JPH07160756A - Graphic distance confirming method for design of printed circuit board - Google Patents

Abstract

PURPOSE:To surely and easily confirm the space between two graphics different by clearances or the like, for example, between a pad graphic and a solder resist aperture graphic, the width or the pitch of plural graphics having the same shape, or the like. CONSTITUTION:An operator sees a pad graphic 1 and a solder resist aperture graphic 2 displayed on the display device of a CAD device to select segments 1a and 2a by operation of a tablet. A computer confirms pattern graphics to which selected segments 1a and 2a belong. The computer calculates the minimum distance (gap) between selected segments 1a and 2a based on pattern data of these graphics. The computer displays this gap value on the display device as the value of clearance C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for checking a graphic distance when designing a printed wiring board, and more specifically, a pad displayed on a screen of a display device when designing the printed wiring board using a CAD device. The present invention relates to a method for confirming the clearance between a figure and a solder resist opening figure.

[0002]

2. Description of the Related Art A solder resist applied on a substrate for improving insulation resistance and withstand voltage between conductors of a printed wiring board has a great influence on soldering quality of components during assembly. Therefore, in a surface-mounted printed wiring board, attention must be paid to the clearance between the component mounting pad and the solder resist. That is, if the setting is incorrect, the resist may be applied onto the pad to prevent the solder from being applied, or the conductor in the vicinity of the pad may be exposed to cause a short circuit in the soldering process due to an error in manufacturing the printed wiring board. For this reason, when designing a printed wiring board using a CAD device, the clearance is checked as needed.

Generally, when a printed wiring board is designed by a CAD device, wiring pattern data including the shape of the pad and solder resist pattern data having an opening shape corresponding to the pad are created. When creating a figure of an opening of a pad or a solder resist by a CAD device, each pattern data is line segment data with width (line data), arc data with width (arc data), and position data with width (flash data). Stored in memory. Then, the clearance between the pad figure created by the CAD device and the opening figure of the solder resist is checked while observing the figure displayed on the display. For example, when checking the clearance C between the circular pad figure 41 and the same circular solder resist opening figure 42 as shown in FIG. 6A, the operator uses a tablet or the like equipped in the CAD device to perform padding. The figure 41 and the opening figure 42 are designated by the cursor on the screen. By this instruction, data such as the coordinate values and radii of the pad graphic 41 and the opening graphic 42 are displayed on the screen. Then, the operator calculated the clearance C based on the data.

[0004]

However, as shown in FIG. 6 (b).
When checking the clearance C of the quadrangular pad figure 43 and the opening figure 44 as shown in, the data displayed on the screen is compared with the circular pad figure 41 such as the center coordinates, the position coordinates of the four corners, and the width dimension. Is increasing.
Further, when the pad figure is formed by superposing a plurality of figures, the number of data is further increased. Therefore, in the above-described checking method, when the operator calculates the clearance C while looking at the data displayed on the screen, there is a problem that the clearance C may be mistaken by mistakenly looking at the data or making a calculation error. is there. There is also a problem that it is troublesome to calculate the clearance C by looking at the data displayed on the screen, which takes time and labor.

The above-mentioned checking method is applied not only for checking the clearance C between the pad figure and the solder resist opening figure but also for checking the width of the pad figure and the pitch between the pad figures. However, also in checking these distances, there is a problem in that a calculation error or a calculation takes time as in the above.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide an interval between two figures having different clearances between a pad figure and a solder resist opening figure, and a plurality of same shapes. It is an object of the present invention to provide a method of checking a figure distance when designing a printed wiring board, which can surely and easily check the width or pitch of a figure.

[0007]

In order to solve the above-mentioned problems, the invention described in claim 1 is a distance between figures displayed on a screen of a display device when a printed wiring board is designed using a CAD device. A pattern figure to which one line segment selected respectively from different figures by the operation of the selecting means is confirmed, and the selected line segments are selected based on the pattern data of each figure. After calculating the minimum distance, the minimum distance is displayed on the screen of the display device.

The invention according to claim 2 is a method for confirming the distance of a graphic displayed on the screen of a display device when designing a printed wiring board by using a CAD device, and a method of selecting means. The pattern figure to which one line segment selected from each figure that constitutes the pattern data of different layers by the operation is confirmed, and the minimum distance between the selected two line segments based on the pattern data of each figure After calculating, the minimum distance is displayed on the screen of the display device.

