User Guide

Chapter 13 Analyzing waveforms
334
Limiting waveform data file size
When PSpice performs a simulation, it creates a waveform
data file. The size of this file for a transient analysis is
roughly equal to:
(# transistors)·(# simulation time points)·24 bytes
The size for other analysis types is about 2.5 times smaller.
For long runs, especially transient runs, this can generate
waveform data files that are several megabytes in size.
Even if this does not cause a problem with disk space,
large waveform data files take longer to read in and take
longer to display traces on the screen.
You can limit waveform data file size by:
• placing markers on your schematic before simulation
and having PSpice restrict the saved data to these
markers only
• excluding data for internal subcircuits
• suppressing simulation output
Limiting file size using markers
One reason that waveform data files are large is that, by
default, PSpice stores all net voltages and device currents for
each step (for example, time or frequency points).
However, if you have placed markers on your schematic
prior to simulation, PSpice saves only the results for the
marked wires and pins.
Pspug.book Page 334 Wednesday, November 11, 1998 1:14 PM