GBRUnion was developed to help designers clean and convert Gerber files to contour data. It does this by performing a union operation on draws, flashes and areas. Once a layer has been unionized there are no overlapping or touching boundaries. The resulting file can be output as Gerber, DXF, GDSII or EGS Archive.

Applications

Typical Application - BGA Conductor Cleanup

At right is a snapshot of Gerber data for the top metal layer of a ball grid array. You cannot easily tell what Gerber commands (strokes and flashes) are used to create the image when it is displayed "solid".

If we change the viewer to display only centerlines we can now see that the Gerber file consists of many overlapping strokes and flashes. If you were to import this directly into a EM simulator, one would have quite a lot of cleanup to do before the data was ready for analysis.

Running this file through GBRUnion reduces the geometry to simple and clean contours. This is how a field analysis tool would like to read the data so that it can be efficiently "meshed."

Several outputs are available depending on the tool you use: DXF (Ansoft/Maxwell), EGS ( for users of Agilent's ADS/Momentum) or GDSII (AWR). There is also a version of GBRUNion integrated into CST's Microwave Studio.

Application Notes

Importing Gerber into ADS - this note describes how to use GBRUnion to import Gerber data into Agilent's ADS/Momentum layout system.

Converting a Leadframe drawn in AutoCAD into Ansoft's ANF - Flash Tutorial. (15 minutes) Takes you from cleaning the AutoCAD drawing, conversion to Gerber, running NETEX-G and examining the resulting Ansoft ANF file.

DRILL2GBR feature added to GBRVU Reads Excellon and other drill formats and converts to a Gerber RS274-X file. Useful for extracting the via information when modeling PCBs and packages.