Pisa is a matlab toolbox for closed-loop stability analysis of electronic circuits.

Pisa can detect instabilities in the circuit and estimate the location of the unstable pole(s). To detect instabilities, pisa computes the projection of the circuit’s impedance onto a basis for unstable functions. When an instability is detected, pisa can estimate the location of the unstable poles with high accuracy.

• Works with any simulator, because only an AC analysis is needed.
• No internal access to transistor models is required.
• The projection is performed with the FFT, so pisa is very fast.
• It is designed to handle circuits with distributed elements, like transmission lines.
• Pisa’s common-denominator framework allows accurate estimation of unstable poles.
• The toolbox includes data import tools for ADS and sNp files.