User`s guide

14
-
2 Di
g
ital Simulation
What Is Di
g
ital
Simulation?
Digital simulation is the analysis of logic and timing behavior of
digital devices over time. PSpice A/D simulates this behavior
during transient analysis. When computing the bias point,
PSpice A/D considers the digital devices in addition to any
analog devices in the circuit.
PSpice A/D conducts detailed timing analysis subject to the
constraints specified for the devices. For example, flip-flops
perform setup checks on the incoming clock and data signals.
PSpice A/D reports any timing violations or hazards as
messages written to the simulation output file and the Probe data
file.
Steps for Simulatin
g
Di
g
ital Circuits
There are six steps in the development and simulation of digital
circuits:
1
Draw schematic.
2
Define stimuli.
3
Set simulation time.
4
Adjust simulation parameters.
5
Start simulation.
6
Analyze results.
See Tracking Timing Violations
and Hazards on page 14-28 for
information about persistent
hazards, and for descriptions of
the messa
g
es.
For more information on drawin
g
schematics see the
MicroSim
Schematics User’s Guide
. Steps
2 throu
g
h 6 are covered in this
chapter.