RTSWITCH example

[electony]

hello, it`s possible some example for the function of RTSWITCH modeling primitive.?
thank you.

[Ettore]

RTSWITCH is substantially a variable resistor where its value is represented by a STATE number.
It gets no practical use outside an ACTIVE models; for example it is largely used in rotary switches active models.

However I attach a project file with a couple of examples:
a) The SW1 changes its internal resistor value based to given STATE value. Try STATE=0, 1, 2 and 3 (STATE is in the *DEFINE block) and the current probe value will change accordingly.
b) The 2nd example with SW2 to SW5 represents the internal model of SW-ROT4 (four position rotary switch). As you change the STATE value a lamp lights up accordingly.

[electony]

OK, and is there any way to make variable "state" time dependent?
thank you.

[Ettore]

No. STATE variable is simply a number requiring user's interaction.
Only voltages and current are time dependent in SPICE. If you need a time dependent variable resistor then you must use the Linear Voltage Controlled Resistor (VCR).
Pick it from "Modelling Primitives library" and once you got it placed edit it and press Help button. This will tell you how to use it.