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I am running pss+pnoise analysis on LDO + VCO (LDO being the power supply for the VCO). The VCO is a ring oscillator. All bondwire models are included and so are external capacitances on the LDO. I get the following warning from pnoise: "The Floquet eigenspace computed by spectre PSS analysis appears to be ill-defined. PNOISE computations may be inaccurate. Consider re-running the simulation with smaller reltol, different tstab(s), and method=gear2only. Check the circuit for unusual components." I have tried out the suggestions (smaller reltol, increased tstab, gear2only). The warning does not go away. The warning does go away if the bondwire inductances are taken out. I would however like to simulate the noise with the bondwire inductances. Any ideas on what could be going wrong here? thanks in advance, Aarathy
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