JPH04167183A - Wiring processor for printed wiring board - Google Patents

Abstract

PURPOSE:To obtain a wiring route to satisfy branch length by wiring a source pin and a farthest terminal load pin so as to pass a contact, and connecting an unconnected pin to the contact. CONSTITUTION:The minimum rectangle N including all the pins is set, and the center point M of the rectangle is found, and a virtual circle Ci setting designated branch length r' for the pin Li other than the source pin and the farthest terminal pin as a radius is set, and the contact with a tangent line in parallel with X and Y axes is found. The contact nearest to the center point M of the minimum rectangle M including all the pins is selected from the contacts, thence, a selected contact is wired so as to pass between the source pin and the farthest terminal load pin. Then, the unconnected pin is connected to the selected contact. Thereby, it is possible to obtain the wiring route which satisfies designated branch length in short length.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wiring processing device for a printed wiring board (hereinafter referred to as PWB).

[Conventional technology]

Conventional wiring processing equipment of this kind selects pins to be connected and stretches horizontal and vertical line segments randomly over the wiring area from each of the starting and destination pins. The method used was to find the wiring route from the path when the two intersect.

[Problem to be solved by the invention]

In the conventional PWB wiring processing device described above, the pins to be connected are selected appropriately, or the wiring route is simply determined using random horizontal and vertical components, so when branch wiring is allowed, the specified branch There is a problem in that it is not possible to find a wiring route that satisfies the length.

[Means to solve the problem]

The PWH wiring processing device of the present invention has a means for setting a minimum rectangle that covers all pins and finding the center point when wiring signal lines with three or more terminals in printed wiring board wiring design, and a source pin and the farthest end. For pins other than load pins, set a virtual circle with a specified branch length as the radius, and find the points of contact with tangents parallel to the X and Y axes. means for determining the contact point closest to the center point, one for each pin other than the source pin and the farthest end load pin; means for wiring the source pin and the farthest end load pin so as to pass through the contacts; It is characterized by having means for connecting the contacts.

〔Example〕

Next, the present invention will be explained using the drawings.

FIG. 1 is a flow chart of the present invention.

In process 1, as shown in FIG. 2, a minimum rectangle B including all pins is set and its center point M is determined. In process 2, i=0, and in process 3, i is incremented by +1.

In process 4, pins L excluding the source pin and the farthest load pin
A circle Ci is set with i as the center and the specified branch length r as the radius. Next, in process 5, as shown in FIG. 3, four points of contact Dj with tangents parallel to the X and Y axes are found for the circle Ci.

In process 6, as shown in FIG.
Select from J. Let this be Ei. Processing 3 to processing 6 are then repeated until i≧total number of pins −2 in processing 7.

Next, in process 8, as shown in FIG. 5, wiring is made from the source pin to the farthest load pin so as to pass through the contact point Ei determined in process 6. In process 9, i=0, and in process 10, i
Increment by +1. In process 11, the unconnected pin and the contact point Ei obtained in process 6 are connected.

Processes 10 and 11 are repeated until i≧total number of pins - 2 in process 12 to complete wiring of all pins. FIG. 6 is an example of a wiring pattern obtained by this process.

〔Effect of the invention〕

As explained above, the present invention sets a minimum rectangle that includes all pins, finds its center point, and sets a virtual circle whose radius is the specified branch length for pins other than the source pin and the farthest load pin. Find the point of contact with the tangent line parallel to the axis/Y axis. The contact closest to the center point of the minimum rectangle containing all pins is selected from among the contacts. 6. Next, wire is routed between the source pin and the farthest end load pin so as to pass through the previously selected contact. By using a means of connecting an unconnected pin to a previously selected contact point, it is possible to relatively easily obtain a wiring route that satisfies the specified branch length with a short line length.

[Brief explanation of the drawing]

Fig. 1 is a flowchart of the present invention, Fig. 2 is a diagram showing an example of the minimum rectangle B including all pins and its center point M, and Fig. 3 is a circle centered on the pin Li with a specified branch length r as a radius. A diagram showing an example of the contact point Dj between Ci and a tangent line parallel to the X-axis and Y-axis, FIG. 4 is a diagram showing an example of the contact point Ei closest to the center point M of the minimum rectangle B, and FIG. A diagram showing an example of wiring between the farthest end load pins so as to pass through the contact point Ei, and FIG. 6 is a diagram showing an example of the wiring pattern obtained by this process.

Claims (1)

[Scope of Claims] When wiring signal lines with three or more terminals in printed wiring board wiring design, means for setting a minimum rectangle including all pins and finding the center point thereof, and pins other than the source pin and the farthest end load pin. Set a virtual circle with radius equal to the specified branch length, and find the point of contact with the tangent line parallel to the A means for finding one close contact for each pin other than the source pin and the farthest load pin, a means for wiring the source pin and the farthest load pin to pass through the contact, and a means for connecting the unconnected pin to the contact. A wiring processing device characterized by having a means.