JPS6161487A - Pattern wiring system of printed board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Utilization of the Invention] The present invention relates to a pattern wiring method for printed circuit boards, and in particular, a conductor pattern that facilitates automatic wiring through high-density mounting and allows functional testing and repair from the back side of the board. Regarding wiring method.

[Background of the invention]

In recent years, printed circuit boards have a lead wire pitch of 5Q mi.
Parts are used for the imposition of j, but in conventional automatic wiring design (hereinafter referred to as DA), processing of mixed pattern running paths (channels) in the grid (for example, when one and two channels are mixed) ) is difficult, and in-circuit testing of parts is also not possible with the above-mentioned imposition.

FIG. 2 is a plan view of a conventional printed circuit board pattern wiring.

In FIG. 2, 1 is the X and Y grids on the printed circuit board, 2 is a steel plated through hole and pad for inserting electronic components, 3 is a square pad for mounting surface-mounted components and soldering, and the heather is a conductor pattern wiring.

In the DA wiring in conventional machines, conductor pattern running paths running in parallel between orthogonal X and Y grids can only be formed at predetermined positions and in a predetermined number. The reason for this is that first, the lead wire spacing is 1.27mm (5Qml), and the width of the square pad δ must be approximately a certain degree (for example, about 0.7mm).

On the other hand, in order to achieve high-density wiring, it is necessary to set as many conductor wiring pattern running paths as possible between the X and Y grids. However, according to the traditional printed circuit board manufacturing method,
The number of conductor pattern wiring between square pads 30 with lead pitch of 1.27 m is 1, and
, the number of conductor pattern wires between the Y grids is approximately two.

By the way, the search for a DA wiring pattern route by a machine is performed using an algorithm such as a line segment search method or a maze method only on conductor pattern wiring paths set in advance between grids.

In this case, the conductor pattern wiring route set in advance cannot be changed each time.

In Figure 2, between the X and Y grids 1.275m,
It shows a row in which two (4a, 4b) conductor pattern wiring running paths are set. However, in FIG. 2, for example, when the vehicle travels on the conductor pattern travel path 4b and passes to the right from the corner pad 3, it collides with the corner pad 3 and cannot run. Therefore, it is conceivable to move from the running path 4b to the channel 41 and run, but in this case, even if you move to the channel 4a, you will still collide with another corner pad 3, so you will not be able to run. I can't. therefore,
In order to solve this problem, it is possible to set up 3, 5 or more channels between 1.27 grids on the Manufacturing yield decreases, leading to higher costs. Further, signal crosstalk between wirings occurs, reducing practicality.

On the other hand, if only one conductor pattern running path is set in the center of the grid, it can pass between the square pads 30, but there is a drawback that the mounting wiring density is reduced.

In addition, the most advanced method for testing the functionality of printed circuit boards after mounting surface-mounted electronic components is to press a probe from the back side of the printed circuit board (this is called the in-circuit test method). However, it is not suitable for functional inspection of a printed circuit board equipped with a soldering layer pad 3 and mounted with a surface-mounted electronic component. Further, since such a board does not have the through hole 2, it has the disadvantage that it is difficult to repair the board after the fact.

[Purpose of the invention]

The purpose of the present invention is to improve such conventional drawbacks, and to utilize the printed circuit board manufacturing technology and circuit board function testing equipment as they are without changing them, and to realize high-density wiring of printed circuit boards on which surface-mounted electronic components are mounted. The purpose of the present invention is to provide a printed circuit board pattern wiring method that enables easy repair and testing after the fact.

[Summary of the invention]

In order to achieve the above object, the printed circuit board pattern wiring method according to the present invention provides several holes for component insertion and front and back connections and pads for mounting solder material on surface-mounted electronic components on orthogonal X and Y grids. In addition, in the printed circuit board on which a conductor pattern running path is provided on the X and Y grids or between the grids, a conductive pattern running path is placed in advance on the non-grid between the F pads, parallel to the pad, and near both ends of the pad to the pattern running path. The present invention is characterized in that a conductor pattern outside the running path is provided in a bent shape, and a copper-plated hole is provided at a position from the corner pad to the lead wire on the grid.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to FIG.

In Fig. 1, 5 and 15 are conductor pattern wiring patterns outside the running path, 6 is a conductor pattern wiring for extraction, 7 is a copper plating through hole for inspection, and a pad.Other symbols are the same as in Fig. 2. show.

In Fig. 1, the new points are (1) By passing the pattern 5°15 outside the conductor pattern running path, which was previously installed as if it were a component, on the printed circuit board. To enable wiring without reducing packaging density by DA even if there is an obstacle such as a component mounting pad on a conductor pattern wiring running path running in parallel between orthogonal X and Y grids. and (l
I) By providing the through hole 7 in the surface-mounted electronic component mounting square pad 5, the function can be inspected from the back side of the printed circuit board, and repairs can also be performed.

The above (1) will be described in more detail.

In DA, the orthogonal X, Y grid 10 intervals are 1.
27fi (50 mil), and copper-plated insertion through-holes 2 for mounting electronic components and square pads 3 for mounting soldering surface-mounted electronic components are arranged on the grid of the printed circuit board. A conductor pattern wiring line 4 runs on the X and Y grids, and a first conductor pattern running path 4 also runs between the grids.
a, a second conductor pattern running path 4b is provided.

