User`s guide

11
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8 Transient Analysis
Definin
g
Stimuli
1
Place stimulus part instances from the symbol set: VSTIM,
ISTIM, interface ports (IF_IN and INTERFACE), and
DIGSTIM.
2
Double-click the source instance to start the Stimulus
Editor. When you are asked whether you want to edit the
named stimulus, click OK.
3
Fill in the transient specification according to the dialogs
and prompts.
Piecewise linear and digital stimuli can be specified by
direct manipulation of the input waveform display.
4
Save the edits by selecting Save from the File menu.
Example: piecewise linear stimulus
1
Open an existing schematic or start a new one.
2
Select Get New Part from the Draw menu and either browse
the
source.slb Symbol Library file for VSTIM (and select
it), or type
VSTIM in the Part text box.
3
Place the symbol. It looks like a regular voltage source with
a STIMULUS attribute displayed.
4
Double-click the STIMULUS label and type
Vfirst. This
names the stimulus that you are going to create.
5
If you are working in a new schematic, use Save As from the
File menu to save it. This is necessary since the schematic
name is used to create the default stimulus file name.
6
Double-click the VSTIM symbol. This starts the Stimulus
Editor and displays the New Stimulus dialog box. You can
see that the stimulus already has the name of Vfirst.
7
Select PWL in the dialog box and click OK. The cursor
looks like a pencil. The message in the status bar at the
bottom of the screen lets you know that you are in the
process of adding new data points to the stimulus. The left
end of the bottom status bar displays the current coordinates
of the cursor.
See Chapter 14,Digital
Simulation, for detailed
information about creatin
g
di
g
ital
stimuli.