Two types of switches are available: a voltage controlled switch (type SXXXXXX, model SW) and a current controlled switch (type WXXXXXXX, model CSW). A switching hysteresis may be defined, as well as on- and off-resistances ((\left. 0 < R < \infty \right)).

General form:

SXXXXXXX N+ N- NC+ NC- MODEL <ON><OFF>
WYYYYYYY N+ N- VNAM MODEL <ON><OFF>

Examples:

s1 1 2 3 4 switch1 ON
s2 5 6 3 0 sm2 off
Switch1 1 2 10 0 smodel1
w1 1 2 vclock switchmod1
W2 3 0 vramp sm1 ON
wreset 5 6 vclck lossyswitch OFF

Nodes 1 and 2 are the nodes between which the switch terminals are connected. The model name is mandatory while the initial conditions are optional. For the voltage controlled switch, nodes 3 and 4 are the positive and negative controlling nodes respectively. For the current controlled switch, the controlling current is that through the specified voltage source. The direction of positive controlling current flow is from the positive node, through the source, to the negative node.

The instance parameters ON or OFF are required, when the controlling voltage (current) starts inside the range of the hysteresis loop (different outputs during forward vs. backward voltage or current ramp). Then ON or OFF determine the initial state of the switch.