opamp DC gotchas PUBLIC

WHATEVER THE BUG WAS IN CL THAT CAUSED THIS PROBLEM: IT NOW SEEMS TO HAVE BEEN FIXED (140202).

Beware convergence errors in CL opamp circuits!

Three versions of the same basic circuit.

An inverting x100 DC amplifier with 0V input.

The voltage at each output should be roughly 100 times the input offset voltage (assumed to be zero for CL opamp models).

If the expressions in V1 and V2 are:

13

then a convergence warning will appear in the bottom right of the editor window.

If the expressions are replaced with:

13*(1-exp(-T/10u))

then the simulation converges realistically.

Simulate > DC > Run DC Solver

Simulate > Time Domain > Run Time-Domain Simulation

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