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MinWidth Rule

Syntax: MinWidth [EdgeArgs] width_in_microns [Diagonal alt_width] [string]

For the parts of each edge of the source that are not coincident or overlapping with source-compatible figures, a rectangle extending normally from the edge into the source figure by the given dimension is constructed. The test fails if this constructed rectangle is not completely covered by source-compatible figures. Note that the angle formed by two adjacent edges of a figure measured inside of the figure must be 90 degrees or larger, i.e., this rule prevents acute angles in polygons. Figure 15.8 illustrates the test performed under this keyword, for no Region.

If the Diagonal clause is given and the alt_width is positive, the alt_width will be used when the edge being tested is nonorthogonal.

The MinWidth test also fails if the length of a line defined by the overlap points of two mutually overlapping corners of a source figure and another compatible figure is less than the given dimension, including the condition where corners of the two figures touch but the intersection area is zero.

When importing Virtuoso technology data, the minWidth constraint maps directly to this rule.

The Diagonal clause is set by minDiagonalWidth constraint when importing virtuoso technology data. This may have its own reference string. To keep this distinguishable, the string can actually be two double-quoted strings, e.g., the form is

"# rule description" "minDiagonalWidth string"

This guarantees that the original reference strings are regenerated when the !dumpcds command is used to generate a Virtuoso technology file. If a component string doesn't exist, one can use "" (two double-quote marks) as a placeholder. Strings to the right that don't exist can be skipped entirely.

Figure 15.8: The MinWidth test. The edge-to-edge spacing across a region on the present layer must not be less than the given dimension.
\begin{figure}
\vspace{1.5ex}
\begin{center}
\epsfbox{images/minwidth.eps}
\end{center}\end{figure}


next up previous contents index
Next: MinSpace Rule Up: Edge Rules Previous: MaxWidth Rule   Contents   Index
Stephen R. Whiteley 2019-11-22