Chris,
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FYI - Your simulation runs OK after changing to the Alternate Solver.
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Control Panel (Settings) > SPICE tab > Solver: change to Alternate.
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When done using the Alternate solver, you might want to change it back to the Normal solver.? Newer versions (24.1.*) of LTspice now have a way to specify which solver to use, but older versions need to be manually changed back to Normal if that is what you normally want.
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Your circuit has much trouble simulating.
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The error log reports three instances of "Questionable use of curly braces" and three (apparently false) Errors, which are probably caused by T.I.'s LM317 SPICE model.? In my experience, those warnings and errors seem to be harmless and do not seem to affect the outcome.? They can be "fixed", if desired, so that those messages do not show up - but it's probably not necessary.
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Then the simulation has great difficulty finding the initial (DC) operating point.? Direct Newton Iteration fails.? GMIN Stepping fails.? Source Stepping fails.? Pseudo-Tran might have succeeded, but I can't be sure.
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Once past that, the transient simulation has considerable difficulty when using the Normal Solver, but only with the Normal Solver.? The .log file is full of Heightened DefCon warnings, and some of the voltages are "funny" and probably wrong.
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My guess is that something in the circuit is oscillating at very high frequency, causing considerable slowness.? Lower frequency oscillations are visible at some nodes, maybe a consequence of a >UHF oscillation.
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I can't make conclusions, but one possibility is that something in this simulation needs the extra few digits of precision of the Alternate Solver.? And maybe there's a bad model.? Since it is the circuit with the ADA8084-2 that has trouble, that one is suspect, but that's all I can say so far.
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Andy
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