Maximum Distance to Size Ratio

This control defines the maximum spacing between vias which can be considered part of the same array. While the distance between vias is measured from the center lines of the individual vias, the control is a ratio of distance to via size. This distance cannot exceed the value of this ratio multiplied by the via size. The default setting is 6.0 and the larger the value, the more widespread the vias can be and still be grouped in the same array. Since individual via cross-sections can be of any shape, the square root of the via area is used as the via size.

For our example the size of the vias is 2.0 mm and the center to center spacing is 4.0 mm, as pictured below. This results in a Distance to Size ratio of 4.0/2.0 = 2.0 so that this array meets the via spacing criteria.