Running netexi on Linux&Solaris

This page describes the basic procedure for running the netexi Windows (the netlist extractor user interface) on a GDSII file. The product allows you to select the GDSII file, select the technology file which has the stackup information, and the configuration file which contain information on the type of extraction (by net name or location) etc.

From the main menu, click on the Browse to select the GDSII file you want to process. For our example, pick demo.gds from the examples directory.
The top structure name will appear automatically. You can change that if you want to process a different cell/structure. For our example, TOP is the top cell so we will use it.
From the main menu, click on the Browse to select the Technology file you want to use. For our example, pick tlib.lib from the examples directory.
The technology file editor allows you to define the layer stackup. In this example, the stackup is pre-defined. For your GDSII file, you will probably need to create a new technology file and create your own stack-up. Once created, the file can be saved and used again.
We explain in detail all the different parameters of the tech file in the NETEX web page.
Technology file page

From the main menu, click on the Browse to select the configuration file you want to use. For our example, pick bylabel.cfg to see how to extract nets by specifying the net names you are interested in (in this case you must have a layer with the net information defined as text in the GDSII file).
For our example, we will choose bylabel.cfg - click on the Extraction menu to see the output file name that netexi will generate. This will be the file with the extracted nets. You can also click on the Edit button next to it to look at the net names we are looking for. The nets that match the criteria will get extracted to the output file.
In our example, the output file name will be by_label.gds and the labels/nets we are looking for are l2clk.* (any net that starts with l2clk).
We explain in detail all the different parameters of the configuration file in the NETEX web page.
Configuration file page

From the main menu, click on the output format menu to select the type of output you want.
We support output file in GDSII, but we can also create an output file for certain simulation tools like Ansoft (ANF), Optimal (XFL), and OEA (ASCII).
For our example, we will select the XFL output. Netexi will create a GDSII file with all the nets as well as the XFL file for Optimal with the specific nets we requested, l2clk.*. We will then view the output with our Qckvu GDSII viewer and with Optimal's OModel software.
We explain in detail all the different output formats on this page.
Output format.

From the main menu, click on the compute nets to start netexi.
The program will start running and after a few seconds it will finish and write the output file to disk.
At this point you can click on View output to view the GDSII file (bylabel.gds).
Note that the program also created a complete file called demo_neall.gds which contains all the nets in the input file.
This file contains the same data (polygons/layers) as the input file, but it is now organized by nets and the original hierarchy is gone.

Once in Qckvu, you may click on the structure menu (you can access it from the main tool bar or through the Setting pull down menu), and review the nets in your file. Each net was translated to a cell in the GDSII file. You can preview with Qckvu the full GDSII file with all nets or preview each net separately by selecting the net name and hitting the Apply button.