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Variants Integration in P-CAD 2004.

Product requirements may warrant the need to produce a variety of similar Printed Circuit Boards that all differ slightly from an underlying base design. They may vary from the original with respect to:
· the number of original design components it contains. (e.g. standard and deluxe versions of a commercial product) and/or
· the attributes of those components. (e.g. resistors with different values and tolerances).

The variants feature allows you to create variations of your design without having to create explicit PCB document designs. The variant information is stored with the ‘Parent’ PCB design and is used when generating print-outs, reports and ECO’s. This has several advantages. When a change is made to the base design, all the variants are updated automatically. This eliminates the time-consuming and error-prone task of manually replicating changes in multiple design databases. Another advantage is the ability to report and compare the variants to each other and to the base design. All documentation, including bills of material (BOMs), reports and schematics, are derived from a single, controlled source.

Lets take a look at defining board variants…

Follow this example...
· File >> Open Digdemo.pcb (this file can be found in the P-CAD 2004 Demo folder).
· Select the Tools >> Variants command.
· Firstly we have options to Add a New Variant or Rename / Delete an existing one.
· Create two variants, perhaps one for a cheaper design and another for and faster design.
· Enter a name and a description for the cheaper design variant and click New. The variant will appear in the Variants list. 
· Remove components from the Included Components list. Perhaps could try removing by attribute.
· Now do the same again for the faster design variant. 

Now lets view the variant reports.... 

· In the Variants dialog, click Reports. The Variant report along with the Attributes, Bill of Materials, Component Locations, Glue Dot Locations, Pick and Place Locations and Statistics have the option to produce reports for variants under the Customise tab. Go to File >> Print >> Miscellaneous… to see the option applies to printing as well.

Variant definitions can be passed to the schematic through the use of appropriately recorded ECOs. Conversely, any changes to variants made on the schematic side can be brought back to the PCB through the import of relevant ECOs, recorded in the schematic. This allows for the synchronization of variant information between the schematic and PCB.