User`s guide

Noise Analysis 10
-11
Settin
g
Up a Noise Anal
y
sis
To set up the noise anal
y
sis
1
From the Analysis menu, select Setup.
2
Click AC Sweep.
3
In the AC Sweep dialog box, set up an AC sweep analysis
as described on page 10-5
.
4
In the AC Sweep dialog box, select (
✓) the Noise Enabled
check box.
5
Enter the noise analysis parameters as follows:
6
Click OK.
In this text
box...
Type this...
Output Voltage A voltage output variable of the form
V(node, [node])
where you want the
total output noise calculated.
I/V Source The name of an independent current or
voltage source where you want the
equivalent input noise calculated.
Note If the source is in a lower level of
a hierarchical schematic, separate the
names of the hierarchical devices with
periods (.).
Interval An integer n designating that at every n
th
frequency, you want to see a table
printed in the PSpice output file (.out)
showing the individual contributions of
all of the circuit’s noise generators to the
total noise.
To find out more about valid
syntax, see
Output Variables on
page 8-5.
Example: U1.V2
Note
In Probe, you can view
the device noise contributions
at every frequency specified
in the AC sweep. The Interval
parameter has no effect on
what PSpice A/D writes to the
Probe data file.