Ken Kundert
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You're settings look okay to me at first glance. If the circuit is not converging it is generally because the circuit is either not close enough to periodic steady-state when the tstab interval ends, or the circuit simply does not have a periodic steady-state solution. To test these, rerun the circuit in transient analysis with strobing turned on and the strobe interval set exactly equal to the period of the fundamental frequency (generally the input frequency). Then examine all the waveforms in the circuit. Every signal should be close to its equilibrium value and there should be no ripple. If the signals are not close to their equilibrium points, set tstab to a larger value. If there is ripple of any kind, then either you have the wrong the fundamental frequency or your circuit does not have a periodic steady-state solution. If the circuit does not have a periodic steady-state solution, you cannot use RF analyses (shooting methods or harmonic balance). This generally occurs when the circuit is unstable (has a parasitic oscillation). Once you determine a time when the signals reach their equilibrium values, use this time as tstab in the PSS analysis. Once you determine a fundamental frequency that results in no ripple, use this as the "beat frequency" for the PSS analysis.
-Ken
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