Hi Richard,
?
Aside from the form Helmut gave you, you can set any resistor to as many changes as you need. The format, which is entered in the resistance window in place of a single value is :
???
???? R=table(time,0,res1,time1a,res1,time1b,res2.....,last res)
?
Example : R=table(time,0,10K,3m,10K,3.00001m,100K,6m,100K,6.00001m,1)
?
This starts with the resistance value at 10K until 3mS after start, then steps to 100K until 6mS and then to 1 ohm for the rest of the run. The run duration sets the max time end point. Careful to place comma's between each entry, and no spaces.
?
If you want a slope change instead of a step, for example a changing value of 100 ohms to 10 ohms over a 10mS time and back to 100 ohms over the next 10mS,?the form would be:
?
???? R=table(time,0,100,10m,10,20m,100)
?
Lastly, always check your entries for pairs. There must be a time/value pair for each entry. This listing approach is invaluable for all sorts of applications which require either a slope or step change such as load testing etc.
?
- Cordially - RC
?
________________________________
From: Richard Norman <rnorman3@...>
To: "ltspice@..." <ltspice@...>
Sent: Sunday, April 14, 2013 2:30 AM
Subject: [LTspice] Step a resistor over time
?
Hi All, is it possible to step a resistor over time? Right now if I use the step command like this:
.step param R 100 1000 100
.tran 0 1ms 0 1
I
end up with a bunch of parallel horizontal lines. What I want is a
bunch of points (maybe even connected) over time. So in other words,
over the 1ms, I want the resistance to step from 100 to 1000. Is it
possible?
Thanks!
Richard
[Non-text portions of this message have been removed]
[Non-text portions of this message have been removed]
