User Guide

Chapter 3 Preparing a design for simulation
68
To declare a global parameter
1 Place a PARAM part in your design.
2 Double-click the PARAM part to display the Parts
spreadsheet, then click New.
3 Declare up to three global parameters by doing the
following for each global parameter:
a Click New.
b In the Property Name text box, enter NAMEn, then
click OK.
This creates a new property for the PARAM part,
NAMEn in the spreadsheet.
c Click in the cell below the NAMEn column and
enter a default value for the parameter.
d While this cell is still selected, click Display.
e In the Display Format frame, select Name and
Value, then click OK.
Note
The system variables in Table 11 on page 3-73 have reserved
parameter names. Do not use these parameter names when
defining your own parameters.
4 Click Apply to update all the changes to the PARAM
part.
5 Close the Parts spreadsheet.
To use the global parameter in your circuit
1 Find the numeric value that you want to replace: a
component value, model parameter value, or other
property value.
2 Replace the value with the name of the global
parameter using the following syntax:
{ global_parameter_name }
The curly braces tell PSpice to evaluate the parameter
and use its value.
Note
For more information about using
the Parts spreadsheet, see the OrCAD
Capture User’s Guide.
Examp
l
e: To
d
ec
l
are t
h
e g
l
o
b
a
l
parameter
VSUPPLY that will set the value of an
independent voltage source to 14 volts,
place the PARAM part, and then create a
new property named
VSUPPLY
with a
value of
14v
.
Examp
l
e: To set t
h
e in
d
epen
d
ent vo
l
tage
source, VCC, to the value of the VSUPPLY
parameter, set its DC property to
{VSUPPLY}
.
Pspug.book Page 68 Wednesday, November 11, 1998 1:14 PM