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Hey all,

I am relatively new to this software, so I may just be missing something simple. I am having trouble using the parameters elements as I intend.

My main conclusions are that time cannot be used as a variable in a parameter element, and similarly the variables in a parameter element cannot be references from voltages/current within the CCT (i.e. a parameter element cannot be some algebraic function that includes voltage reference, V(NODENAME)). On the same note, it appears as though other referencing resistor values (i.e. R1.R) in a voltage source (for example) is not an option either. Does this have something to do with units? Or am I correct as to the above limitations?

This all stems from wanting to model a temperature dependent resistance, where temperature changes with time (i.e. a sweep). The CCT then controls a PWM signal which gets filtered and amplified to provide current control to the said temp. dependent resistor. However my simulation required a time-domain based simulation (as opposed to a DC sweep) since there is analog filtering and some feedback control as well.

Am I correct in my above statements regarding the limits to parameter elements and components values? If so, does anyone have any suggestions as to how I may be able to work around this?

Thanks, Nate