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Subsections

Trans-capacitor

Syntax

.TCAPacitor label n+ n- nc+ nc- expression .TCAPacitor label n+ n- nc+ nc- value {IV=initial-voltage}

Purpose

Trans-capacitor, or charge transfer device.

Probes

All probes that apply to ordinary capacitors also apply here.

Comments

N+ and n- are the positive and negative element nodes, respectively. Nc+ and nc- are the positive and negative controlling nodes, respectively. Expression is the capacitance in Farads.

The (optional) initial condition is the initial (time = 0) value of the capacitor voltage (in Volts). Note that the initial conditions (if any) apply only if the UIC option is specified on the transient command.

This device places a charge between the output nodes that depends on the voltage on its input nodes. If you parallel the input with the output, it becomes an ordinary capacitor. While the use of this device may appear straightforward, be careful. It is easy to use it in an unstable way.

It is used internally in some transistor models.


next up previous contents
Next: D: Diode Up: Circuit description Previous: C: Capacitor   Contents
Al Davis 2000-09-04