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Milwaukee School of Engineering
Electrical Engineering & Computer Science Department
EE-2705 – Linear Circuits I: DC
Experiment 2
Computer Circuit Simulation – Multisim for DC Analysis
(adapted from that used in EE-2050)
Name:
Lab Partner:
Date:
Objectives:

To learn how to use a computer-based simulation program (Multisim) to analyze DC electric
circuits. The same simulation techniques also help in designing circuits.
Background: In engineering, computer software is used extensively in the analysis and design of
electrical and electronic circuits. Computer simulations are one of the fundamental tools that allow
you to quickly and accurately determine how a circuit functions – especially in advance of actually
constructing it.
Pre-laboratory Requirements:
 If Multisim is not already installed on your laptop, login to the MSOE network and install
Multisim 14.0 (or the most current version). Verify a successful install before coming to
lab.
 Calculate the currents and voltages associated with the circuit shown on page 4 and record
these values directly in Table 1 or within your laboratory notebook.
Needed Equipment and Parts:

Before coming to lab, go to Tech Support and check out the following (one set per two
person team): breadboard, parts box, and hook-up wire.
Procedures:
1. Launch Multisim and verify that the
circuit workspace appears and that the
blue buttons associated with the virtual
toolbar appear in the upper right. If they
are not enabled, then use View /
Toolbars to enable it.
Multisim uses both virtual components
and power sources which can be set to
any valued desired. In this way, any
circuit can be readily constructed and
tested.
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2. Constructing a virtual voltage divider circuit:
a. In the Virtual Toolbar, click on Power Source
Components:
e
b. Click the DC Power Source icon and then click the
workspace to place it in the drawing. Double-click it to
change its “Voltage (V)” value to 10 volts.
c. In the Virtual Toolbar, click on Basic Components:
Click on the Resistor and place one on the drawing. Do
the same to place a second one. To rotate the second one, right-click it and select “rotate 90
clockwise.” Change the resistors to 2k and 3k as shown.
d. From the Power Source Components
window on the Virtual Toolbar, choose
Ground and place it on the drawing at
the location at the circuit’s reference
node.
Now, wire the components
together by clicking the first node, and
then clicking the next node.
e. Also, about two-thirds of the way down
the right-hand Instrument Toolbar,
click the Agilent Multimeter, and then
place it on the drawing. Double-click
the instrument icon to see the photo.
Connect the icon as shown. Note how
the terminals on the icon are positioned as on the real instrument.
f. Turn on the Agilent Multimeter by clicking its Power button, and then press DC V to measure
DC volts.
g. Finally, click the “0/1” simulation on/off switch at the far upper right of the screen
to start the simulation. After a few seconds the Agilent Multimeter should read the
voltage (6 volts).
h. Stop the simulation and delete the Agilent Multimeter. Now, use a Measurement
Probe: which is in the Instrument Toolbar, near the bottom.
i.
Run the simulation and note how the Measurement
Probe list box shows the voltage and current:
j.
Component abbreviations such as k (for kilo), u (for
micro) and m (for milli) can be used.
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k. Try the multimeter, at the top of the Instrument Toolbar, as a DC voltmeter (left), and also as
a DC ammeter (right). Note how the connection is broken to insert the ammeter (DC is chosen
using the “----“ button):
l.
While this experiment is not using any controlled sources, if it did you could click on the “Place
Source” symbol at the upper left of the screen. This will show a complete set of components in
the Library. From that you can select a controlled source of any type. Note the diamondshaped source, and the rectangular “sensor”, both of which would need to be connected.
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Laboratory Assignment:
1. Construct the circuit shown in Multisim.
Then ‘measure’ the currents I1-I3 and the
node voltage, 1. Record these values in
the Table 1 below. Do not yet close out
Multisim.
2. Now, physically construct this circuit on your breadboard. Before connecting the resistors,
however, measure the actual resistances associated with R1-R3 and record these values on
the schematic. Set the DC supply to 12.0 vdc and power up your circuit. Measure and record
the node voltage 1. Show how you can now derive the currents I1-I3 and record these values
in Table 1.
3. Return to your Multisim circuit and replace R1-R3 with their actual measured resistance
values. Rerun the simulation and record the currents I1-I3 and the node voltage, 1 in the table
shown.
4. Compare and comment on the similarities and differences between your (pre-lab) calculated,
simulated, and measured values.
Table 1.
Component Pre-lab calculated
Simulated
results
results
Voltage Current Voltage Current
R1
Measured
results
Voltage Current
Re-simulated
results
Voltage Current
R2
R3
Consider also using Multisim to simulate and check any of your homework problems –
but only after you have solved or attempted to solve them manually. It will be great
practice and further help reinforce your understanding of basic circuit principles.
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