Voltage-Controlled Capacitor Spice Model now on my website

I don't have time to play with this just now, but one quick question:

Given that C is a variable capacitor, set C to 1F and charge it to 1 volt. Now change C to 0.5F. What is the new voltage?

How many 1 farad capacitors are you aware of?

Oh and would not a 1F charged cap dump into a 0.5F cap and fully charge it? If that answer is yes, then the voltage would be the same... slightly less even, all elements considered.

You thought it would morph the EMF into something else?

In LT Spice, you can use any C value. 1F is the generic capacitor. I usually normalize theoretical circuits to 1F, 1H, 1 ohm. [1]

In real life, Digikey will sell you 1F caps. Or 5000F caps. But not variable 1F caps.

I'd like to know if Jim's model conserves charge, or conserves energy, or conserves voltage. Or whatever it does.

I haven't tried that. Since it _is_ a capacitor, it'll depend on whether a simulator treats capacitors as charge-controlled devices or otherwise. ...Jim Thompson

Voltage-Controlled Resistor Spice Model Updated

See VVR.zip on the Device Models & Subcircuits Page of my website

Includes Library File (.LIB), LTspice Symbol (.ASY), PSpice Symbol (.SYM)and a JPEG showing how it was developed. ...Jim Thompson

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I've seen maybe 10 or 20 examples for sale retail. seen adverts for more.

"change", not "charge"

conservation of matter and all that.