.net network parameters (Y-, Z-, H- and S-parameters) is implemented in Qspice. An important feature that differentiates it from other simulators is the ease of importing Touchstone .s2p files into circuit simulations.
In the SPICE community, Helmut Sennewald developed a program (s2spice.exe) to convert Touchstone .s2p files into a library containing a .subckt for .net simulation. His work can be found in https://groups.io/g/LTspice/files/z_yahoo/Tut/S-Parameter
Qspice update on 01/27/2026 There’s now support for drag and drop of a 2-port Touchstone(.s2p) file onto a schematic for frequency-domain simulation.
This represents by simply dragging and dropping a .s2p file, resulting in an embedded .subckt symbol of the .s2p data file. With just one step, everything is ready for .net simulation.
Here is a comparison of simulation results from example “S-Param-example-ADL5536.zip” in above link.
The .s2p file is not necessary for running .qsch. However, for anyone who wants to try this out without downloading the entire simulation package from the link above, the .s2p file can be useful.
ADL5536_deembed_5V_Rev0.s2p (63.5 KB)
example.ADL5536.s2p.qsch (63.5 KB)
Workflow animation
