3.19  S: Voltage Controlled Switch

3.19.1  Syntax

Device

Sxxxxxxx n+ n– nc+ nc– mname {ic}
.vswitch label n+ n– nc+ nc– mname {ic}

Model (required)

.model mname SW {args}

3.19.2  Purpose

Voltage controlled switch.

3.19.3  Comments

N+ and n– are the positive and negative element nodes, respectively. Nc+ and nc– are the controlling nodes. Mname is the model name. A switch is a resistor between n+ and n–. The value of the resistor is determined by the state of the switch.

The resistance between n+ and n– will be RON when the controlling voltage (between nc+ and nc–) is above VT + VH. The resistance will be ROFF when the controlling voltage is below VT - VH. When the controlling voltage is between VT - VH and VT + VH, the resistance will retain its prior value.

You may specify ON or OFF to indicate the initial state of the switch when the controlling voltage is in the hysteresis region.

RON and ROFF must have finite positive values.

3.19.4  Model Parameters

VT = x
Threshold voltage. (Default = 0.)

VH = x
Hysteresis voltage. (Default = 0.)

RON = x
On resistance. (Default = 1.)

ROFF = x
Off resistance. (Default = 1e12)

3.19.5  Probes

The standard probes for all basic elements are all available. See the print command for documentation.
DT
Time step. The internal time step used for this device. It is not necessarily the same as the global time step.

TIME
Time. The time of the most recent calculation of this device. It is not necessarily the same as the global time.

TIMEOLD
The time of the previous calculation of this device. It is not necessarily the same as the global time.

TIMEFUTURE
The latest recommended time for the next sample, as determined by this device. This is usually an estimate of the time the device will switch.