Maybe some help, Pascal:

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I got this to compile and “run” without errors, as below:

First, to fill in some unknown values:

?????????????? .params emax=10 c=5 ts=2

Made a voltage source to create and set a value for node “tptc”

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Then applying your equation to a behavioral voltage source (BV) in the F2 menu:

?????????????? V={1/(1/(emax)+0.5*(1+tanh((v(tptc)-ts)/c)))}

(This syntax didn’t work with a normal V source.)

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One set of curly braces surrounding everything that needs to be evaluated at run time.

Removing the square brackets? around “v” in v(tptc)

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The BV source put out about 902mV, if that makes any sense in your circuit…

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Dave

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