The Construct Pads (Auto.) action converts drawn pads to Genesis pads. The action implements a heuristic algorithm to identify groups of features that are most likely to form pads, and utilizes a sophisticated recognition algorithm to substitute the most appropriate Genesis pad(s) for a specific group of features.
The action recognizes the following Genesis standard symbols:
* Rectangle (Regular,
Round-cornered, Chamfered)
Thermals of all types are supported, as long as they have only 3, 4, or 5 spokes.
*
Octagon, hexagon, butterfly, triangle, half oval, and ellipse are not
supported. Rectangular thermals are not supported.
The action recognizes rotated rectangular and oval pads. They are substituted according to the Genesis naming convention, where a pad named sym_AAA.A means that sym = name of the standard symbol and AAA.A = angle of rotation.
As of version 8.2, the action runs on inner layers, and looks for pads when it is run on an inner layer. The action can run on an inner, positive, signal or mixed layer. The reference layer is the drill layer(s) which pierces the layer being examined (similar to the behavior of outer layers).
*
The action must have a large enough drill_margin for this search to occur.
All groups (of features) not matched with standard or rotated standard symbols are substituted by special symbols named according to the Genesis naming rules. Such symbols are named construct, construct +1 , etc. For more details about Genesis symbols and naming conventions see Doc.0202 ODB++, Chapter 9. Symbol Definition.
are allowed as part of the drawn pad content. Text features are ignored. Special pads consisting of more then one feature should be broken before action, using the Edit/Reshape/Break function in the Graphic Editor.
All features with the attributes .teardrop or .nomenclature are excluded from processing.
*
Defining features with the .nomenclature attribute
may help prevent creation of illegal constructs.
The action may be run on all features, or only on selected features.
The action may be run in one of three modes:
There are no restrictions on non-standard pad geometry. Pads of very complex geometry may be created, if they are well defined. Below is an example of two complex construct pads created by the action.
The action may be used with or without a reference layer. Without a reference layer, the action locates groups of features likely to be drawn pads according to the topology of the working layer only. This mode may be useful when used together with the Apply to selected option.
In reference mode, the reference layer passes through internal contourization, and groups in the working layer are located according to the islands created in the reference layer. (The reference layer is not changed by this action.)
*
Preliminary pad substitution in a reference layer is not
necessary, but may make the work easier.
In reference mode, depending on the
type of working layer, the action may substitute pads or thermals.
For pad detection: the positive outer signal/mixed layer is a working layer,
and the solder mask layer is a reference layer.
For thermal detection: the negative power/ground/mixed layer is a working
layer, and the drill layer is a reference layer. The relationships between
working layers, reference layers, and the types of pads that action substitutes
are described in the table below.
*
Thermals may be substituted only in Auto Ref (erence) mode.
Sometimes the solder mask clearance used as a reference is included in the drawn pad. (Such clearances are called gaskets). For thermal recognition, the drill used as a reference is always included in the drawn thermal pad. In such cases, you must set the margin value manually in order to increase the searching distance. The searching distance is calculated, for pad recognition, as the clearance limit box increased by the given margin value. For thermal recognition, searching distance is calculated as the size of the round drill increased by the given margin value. Be careful to use correct settings for the margin values. A too-large margin value may cause inclusion of non-relevant features and thus create illegal construct pads.
In some cases, the action fails to construct pads automatically. Locations where pads were suspected but were not created are reported in the Special pads category. You may substitute problematic pads manually by using this action in Apply to Selected mode, by using the DFM action Construct Pads (Ref.), or by using a function in the Graphic Editor, such as Substitute or Contour to Pad.
*
IMPORTANT
Construct
pads starting with the string: ` construct, ` construct+1, etc. are automatically set with .out_break only when the system attribute dml_auto_set_out_break is set to Yes (see Doc.0203, System
Management). This forces the Construct pads to be broken into it's primitives
in the output translation stage, regardless of any other output parameters that
are set (such as break_symbols ). Standard symbol pads
are not affected.
Displays the names and counts of each pad that was created.
The total number of constructed pads in all layers processed. |