[0009]

According to the first aspect of the invention, the operator selects one line segment by operating the selection means while observing the pattern figure displayed on the screen of the CAD device. 1 selected from different figures by computer
The pattern figure to which the line segment of the book belongs is confirmed. continue,
The computer calculates the minimum distance between the two selected line segments based on the pattern data of each of these figures. Then, the minimum distance is displayed on the screen of the display device. Therefore, unlike the conventional method in which the operator calculates the distance (clearance) based on the data such as the coordinate value of the graphic displayed on the screen of the display device, the distance can be confirmed reliably and easily.

According to the second aspect of the invention, the same operation as described above is performed with respect to the pattern graphic of different layers such as the pad pattern and the solder resist pattern.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to FIGS. First, the electrical configuration of the CAD device will be briefly described.

As shown in FIG. 2, the CAD device 21 comprises a microcomputer 22, a keyboard 23, a tablet (selection means) 24, a hard disk driver 25 and a display (display device) 26.

The microcomputer 22 has a CPU (central processing unit) 27, and the CPU 27 has a ROM (read only memory) 28 and a RAM (random memory).
Access memory) 29. ROM 28
The control program is stored in the
It operates according to the control program stored in the OM 28. The RAM 29 temporarily stores the arithmetic processing result of the CPU 27 and the data input by the keyboard 23 and the tablet 24.

The keyboard 23 and the tablet 24 are connected to the CPU 27 via an input interface (not shown), and perform operations and inputs when designing a printed wiring board. Hard disk driver 25 is CP
U27 is connected via an input / output interface (not shown) and reads data from the hard disk 30 mounted in the hard disk driver 25, the hard disk 3
Data can be written to 0. The hard disk 30 has a role as a database when designing a printed wiring board, and stores wiring pattern data, solder resist pattern data, etc. designed according to a control program in separate groups. The display 26 is connected to the CPU 27 via an output interface (not shown), displays various data when designing a printed wiring board, and can simultaneously display wiring pattern data and solder resist pattern data. ing.

Further, the CPU 27 drives the hard disk driver 25 to store the wiring pattern data and the like created based on the input of the keyboard 23 and the tablet 24 in the hard disk 30. When the data is stored in the hard disk 30, the CPU 27 assigns an identification (ID) number to each pattern figure of each data.

The CPU 27 is operated by the operator on the tablet 24.
When a line segment of a graphic displayed on the display 26 is selected by using, the graphic data is read from the hard disk 30 based on the ID number corresponding to the graphic. Further, the CPU 27 can specify the line segment selected from the read graphic data. Furthermore, C
The PU 27 calculates the distance between the pad figures of the wiring pattern data, the clearance between the pad figure and the opening figure of the solder resist pattern data, etc. based on the data of the line segment selected from the read figure data. Has become. Further, the CPU 27 controls the display 26 to display the calculation result such as clearance.

Next, the graphic created by the CAD device 21 will be described. As shown in FIG. 1, on the display 26, a pair of square pad figures 1 forming a part of the wiring pattern data are displayed at predetermined intervals, and a rectangular shape forming a part of the solder resist pattern data. An opening figure 2 is displayed so as to surround both pad figures 1. The pad figure 1 is a hard disk 3 as position data (flash data) with a rectangular width.
It is stored in 0. The aperture figure 2 is stored in the hard disk 30 as line segment data with width (line data). A predetermined clearance (0.15 mm in this case) C is provided between each pad figure 1 and the opening figure 2. The wiring pattern graphic 3 arranged on each pad graphic 1 is stored in the hard disk 30 as line data.

Next, a method of confirming the clearance C between the pad figure 1 and the opening figure 2 created as described above will be described with reference to the flowchart of FIG. In step (hereinafter, step is referred to as S) 1, the CPU 27 displays the display 2 based on the operation of the keyboard 23 by the operator.
Graphic data of the pad graphic 1 and the opening graphic 2 are displayed on the screen 6 as shown in FIG. In S2, the operator looks at the graphic displayed on the display 26 and sees the tablet 2
4 is used to move the cursor 4 to select the arbitrary position A of the line segment 1a close to the clearance C of the pad figure 1.
Subsequently, the cursor 4 is similarly moved using the tablet 24 to select the arbitrary position B of the line segment 2a of the opening figure 2 which is opposed to the line segment 1a of the pad figure 1.

