User`s guide

10
-
14 AC Analyses
Figure 10-2 shows Probe traces for Q1’s constituent noise
sources as well as total nose for the circuit after simulating.
Notice that the trace for RMSSUM (at the top of the plot), which
is a macro for the trace expression
SQRT(NTOT(Q1) + NTOT(Q2) + NTOT(Q3) + ... ),
exactly matches the total output noise, V(ONOISE), calculated
by PSpice A/D.
Fi
g
ure 10-2
Device and Total Noise Traces for
“example.sch”
To find out more about Probe
macros, refer to Probe online
help.