NETEX-G Topics

• 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  


Example - Extract BF3 and Neighbor Nets

We want to extract BF3 and we would also would like to deal with the effects of coupling to other nets in the package. By requesting a "neighbor net" we are telling NETEX-G to find any metal that intersects the expansion region, grab the entire net and output it. The final extraction will include the selected net and any other net who crosses into the expansion area.

Extract BF3 with neighbor nets and expansion = 0.25 mm

Extract by Node Name - I entered BF3. NETEX-G will find the net that BF3 sits on and extract that net.

Neighbors - I checked Neighbors and selected a file name BF3+neighbors.txt. This will contain the net associated with BF3 and all neighboring nets.

Expansion Distance - I entered .250 (mm). So my selected net will be swelled up by .250 mm on all sides and then all of the other nets will be examined


Two files will be generated. The file called proximity_test.txt contains all of the nets that were isolated in the design. (there were 280 separate nets in this package.) The file called BF3+neighbors.txt which was created by the extract directive

Here is an excerpt from the BF3+prox.txt file:

LIBRARY BF3+PROX_0.NTX unit:MM grid:1000000
NET Net77  C3 4240000 21260000 3  BF3 6820000 17420000 1
3806140 22123520
3806632 22117263
3808098 22111159
3810500 22105360
6191258 19088607
6192489 19104250
NET Proximity_Net0
6862454 17772668
6861690 17762960
6862613 17751227
6865361 17739784
6869865 17728911
6876014 17718876
6883658 17709926


    Line 1 gives the database units and grid resolution. Divide the coordinate integers by 1000000 to get MM.

    Line 2 is the requested net. It has an arbitray net name, Net77 since I did not enter any net labels. It also indicates that nodes BF3 and C3 are touching this net (C3 is on the bottom; you can tell by the stackup number 3.)

    Line 3 starts a conductor boundary. The 3 following the boundary indicates it is on stackup layer 3 (the bottom). A boundary is closed with the ENDEL statement.

    If a net is fully routed (i.e. it starts on the top and ends on the bottom of the package) it must have at least three boundaries.

    the proximity net however many have as few as 1 boundary and there is no real upper limit to the number of boundaries in it.

  Net77 and its proximity net.

NET77 and the various pieces of conductor that intersect it's expansion region.

Next Up: Neighbor Nets ....

Extraction Dialog:     1   |   2   |   3   |   4   |   5   |   6   |   7   |   8  


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