Next, in S3, the CPU 27 determines the flash data of the pad graphic 1 based on the ID number of the pad graphic 1 corresponding to the selected line segment 1a and the ID number of the opening graphic 2 corresponding to the line segment 2a. It is searched whether the line data of the aperture figure 2 is stored in the hard disk 30. Subsequently, in S4, the CPU 27 confirms that both data are retrieved, and in S5, the flash data and the line data are stored in the hard disk 30.
Read from and write to RAM 29.

In S5, the CPU 27 confirms, based on the flash data stored in the RAM 29, which line segment of the outline of the pad figure 1 the coordinates of the arbitrary position A is located. Subsequently, the CPU 27 calculates the four corners of the flash data of the pad figure 1 and extracts the line segment 1a corresponding to the arbitrary position A by the coordinate value. Similarly, the CPU 27 confirms, based on the line data stored in the RAM 29, which line segment of the opening figure 2 the coordinates of the arbitrary position B is located. Subsequently, the CPU 27 calculates the four corners of the line data of the aperture figure 2 to calculate the line segment 2a corresponding to the arbitrary position B.
Is extracted with coordinate values.

Next, in S6, the CPU 27 confirms that the data of the two line segments 1a and 2a are extracted, and in S7, the two line segments 1a and 2a are based on the coordinate values of the line segments 1b and 2b. Calculate the minimum distance or gap between them.

Then, in S8, the CPU 27 causes the display 26 to display the calculated gap value as the clearance C value. In this way, confirmation of the clearance C between the pad figure 1 and the opening figure 2 is completed.

As described above, in this embodiment, the clearance C can be obtained by simply moving the cursor 4 to arbitrary positions A and B on the lines of the pad figure 1 and the opening figure 2 and selecting the line segments 1a and 2a. It is displayed on the display 26 by the calculation of the microcomputer 22. Therefore, it is not necessary for the operator to calculate the clearance C based on the coordinate data of the pad figure 1 and the opening figure 2 displayed on the display 26, so that the clearance C will not be mistaken due to a calculation error, and can be surely confirmed. You can In addition, the clearance C is set to the microcomputer 2
The calculation of 2 allows quick and easy confirmation.

Next, an explanation will be given by taking as an example a figure different from the above-mentioned pad figure 1 and opening figure 2. As shown in FIG. 4, this figure has a plurality (three in this case) of square pad figures 5 to 7 arranged at equal intervals. A wiring pattern graphic 8 is arranged on each pad graphic 5-7.

In order to confirm, for example, the pitch P of the pad figures 5 to 7 described above, the operator moves the cursor 4 displayed on the display 26 to move the cursor 4 displayed on the display 26 to an arbitrary position of the line segment 5a facing the pad figure 6 of the pad figure 5. Select A. Then, similarly, the operator moves the cursor 4 to select the arbitrary position B of the line segment 6a of the pad figure 6 that faces the pad figure 7.

Then, the CPU 27 causes the selected line segment 5
The flash data of the pad figures 5 and 6 corresponding to a and 6a are read from the hard disk 30 based on the ID number and written in the RAM 29. Next, the CPU 27 is a RAM
Based on the flash data stored in 29, it is confirmed to which line segment of the pad figure 5 the coordinates of the arbitrary position A are located, and the four corners of the flash data of the pad figure 5 are calculated to obtain the arbitrary position A. The corresponding line segment 5a is extracted by the coordinate value. Similarly, the CPU 27 confirms which line segment of the pad figure 6 the coordinate of the arbitrary position B is located on, and extracts the line segment 6a corresponding to the arbitrary position B by the coordinate value.

The CPU 27 then extracts the two line segments 5
The minimum distance between a and 6a, that is, the gap is calculated, and the value of the obtained gap is displayed on the display 26 as the value of the pitch P. In this way, pad figures 5-7
The confirmation of the pitch P of is completed.

Further, a figure different from the pad figure 1 and the opening figure 2 and the pad figures 5 to 7 will be described as an example.
As shown in FIG. 5, this figure is plural (in this case, three).
The square figures 9a to 9c are formed as one rectangular pad figure 10 in a state of being overlapped with each other. A wiring pattern graphic 11 is arranged on the pad graphic 10.

In order to confirm, for example, the width W of the pad figure 10 in the longitudinal direction, the cursor 4 displayed on the display 26 is moved so that the line figure in the width direction of the pad figure 10, that is, the square figures 9a and 9c. Line segments 10a, 10b
Select arbitrary positions A and B.

