Netex-G web page header

• Introduction
• Applications
• User Interface
• Gerber File Requirements
• Vias from Drill Data
• Layer Stackup
• Wire Bond Data
Assigning Nets and Nodes
• From ASCII Table
• From AIF
• From IPC356
• From GBRVU

• ASCII Output
• Ansoft ANF
• Geometry Options
Proximity Effect
• What is a Proximity Net?
• What is a Neighbor Net?
• Extracting Nets
Netex Engine
• Program Flow
• Job File Syntax
• Command Line Syntax
• drl2gbr engine
• generating wire coords


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.