Thermistors
SuperSpice directly supports two extensions to Spice3/XSpice with regard to thermistors.
1 Exponential variation of Resistors
The following formula is implemented:
R(T) = rsh.e(tcexp(1/T-1/tnom))
Example model:
.model AnyThermistorExpName r(rsh=2.5k tcexp=1k tnom=25)
This thermistor symbol is in the Discretes folder named "ThermistorExp", and is attached to a default model.
2 Steinhart Hart
The following formula, transposed for R, is implemented:
T=1/( tca + tcb.ln(R) + tcc.ln(R)3)
.model AnyThermistorSteinhartName r(rsh=01 tca=1.65988m tcb=239.678u tcc=116.809n)
rsh is a flag and must be included.
This thermistor symbol is in the Discretes folder named "ThermistorSteinhart", and is attached to a default model.