User Guide

Parametric analysis
43
Setting up and running the parametric analysis
To change the value of R1 to the expression {Rval}
1 In Capture, open CLIPPER.OPJ.
2 Double-click the value (1k) of part R1 to display the
Display Properties dialog box.
3 In the Value text box, replace 1k with
{Rval}.
4 Click OK.
To add a PARAM part to declare the parameter Rval
1 From Capture’s Place menu, choose Part.
2 In the Part text box, type
PARAM (from the PSpice
library SPECIAL.OLB) , then click OK.
3 Place one PARAM part in any open area on the
schematic page.
4 Double-click the PARAM part to display the Parts
spreadsheet, then click New.
5 In the Property Name text box, enter Rval (no curly
braces), then click OK.
This creates a new property for the PARAM part, as
shown by the new column labeled Rval in the
spreadsheet.
6 Click in the cell below the Rval column and enter 1k
as the initial value of the parametric sweep.
7 While this cell is still selected, click Display.
8 In the Display Format frame, select Name and Value,
then click OK.
9 Click Apply to update all the changes to the PARAM
part.
10 Close the Parts spreadsheet.
11 Select the VP marker and press
D to remove the
marker from the schematic page.
12 From the File menu, choose Save to save the design.
PSpice interprets text in cur
l
y
b
races as an
expression that evaluates to a numerical
value. This example uses the simplest form
of an expression—a constant. The value of
R1 will take on the value of the Rval
parameter, whatever it may be.
Note
For more information about using
the Parts spreadsheet, see the OrCAD
Capture User’s Guide.
T
h
is examp
l
e is on
l
y intereste
d
in t
h
e
magnitude of the response.
Pspug.book Page 43 Wednesday, November 11, 1998 1:14 PM