A diode is specified by using two command lines. The first line defines the diode element line and the second one is the diode model.

Element line:

Dname N+ N- MODName

The element name start with D to indicate that the element is a diode, N+ and N- are the two node numbers and MODName is the name of the model of the diode which is specified in the model line.

Model line: .

MODEL MODName D (IS=value N=value)

MODName is the same name as in the element line. D indidate the the model is a diode (as opposed to a transistor), and IS is the saturation current IS and N is the ideality factor.

Lets simulate the following rectifier circuit to illustrate this. The diodes have a IS=0.01pA and n=1.

rectifier example

vin 2 0 sin(0 170 60 0 0)

rl 5 0 500

rs 2 1 10

L1 1 0 2000

L2 3 0 20

K1 L1 L2 0.99999

D1 3 5 mod1

.model mod1 D (IS=1e-14, n=1)

.tran 0.2m 20m

.plot tran v(3), v(5)

.end

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