User Guide

Chapter 11 Parametric and temperature analysis
274
RLC filter example
This example shows how to perform a parametric sweep
and analyze the results with performance analysis.
Use performance analysis to derive values from a series of
simulator runs and plot these values versus a parameter
that varies between the simulator runs.
For this example, the derived values are the overshoot and
the rise time versus the damping resistance of the filter.
Entering the design
The schematic representation for the RLC filter
(RLCFILT.OPJ) is shown in Figure 68.
This series of PSpice runs varies the value of resistor R1
from 0.5 to 1.5 ohms in 0.1 ohm steps. Since the
time-constant of the circuit is about one second, perform a
transient analysis of approximately 20 seconds.
Create the circuit in OrCAD Capture by placing a
piecewise linear independent current source (IPWL from
SOURCE.OLB). Set the current source properties as
follows:
AC = 1a
T1 = 0s
I1 = 0a
T2 = 10ms
Figure 68 Passive filter schematic.
Pspug.book Page 274 Wednesday, November 11, 1998 1:14 PM