About Importing ECAD Databases
Board Assembly Files and Library Files
The import process requires two reference files, the board file and a library file. The board file describes the board outline, thickness, any keepin or keepout areas, and the placement positions of all the parts. The library file contains the footprint and height information for all parts referenced in the board file.
In the IDF format, the board file has an .emn extension while the library file uses the .emp extension. Proprietary formats from other vendors use their own extensions. During the import, you are prompted for the location of both these files.
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• When importing a panel assembly, specify the board file (IDF *.emn) instead of *.emp when prompted for the library file.
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Importing IDX Files
You can import an EDMD (*.idx) file to Creo Parametric. The import of an IDX file creates a new ECAD assembly. The board can have components on top or on bottom. A board outline is required and you can set holes filtering. A notification and log file is created displaying import information. Embedded holes (holes created as part of the component itself) in Xpedition are imported into Creo and behave as regular holes. Zones on a board are interpreted as additional board outlines and only one board outline is allowed.
The board outline is defined by the ECAD tool and is not modified during the import process. What appears as a straight continuous line or a smooth arc can consist of multiple discrete segments. This will become apparent when you edit the definition of the board outline or create new flexible planer walls.
Automatic or Partial Assembly on Import
When you are importing an IDF file remember the following:
• You can import the whole database, including the board, all placed components, and keepin or keepout outlines in an automated sequence that produces a completed board assembly. When you choose the automated sequence, you are prompted for any part library files or default dimensions that are required.
• Alternatively, you can import the board and parts separately and assemble them in the normal way.
When you import a design into Creo Parametric, by default the ECAD package name is used either to create a component using the XYZ data in the exchange file or to assemble board components from a common library. When a hint.map file is not used and the exchange file contains components which have a common package name, 0603 for example, and unique part numbers for different sizes, you must set the ecad_comp_naming_convention configuration option to make sure there is accurate assembly of library components or automatic component creation using XYZ information in the exchange file.
During import without a hint.map file, the application tries to find matching components in session, in the working directory, or search paths. When a matching component is found, it is assembled. When a matching component is not found, the footprint and z information contained in the import file is used to create a new part file.
Automatic Part Creation
When the parts list and placement information are read in, ECAD uses the 2D part outlines it detects to extrude each part into a 3D shape. During the import, if no defaults are specified in your config.pro file, you are prompted for a height or for a coordinate system name for the part being created. Alternatively, you can reference a library of custom-made parts that you have prepared in Creo Parametric that show more detail than a simple extrusion.
As each part is created in 3D and added to the assembly, it is saved as a separate .prt file in the working directory. The original component name, for example, SN74ALS133N, becomes the file name. One .prt file is created for each reference designator. All reference designators appear on the Model Tree.
Custom Part Substitution
As an alternative to letting Creo Parametric create the parts automatically, you can create a library of more accurately-shaped custom parts and reference it when you import the PCB. You use an ASCII map file named ecad_hint.map to reference the custom parts as substitutes for the automatically created ones.
Automatic Layer Assignment
When the preferences option, ecad_comp_layer_map, is set to yes, the import routine creates a new layer for each component name and places each newly created reference designator on the appropriate layer.
If you are referencing an ecad_hint.map file, you can add lines to the file to direct layer creation and part-layer assignment.
Additional Supported Objects for IDF Import-Export
In addition to the board and electrical components, ECAD also imports and exports the following objects in accordance with the IDF 3.0 specification:
• Panel Outline—The manufacturing step-and-repeat panel and boards mounted on it. The panel outline is described in an optional separate panel file which can reference one or more board assemblies described in separate files. Any component placed on the panel itself is referenced in a library file.
• Other Outline—Extruded shapes of nonelectrical parts that would not have a reference designator, such as a heat sink.
• Holes—Drilled holes and lightweight holes.
• Keepin and Keepout areas—Separate outlines can show where to place or prohibit parts, routing, or vias.
For complete information on the IDF import file conventions, see the Intermediate Format Specification Version 3.0.
Supported Objects for IDX Import-Export
In addition to the board and electrical components, ECAD also imports and exports the following objects in accordance with the IDX 3.0 specification:
• Board—The board is a separate part file, in an ECAD assembly.
• Holes—Drilled holes and lightweight holes.
• Areas—Separate outlines can show where to place or prohibit parts, routing, vias, or user defined areas.
• Bends—Supported for export.
Notes, panel, and other outline are not supported by IDX.