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Applications
NETEX-G is useful since it reads one of the most standard file formats in the
PCB and packaging industry - Gerber. Even when the original design data is lost
or unreadable (remember legacy systems?) the Gerber data remains.
Gerber data represents exactly how the board was built -- design
software has been known to output Gerber different that the designer's intent.
There are three applications that NETEX-G has been used for:
- Extraction of parasitics from the 3D structure of the circuit. Because packages
and boards consist of many layers of tightly sandwiched circuitry, one must take into
account conductors and dielectrics in three dimensions in order to accurately model the
parasitic effects. Netex-G doesn't do the modeling but it does help in getting the
3D data into the simulation tools.
- Comparison of design intent to actual substrate connections. Designers have found,
much to their chagrin, that the board they have carefully designed does not always come
back correct. Problems have been traced to the way that some design tools produce the
Gerber data for the artwork -- there seems to be the opportunity, particularily for
ground planes, to inadvertantly short vias to ground. Given the dense, complex designs it
is not reasonable to do a manual inspection to find such shorts.
Netex-G can reverse extract the net connections and compare them to the desired connections;
detecting any unexpected opens or shorts.
- Thermal Modeling. Devices are running hotter and the packages must transfer more and
more heat to prevent thermal runaway. If the device is sitting on a "sandwich" of insulators
and metal patterns one requires finite element analysis tools to accurately model the
heat flow. NETEX-G can convert the Gerber data into polygons that can be cleanly input into
thermal modeling tools.
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