Maximum Size to Size Ratio

This control defines the maximum allowable difference in via size to be considered part of the same array. The default value of this ratio is 1.5 and the larger the value, the greater the difference of via size is allowed within an 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 this example, the via cross-section is a 2.0 X 2.0 μm square. The area is 4 μm2 and taking the square root, yields a via size value of 2 μm.

Since all of the vias are the same size in this array (2.0 μm) the Size to Size ratio is 1.0, so that this array meets the via size criteria.

 If you wish to limit your arrays to vias of the same size, set this control to 1.0.