The Rules Guide Overview
This rules guide provides information for core checks within the OrCAD X PCB DesignTrue DFM tools. Note that there are two tiers to
the DFM tools, Core and Extended. Core rules are provided as a set of default checks within the Allegro X and OrCAD X products. DFM
Extended rules require a higher tier license available within Allegro X.
General Overview
Rule values for all checks are entered as DFF Constraint Set and DFA Constraint set.
The DFF Constraint Set worksheet is where the values for the checks are entered, the type of structure the rule is to be applied
to along with a constraint name. The Design Worksheet is the location for associating the DFF Constraint Sets to the different
layer structures of the design. Each will be explored in this guide.
Both the DFF Constraint Set and Design Worksheets are broken into five (5) categories, each category is focused on a specific
series of rules. The categories are:
Outline – The outline category pertains to the PCB edge profile defined on the BOARD GEOMETRY/DESIGN_OUTLINE and
BOARD GEOMETRY/CUTOUT subclasses. The shape elements on these classes are the focus of the checks. In general, any
copper (signal and non-signal) geometry to outline and cutout, cutout to cutout, cutout to outline clearance rules are defined.
MASK – The checks in this category identify narrow areas of mask, (slivers) and small islands of mask material that may not be
of enough mask material to properly adhere to the board surface.
Annular Ring – The annular ring rules for copper pad sizes to holes, anti-pad to hole, mask to pad and missing mask checks
values are defined in this category.
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OrCAD X DesignTrue DFM Rules Guide
