An algorithm for identifying unstable operating points using SPICE
M.M. Green, Alan N. Willson · IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems · 1995
The standard SPICE dc operating point analysis does not distinguish between stable and unstable operating points. Circuit designers can be misled when an operating point "looks" correct on the basis of dc simulation but turns out to be unobservable once the circuit is breadboarded or fabricated. The algorithm presented herein can identify a large class of unstable operating points, and it has been incorporated into the SPICE dc operating point analysis without compromising analysis speed.>