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Sinusoidal

General Form:
sin(vo va [freq td theta phi])
Example:
vin 3 0 sin(0 1 100meg 1ns 1e10)

This function can be called as tsin to avoid possible conflict with the sin math function.

parameter description default value units
vo offset   volts or amps
va amplitude   volts or amps
freq frequency 1/tstop hz
td delay 0.0 seconds
theta damping factor 0.0 1/seconds
phi phase delay 0.0 degrees

The shape of the waveform is described by the following table:

time value
0 to td vo + va . sin($ \pi$ . phi/180)
td to tstop vo + va . exp(- (time- td) . theta) . sin(2$ \pi$ . (freq . (time- td) + $ \pi$ . phi/360 ))

This function applies only to transient analysis, where time is the running variable. When referring to default values, tstep is the printing increment and tstop is the final time in transient analysis, see 2.7.10 for explanation. The argument count is used to distinguish this function from the math function of the same name.

If this function is used bare and not part of an expression in a voltage or current source, then the general source instance parameters prm1 etc. map as below. It is possible to read and alter these values using the special vector @device[param] construct, or with the alter and sweep commands. However, there is no sanity checking so bad numbers can cause wild behavior or worse.

prm1 vo
prm2 va
prm3 freq
prm4 td
prm5 theta
prm6 phi


next up previous contents index
Next: Sinusoidal Pulse Up: Tran Functions Previous: Amplitude Modulation   Contents   Index
Stephen R. Whiteley 2019-06-03