Programming instructions

Piecewise Linear Source
 National Instruments Corporation 1-15 Multisim Component Reference Guide
especially for large input values. Therefore, keep in mind that this source does not inherently
provide a limiting capability.
In order to reduce the potential for non-convergence of simulations, the source provides for
smoothing around the co-ordinate pairs. If
Input smoothing domain (ISD) is set to, say, 10%,
the simulator assumes a smoothing radius about each co-ordinate point equal to 10% of the
length of the smaller of the segments above and below each co-ordinate point.
1.20 Piecewise Linear Source
The Piecewise Linear Source (PWL) is available as either a voltage source or a current source.
This source allows you to control the shape of the waveform by entering pairs of time and
voltage/current values. Each pair specifies the value of the source at the specified time. At
intermediate values of time, the value of the source is determined by linear interpolation.
The component also reads a specified file which contains a table of time and current or
voltage points. Using the data in the table, the component generates a current or voltage
waveform specified by the input text file.
 To set up the PWL source:
1. Double-click on the PWL Source to open its properties dialog box.
2. From the
Valu e tab, either select the file containing the time and voltage or current points
from the dialog box or enter the data points manually.
Refer to the following for details on each type of PWL Source:
• “Piecewise Linear Voltage Source” on page 1-17
• “Piecewise Linear Current Source” on page 1-17.
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