ltspicesimulation
I want to find the settling time (i.e. the voltage at C1 not leaving a band of 1% anymore) of a step response in a circuit like this:
The step response looks like this:
As I have a more complicated case and a lot of variables I want to determine the settling time efficiently using the .meas command. The trigger would be the rising edge of V1, but how can I find the point in time, where the response won't leave my 1% band anymore? The number of oscillations is not known.
Use the SpecialFunctions/Varistor.asy component with a time-varying voltage source
I've never used it, so I cannot give more details.
After the run, if your plot window is active, there is a point available:
File -> Execute .MEAS script
From the LTSpice help:
.MEAS statements are done in post processing after the simulation is completed. This allows you to write a script of .MEAS statements and execute them on a dataset. To do this, make the waveform window the active window and execute menu command File=>Execute .MEAS Script. Another consequence of .MEAS statements being done in post processing after the simulation is that the accuracy of the .MEAS statement output is limited by the accuracy of the waveform data after compression. You may want to adjust the compression settings for more precise .MEAS statement output.
So you are correct, the data is all there and the statement is just performed on the available data set and nothing special happens during the simulation.
Best Answer
You can use this command:
Alternatively, you can concoct something like this for a more "dynamical" approach:
I commented out the
.stepcard so that the results are a bit more visible. This is just one approach. Note that this implies knowing the I/O step value(s). I suppose you can do that by simple subtraction, but you know what cases you have for that.