Then, the CPU 27 causes the selected line segment 10
The flash data of the square figures 9a and 9b corresponding to a and 10b are read from the hard disk 30 based on the ID number and written in the RAM 29. Next, the CPU 27
Based on the flash data stored in the AM 29, it is confirmed which line segment the coordinate of the arbitrary position A is located in the square figure 9a, and the four corners of the flash data of the square figure 9a are calculated to obtain the arbitrary position A. The corresponding line segment 10a is extracted by the coordinate value. Similarly, the CPU 27 confirms which line segment of the square figure 9b the coordinate of the arbitrary position B is located, and extracts the line segment 10b corresponding to the arbitrary position B by the coordinate value.

The CPU 27 then extracts the extracted line segments 1
The minimum distance between 0a and 10b, that is, the gap is calculated, and the value of the obtained gap is displayed on the display 26 as the value of the width W. In this way, confirmation of the width W of the pad figure 10 in which a plurality of figures are superimposed is completed.

As described above, in the present embodiment, not only the clearance C of the pad figure 1 and the opening figure 2, but also the pitch P of the plurality of pad figures 5 to 7 and the pad figure 10 in which a plurality of square figures are superimposed. The width W can be surely and easily confirmed only by moving the cursor 4 and selecting two line segments.

The present invention is not limited to the above-mentioned embodiments, but may be modified as follows, for example, without departing from the gist of the present invention. (1) In the above-described embodiment, after the line segments of the two figures are selected, the CPU 27 extracts the line segment data based on the pattern data of the figure corresponding to the selected line segment. Each time one line segment is selected, the CPU 27 may extract the data of the line segment.

(2) In the above embodiment, the tablet 24 is used as a device for moving the cursor 4, but a device such as a mouse or a trackball may be used instead. (3) The pad figure 1 and the opening figure 2 may be applied to shapes other than a square, a rectangle, and a circle, such as a polygon.

(4) In addition to the clearance C of the pad figure 1 and the opening figure 2, the pitch P of the pad figures 5 to 7, and the width W of the pad figure 10, a conductor pattern figure and a through-hole figure in the multilayer printed wiring board. It may be applied when confirming the intervals and the like.

(5) It may be applied to confirm the clearance between the pad figure and the solder resist opening figure when the component data of the semiconductor package to be mounted on the printed wiring board is created and registered in the library.

[0037]

As described in detail above, according to the present invention, the distance between two figures having different clearances between the pad figure and the solder resist opening figure, and the width or pitch of a plurality of figures having the same shape can be ensured. It has an excellent effect that it can be easily and easily confirmed.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a state in which a pad figure and a solder resist opening figure are created in an example of the present invention.

FIG. 2 is a block diagram showing an electrical configuration of a CAD device.

FIG. 3 is a flowchart showing a method of confirming a clearance between a pad figure and a solder resist opening figure.

FIG. 4 is a conceptual diagram showing a state in which a plurality of pad figures are created.

FIG. 5 is a conceptual diagram showing a state in which a pad figure in which a plurality of squares are overlapped is created.

FIG. 6 shows a pad figure and a solder resist opening figure, (a) is a conceptual diagram showing a circular pad figure and a solder resist opening figure, and (b) is a square pad figure and a rectangular solder resist opening figure. It is a conceptual diagram which shows.

[Explanation of symbols]

1 ... Pad figure, 2 ... Opening figure, 1a, 2a ... Line segment, 5
... 7 ... Pad figure, 5a, 6a ... Line segment, 9a-9c ... Square figure, 10 ... Pad figure, 10a, 10b ... Line segment, 2
1 ... CAD device, 24 ... Tablet as selection means,
26 ... Display as display device, C ... Clearance, P ... Pitch, W ... Width.

Claims (2)

[Claims] 1. A method for confirming the distance of a graphic displayed on the screen of a display device when designing a printed wiring board using a CAD device, wherein the graphic is selected from different graphics by operating a selection means. After confirming the pattern figures to which one line segment belongs and calculating the minimum distance between the selected two line segments based on the pattern data of each of these figures,
A method of confirming a figure distance when designing a printed wiring board, characterized in that the minimum distance is displayed on the screen of a display device. 2. A method for confirming the distance between figures displayed on the screen of a display device when designing a printed wiring board using a CAD device, wherein pattern data of different layers is constructed by operating a selecting means. The pattern figure to which one selected line segment belongs is confirmed from each figure to be calculated, and the minimum distance between the selected two line segments is calculated based on the pattern data of each figure, and then the minimum distance is calculated. A method for confirming a figure distance when designing a printed wiring board, characterized by displaying on a screen of a display device.