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Hello, First, Good Job on this website! It will prove to be very useful!

Issue: I created a simple RC circuit ().

When simulating this circuit using the Time Domain simulation method, if I set the "Skip Initial" option to No, the output voltage at Node 2 (V-Cap) is a flat line at the V1 voltage. If I change the "Skip Initial" setting to "No", I see the expected curve.

Am I unclear on the meaning of the Skip Initial feature, or is this a bug?

Thank you!

Ryan

Ryan, V1 is a DC voltage source, so it is assumed that its value is constatnt for all t (from t = -infinity to t = +infinity). Transient analysis starts at t=0, so the initial voltage across C1 must be equal to V1. That's why when you turn on the initial conditions calculation, the program comes up with a constatnt 1V voltage. When the initial conditions calculation is turned off, the initial (i.e. at t=0) voltage across C1 is assumed to be zero and the program calculates the response as if V1 was a unit step pulse of 1V amplitude. Hope it helps. Cheers, Ben.