I’d like to request support for S-parameters in Qspice, if necessary limited to AC analysis.
In the past I wrote and used a S → Y → freq tables parser to get S-parameters into LTspice, but there are issues with finding the correct DC operating point (even when it is included and correct as it is in the S-parameter files, I’m using. I have not yet tested this approach with Qspice but native support would be better.
In my case the DC point is necessary since I use non linear capacitance models connected to the S-parameter ports.
S-parameter analysis has been supported in Qspice since the January 26 update. The .net feature has been implemented and also supports dragging and dropping a .s2p file into the schematic to generate an S-parameter subcircuit model, a process that requires a third-party tool in LTspice. These are critical updates related to the .net implementation.
01/14/2026 Implemented a .net command to extract small signal network scattering parameters.
01/15/2026 Implemented Smith charts.
01/20/2026 A resistor’s AC value can now be complex.
01/25/2026 Implemented export of S-parameters in Touchstone file format.
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.