Further, the square pad 3 is provided on the X and Y grids 1, and conductor pattern wirings 5 and 15 outside the pattern running path corresponding to the conductor pattern wiring width are provided in advance at the centers of the grids. In addition, the starting point A and the ending point B of the conductor pattern wiring 5°15 outside the running path are 's2
It is bent and extended above the conductor pattern wiring running path 4b. In order to create the conductor pattern wiring 5, 15 outside the running path, in the same way as the square pad 3, the light point narrowed down by the aperture is automatically cast onto the film photosensitive film, and the original film is exposed. Draw a diagram.

A so-called automatic photo-drafting device is used to expose and form the pad 2 surrounding the electronic component insertion through hole and the square pad 3 for the surface-mounted electronic component mounting solder material at predetermined positions. Next, a conductor pattern 5.15 outside the conductor pattern wiring running path is formed in the same manner as the pads 2 and 3 using an eccentric aperture having the origin at point A or point B.

For example, in the case of a conductor pattern wiring that needs to run on the second running path 4'b and pass to the right of the surface-mounted electronic component mounting square pad 3 according to the automatic route search, if the running path 4'
When reaching point A through B, the control is automatically transferred to point B at the same time as reaching point A via the pre-prepared conductor pattern 5 outside the pattern traveling path, and the pattern travels to the right from point B. The route search continues on Road 4b.

In this way, the two-pattern conductor pattern 5 outside the running path is prepared in advance on the running path 4a, in the same way as the other pads 2, 3, etc.
By providing it as a component outside of 4b, it is possible to realize wiring outside the initially set pattern running path with the DA. That is, X.

Even number of pattern running paths 4” between 10 Y grids
Even if 4b is set, it is possible to use an odd number of patterns 5 and 15 outside the pattern running paths, which is smaller than the number of pattern running paths, between the wide pads 30, so that maximum high-density wiring can be efficiently realized. .

For example, with an X, Y grid 1 with a spacing of 1.27 mm, place one conductor pattern wiring with a width of 0.2 mm between the 0.7 mm width of the parallel plate 1゛3 for mounting surface-mounted parts on the grid. Through,
Two conductor pattern wirings can be run between the other grids.

Further, when the preset pattern running path M conductor pattern 15 is not used, this pattern 15 is automatically erased so that no unnecessary pattern remains. As a result, manufacturing defects such as solder bridges can be minimized without lowering the printed circuit board manufacturing yield unnecessarily, and when soldering electronic components.

Next, regarding (11) above, the conductor pattern wiring 6 for drawing out from the square pad 3 provided on the orthogonal X and Y grids 1, and the through hole for front and back connection wear inspection provided at the tip of the wiring 6. 7 in pairs. The through hole 7 has a smaller size than the electronic component matchmaker hole 2, is copper plated, and is used for through connection between the front and back sides and for functional inspection from the IA side.

That is, in the conventional wiring method shown in FIG. 2, it is impossible to perform an operational function test from the back side of the printed circuit board after surface-mounted electronic components are mounted, whereas in this embodiment shown in FIG. Along with the solder pad 3 for mounting surface-mounted electronic components, a lead-out conductor pattern wiring 6 and a copper plating through hole 7 for inspection are provided, so that after mounting surface-mounted electronic components, a test probe can be inserted into the inspection hole 7 from the back side of the printed circuit board. By pressing the , it is possible to perform operational function confirmation tests without changing existing equipment. Moreover, this inspection hole 7 is
Because the dimensions are smaller than other pot-plated through holes 2 for inserting electronic components (specifically, the pad diameter is about 0.5-==1)
However, the number of pattern running paths is not reduced, and high-density mounting wiring is not affected in any way.

〔Effect of the invention〕

As explained above, according to the present invention, the conductor pattern outside the pattern running path is provided in advance in the same way as other pads, etc., and the tip of the conductor pattern pulled out from the surface-mounted component mounting pad is used for both front and back connection and inspection. The provision of through holes makes it possible to perform high-density wiring through automatic wiring of printed circuit boards that carry surface-mounted electronic components without changing printed circuit board manufacturing technology or circuit board function inspection equipment. Functional testing becomes possible.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a printed circuit board showing an embodiment of the present invention;
FIG. 2 is a plan view of a printed circuit board according to the prior art. 1: X, Y grid, 2: [Copper-plated through hole for inserting child components, pad, 3 = square pad for solder material mounting surface-mounted electronic components, 4 & + 4 b ” conductor pattern wiring, 5 = conductor pattern wiring running Off-road pattern, 6: Conductor pattern wiring for drawer, 7: Steel plated through hole for inspection, pad.

Claims (1)

[Claims] (1) Provide multiple component insertion and connection holes and solder pads for mounting surface-mounted electronic components on the orthogonal X and Y grids, and provide conductor pattern running paths on the X and Y grids or between the grids. On the installed printed circuit board,
A conductor pattern outside the travel path is provided in advance on the non-grid between the pads, parallel to the pad, and bent to the pattern travel path near both ends of the pad, and the conductor pattern outside the travel path is detected by route searching in automatic wiring design. When the contact point of the pattern is reached, the control is transferred to the contact point at the other end of the conductor pattern outside the traveling path, and the route search is continued. Further, a pattern wiring method for a printed circuit board, characterized in that copper-plated holes are provided at positions from the pads to the lead lines on the grid.