Rowan University
Department of Electrical & Computer Engineering
ECE 09.201.02 Networks I – First Fall Quarter 2007
Lab Project 5
Performed: 10/08/2007
Networks I - Lab Section 2: Mondays 3.15-6.00 pm
Lab Project 5 - due: next Monday – 15 October 2007
Lab 5 – The Op-Amp
Objectives: The objective of this lab is to become familiar with the use of an Op-Amp to
perform a signal processing operation. An Op-Amp can be used as both an inverting
amplifier and a non-inverting amplifier.
Part 1:
Based on the Op-Amp fundamentals learned in class, solve for the output of the inverting
amplifier in Figure 1. First, write the ideal Op-Amp equations. Next, evaluate KCL at
node A and solve for Vout/Vin (which is a calculation of the gain of the amplifier) leaving
the resistors as variables.
Figure 1 - Inverting Op-Amp
Build the circuit in Figure 1 using either an LMC662 (National Semiconductor) or an
MC4741C (Motorola) IC and measure all voltages and currents and the gain of the
circuit. Using the resistors values from your circuit evaluate the voltages, currents and
1
gain analytically. Compare the experimental results with the calculated voltages and
currents throughout the circuit. Explain any differences. Next, change both of the
resistor values and compare the gains with your calculations. Comment on your results.
Part 2:
Based on the Op-Amp fundamentals learned in class, solve for the output of the non-
inverting amplifier in Figure 2. Using the same steps in part 1, calculate all the electrical
parameters.
Figure 2 - Non-Inverting Op-Amp
Build the circuit in Figure 2 again using either an LMC662 (National Semiconductor) or
an MC4741C (Motorola) IC and measure all voltages and currents and the gain of the
circuit. Using the resistors values from your circuit evaluate the voltages, currents and
gain analytically. Compare the experimental results with the calculated voltages and
currents throughout the circuit. Explain any differences. Next, change both of the
resistor values and compare the gains. Comment on your results.
Part 3:
Finally, build all four (4) different Op-Amp circuits you created above in Mentor
Graphics, solve for the gains of all your non-inverting and inverting amplifiers
Part 4: (Extra-Credit)
Build an electronic circuit using different Op-Amps to create the linear algebra equation
below and develop a simulation of it in Mentor Graphics: (see text pages 209-213 for
assistance)
Z = 3x - 4y + 2 such that output voltage Z depends upon two other variable voltage
sources x and y
2