I have problem on my op amp modelling, i want to anlysis op amp inverting circuit but the simulation from my circuit not inverting
Hi Nur, could you please add label on the wire? It can help us where your signal waveform was taken.
-Mac
Thank you, this is very helpful, but I still have a question. How do I use a potentiometer in Qspice? I want to replace R1 with a potentiometer
You’re welcome. You can use a behavioral resistor and variate the R values.
what is the parameter of V(rf)? how if using potentiometer 1k?
V(rf) is a variable R value, which you can set by changing the parameter of V4. I think you can develop the potensiometer model that you want with this concept.
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Thank you the solution, this is very helpful.
Potentiometer normally with 3-terminal, I have two symbol (.subckt) for potentiometer in my Github below, you can download the Potentiometer.qsym and Potentiometer-VCTRL.qsym. An example is shown below.
Qspice/Symbols/analog at main · KSKelvin-Github/Qspice
Parent.Potentiometer.qsch (3.9 KB)
What @macsky shown you is behavioral resistor. It can be used as variable resistor and its resistance can be described by a function. It can be constructed with B-source (press B 3 times) or Resistor (R-device) with R=<function/formula>
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What a nice explanation Kelvin, thank you.
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Thank you for the explanation Kelvin, very helpful.