1Operational Amplifier Circuits ECE 2100 Circuit Analysis updated 11 May 2012 Pre-Laboratory Assignment 1. Consider the circuit of Figure 1. Using a hand analysis, find Vout as a function of a variable voltage source Vin assuming that the operational amplifier is not saturated (thus there is negative feedback and the op-amp input voltages track each other, that is V+ = V-). What is the gain of this amplifier circuit? 2. Use your SPICE engine to plot Vout as a function of Vin as Vin is varied from -2V to 2V. Identify the input voltage range for which the amplifier is in its linear region of operation. Explain any differences between your result of pre-laboratory part 1 and your simulation results. Verify the gain calculated in pre-laboratory part 1; place a copy of your plot (as usual) in your laboratory notebook. The NationalSemiconductorModels.lib file can be downloaded on the course website and includes a National Semiconductor SPICE model for the LM741 operational amplifier. Place this file in the same directory as your SPICE file. Figure 1. Non-inverting amplifier circuit 3. Consider the circuit of Figure 2. Using a hand analysis, find Vout as a function of a variable voltage source Vin assuming that the operational amplifier is not saturated (thus there is negative feedback and the op-amp input voltages track each other, that is V+ = V-). What is the gain of this amplifier circuit?24. Use your SPICE engine to plot Vout as a function of Vin as Vin is varied from -2V to 2V. Identify the input voltage range for which the amplifier is in its linear region of operation. Explain any differences between your result of pre-laboratory part 3 and your simulation results. Verify the gain calculated in pre-laboratory part 3; place a copy of your graph (as usual) in your laboratory notebook. The NationalSemiconductorModels.lib file can be downloaded on the course website and includes a National Semiconductor SPICE model for the LM741 operational amplifier. Place this file in the same directory as your SPICE file. Figure 2. Inverting Amplifier Circuit Procedures Part One 1. Construct the circuit of Figure 1. Carefully record measurements of Vin and Vout as Vin is varied from -2V to 2V in steps of 0.5V. Use a table. Plot the experimental data points on your curve produced in the pre-laboratory. 2. Connect your waveform generator as Vin. Connect oscilloscope CH 1 to Vin and CH 2 to Vout. Adjust the waveform generator to produce a -2V to 2V triangle waveform. Place your oscilloscope in XY mode. Adjust the settings to display the voltage transfer characteristic. Compare to the result of laboratory procedure step 1. Part Two 3. Construct the circuit of Figure 2. Carefully record measurements of Vin and Vout as Vin is varied from -2V to 2V in steps of 0.5V. Use a table. Plot the experimental data points on your curve produced in the pre-laboratory.34. Connect your waveform generator as Vin. Connect oscilloscope CH 1 to Vin and CH 2 to Vout. Adjust the waveform generator to produce a -2V to 2V triangle waveform. Place your oscilloscope in XY mode. Adjust the settings to display the voltage transfer characteristic. Compare to the result of laboratory procedure step 3. Analysis 1. Find the percentage error between the calculated, simulated, and experimental gain for each amplifier circuit. Credits and Copyright Adapted from material developed by current and former ECE faculty, including Professor Joseph Kelemen. © 2008 Damon A. Miller. All rights