MultiSimtutorial2.pdf

Introduction to MultiSim Î Part 2

Prepared by:

Mohamad Eid

Summer 2007

The purpose of this tutorial is to demonstrate the use of MultiSim to simulate operational

amplifier circuits (uA741 OpAmp), such as inverting and non-inverting amplifiers, filters,

and oscillators. The circuit shown in Figure 1 is used as a simulation example in the

current tutorial.

Figure 1. An inverting unity gain operational amplifier circuit

1) Start the MultiSim program as shown in the previous tutorial (For Windows users the

default location can be found by clicking: Start ->All Programs -> Electronics

Workbench -> DesignSuite Freeware Edition 9 -> MultiSim 9).

2) You will be creating a new schematic and simulation so choose File->SaveAs,

navigate to or create a directory where you can save this schematic and simulation then

fill in the filename as shown below. (I called this one tut1.) Click OK when you have

navigated to the proper directory and entered a name for the project.

3) You should now have a blank schematic. Start placing components by selecting Place-

>Component from the menu bar. You will see another dialog box as shown. Start with

the OpAmp so pick Analog Components in the drop down menu as shown:

4) You should see a new dialog box. Select OPAMP then LM741CN as shown below then

click OK.

5) Place the OpAmp on the schematic. Next you must add a couple of power supply

connections. You will add a DC source by again selecting Place->Component. Only this

time pick SOURCES from the drop down menu. Then select POWER_SOURCES and

DC_POWER as shown below then click OK.

6) Put the battery (DC power source) on the schematic somewhat above the OpAmp as

shown below.

7) Double click on the Ð12VÑ. Change the voltage from 12 to 18 then click OK.

8) Place the rest of the components on the schematic as shown below. Use Place->Wire

to add wires for connecting components together. Resistors are under the Basic

components drop down menu. Note you must specify Ðk _ Ñ in the filter to locate the 10K

resistors. Note GROUND symbols are at SOURCES->POWER_SOURCES. Your

completed schematic should resemble the one below.

9) Be sure all components are connected as shown above. Now you will name the input

and output signals to make them easier to locate in simulation. First highlight the wires

above the 5V 1KHz source V3. Do this by placing the cursor on the red wire and left

clicking once. Now right click once and select ÐpropertiesÑ from the popup menu.

Change the net name to Vin as shown on the next page then click OK. Use the same

method to change the output net name to ÐVoutÑ.

10) You will now run a simulation. First select Simulate->Analyses->Transient Analysis

from the top menu bar. Change the End Stop Time (TSTOP) to 0.002 as shown below.

11) Next choose the Output page and select the two signals you want to see on the output.

Your dialog box should now look like the one on the next page.