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Trying to incorporate a user defined expression/function for a Resistor

Hi all,


I'm working on a simple RC circuit that contains a Voltage, Capacitor, Resistor, and 2 voltage probes before and after the resistor. I want to make a User defined expression for the Resistor value and what I did was go into the transient settings, and in the output section added a couple of constant values (L = 0.125, K =V(PR1)*100, and A = 3.5). Then I made the expression R(1) = L/(K*A). When I double clicked the resistor and changed the value a constant ohm value to the Variable R(1), it told me that R is a unsupported math function. Shown below is what the resistor looks like.

Any ideas or help?


Much Appreciated,


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Message 1 of 12

A resistor that changes its value during the simulation can be represented in parametric analysis as linearly increasing, as follows



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Message 2 of 12

Or by introducing a parameter into the analysis. The parameter can be assigned ANY change function



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...-and this is an option using a 'parameter'.
In the resistor value we write not a number, but 'R', the program will spit and swallow...

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Thanks for your feedback fango! The only problem I have now is that I don't understand Russian so I was wondering which tab or window allows me to edit the resistor parameter that was shown in the photo.

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Message 5 of 12

One of the options for changing R1
If it’s still relevant, I’ll switch to English and repeat the simulations



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Message 6 of 12

Here is an example of how a time dependent potentiometer works in time analysis



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Message 8 of 12

Hi, so I was able to get the resistance expressions to work with time and constant voltage, but I can't seem to read voltage drops using probes not sure if this is a bug. Also when I use a sinusoidal voltage component, it doesn't read well. Like if V(V1) was a sin function of voltage and I apply that as the expression for the resistance divided by 2 (V(V1)/2) it becomes a straight line instead of the sin curve. Any ideas on why that is?

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Message 9 of 12

Hi colleague! So I’m sitting, thinking, why, when we love a woman, everything turns out like this! And when they love us, something doesn’t add up, or it turns out quite the opposite...
LGBT cause! And where have all the NI-! specialists gone?


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Message 10 of 12