Inductor Labels

Set the inductor value, and other goodies here. Use the US or the Brit. conventions for the capacitance value. e.g.

2.2u = 2.2u = 2U2 = 2u2 = 2200 = 2.2e-6

In addition, inductors support temperature co-efficients. These are, TC1 and TC2:

L = Lo*(1 + tc1*(Tckt - Tnom) + tc2*(Tckt - Tnom)2 )

Tckt is the operating temperature of the circuit, specified in the main temperature setup dialog or spice options. Tnom is the temperature that the co-efficients of all spice devices are measured also setup in the spice options, and defaults to 27 deg. C.

Example netlist:

L1 1 2 12u tc1= 2.5m tc2=1.5u

These values are usually set automatically using the GUI dialog setups.

Inductor Model

Inductors may also be specified within .subckts by use of a model, for example:

.subckt cored_transformer 0 1 2 3
*
L1 1 2 indx nt=100
L2 3 4 indx nt=200
K1 L1 L2 0.99
.model indx L(area=20u length=3e-2 mu=125)
.ends

Available model parameters:

nt = "number of turns"
area = "mean cross sectional area of the core"
length = "mean magnetic path length"
mu = "relative permeability"
ind = "actual inductance"

This can be useful in constructing more complicated transformers rather than individually specifying inductances.

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