4.12 SIN: Sinusoidal time dependent value
4.12.1 Syntax
SIN args
SIN offset amplitude frequency delay damping
4.12.2 Purpose
The component value is a sinusoidal function of time, with optional
exponential decay.
4.12.3 Comments
For voltage and current sources, this is the same as the Spice SIN function, with some extensions.
It generates either a steady sinusoid, or a damped sinusoid.
If delay and damping are both zero, you get a steady sine
wave at the specified frequency. Otherwise, you get a damped
pulsed sine wave, starting after delay and damping out with a
time constant of 1/damping.
The shape of the waveform is described by the following algorithm:
reltime = time - _delay
if (reltime > 0.){
ev = _amplitude * sin(2*PI*_freq*reltime);
if (_damping != 0.){
ev *= exp(-reltime*_damping);
}
ev += _offset;
}else{
ev = _offset;
}
For other components, it gives a time dependent value.
As an extension beyond Spice, you may specify the parameters as
name=value pairs in any order.
4.12.4 Parameters
- Offset = x
- DC offset. (Default = 0.)
- Amplitude = x
- Peak amplitude. (Default = 1.)
- Frequency = x
- Frequency, Hz. (required)
- Delay = x
- Turn on delay, seconds. (Default = 0.)
- Damping = x
- Damping factor, 1/seconds. (Default = 0.)