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Hi,
The terminated lossless transmission line shows overshoot at each rising/falling signal edge (see example file).
With previous software releases (< 26.0.0) the same circuit is functioning well.
The lossy transmission line (LTRA with R=0) can be used as work around.
Hi twopif ,
Clearly, you found one solution. The fact that there is only one data point in the overshoot suggests a time step problem, which you figured out. That said, you can also get rid of the overshoot by getting rid of the discontinuity built into an unrealistic pulse. Turn on Smooth half-sine transitions in the V source helper dialog:
That still produces a small overshoot, which is eliminated by using the 70ps time step.
I see that there is a little rise time in the longer time step. Here with 70ps:
mike
Hi twopif ,
Clearly, you found one solution. The fact that there is only one data point in the overshoot suggests a time step problem, which you figured out. That said, you can also get rid of the overshoot by getting rid of the discontinuity built into an unrealistic pulse. Turn on Smooth half-sine transitions in the V source helper dialog:
That still produces a small overshoot, which is eliminated by using the 70ps time step.
I see that there is a little rise time in the longer time step. Here with 70ps:
mike
