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Sinusoidal Pulse

General Form:
spulse(vo vp [per td decay])
Example:
vin 1 0 spulse(0 1 25ns 40ns 1e8)

parameter description default value units
vo offset   volts or amps
vp peak amplitude   volts or amps
per period tstop seconds
td delay 0.0 seconds
decay decay const 0.0 1/seconds

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

time value
0 vo
td vo + 0.5 . (vp- vo)( 1 - cos(2$ \pi$ . (time- td)/per) . exp(- (time- td) . decay) )

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.

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 vp
prm3 per
prm4 td
prm5 decay


next up previous contents index
Next: Table Reference Up: Tran Functions Previous: Sinusoidal   Contents   Index
Stephen R. Whiteley 2024-10-26