern cutting position to process
Since there is no need, computer resources and man-hours can be saved.
In addition, for repair work of printed wiring board by circuit change
There is an advantage that can be dealt with quickly.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of the present invention.

FIG. 2 is a diagram showing a method of determining a new cutting position by avoiding cutting of a wiring pattern under a pad according to one embodiment of the present invention.

FIG. 3 is a diagram illustrating a method of recognizing shape information and arrangement information of an SMD pad according to one embodiment of the present invention.

FIG. 4 is a flowchart showing a processing procedure of the method of the present invention according to one embodiment of the present invention.

FIG. 5 is a diagram exemplifying a conventional cutting of an under-pad wiring pattern.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st information input stage 2 2nd information input stage 3 1st determination stage 4 2nd determination stage

Claims (2)

(57) [Claims] 1. A shape of the pad of the printed wiring board having a pad for mounting the component for surface mounting, and information about the position, a first information input process for inputting the information about the pattern cut prohibition region, A second information inputting step of inputting information of a wiring pattern to be cut and information of a net; and a first information inputting step and a second information inputting step.
Based on each information input at a first determination process of determining at Keru cutting position to a wiring pattern becomes blown object
If, during the pattern on the same network switch of the cutting position determined by the determining process of the first is the pattern cut prohibition region
Including a second determination process of determining the cutting position on the wiring pattern by searching no wiring pattern sectional prohibition region
A method for repairing a printed wiring board . Wherein said pattern cut prohibition region with respect to the respective wiring patterns are printed circuit group according to claim 1, characterized in that it is set to be the same as the shape of the pad
Board correction method.