Hi All,
I need to create a resistor whose resistance varies according to an equation with the variables of the top and bottom voltage (ie. the voltage across it). I use Altium (was Protel) but I suspect the fundamental process is the same. My main concern is that it is what excel would refer to as a circular reference but I don't understand the inner workings of SPICE tools to know whether it's feasible.
Cheers, wombat
In PSpice this is done with behavioral models, for example "GVALUE", which is a current source written as an equation relating to the end voltages.
In other Spice's I believe these are called "B" sources.
...Jim Thompson
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In generic spice you use the "B Source".
e.g
b1 1 0 i=2.4*V(1,0) + 3.5*V(1,0)*V(1,0)*
This makes the current through nodes 1,0 be a function of the voltage across it, i.e. a non-linear resister.
You should make a .subckt model with all the details in it etc...read manual etc..
Kevin Aylward B.Sc. snipped-for-privacy@anasoft.co.uk
"There are none more ignorant and useless,than they that seek answers on their knees, with their eyes closed"
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