In this lab, you will design and build several operational amplifier circuits on the breadboard.

 Use -Vcc = -15V and +Vcc = +15V for all circuits.

1. Assume that Vin = 5V.  Calculate Vout.  Build the circuit shown in Figure 2 (inverting op-amp) on the protoboard. After your wiring has been checked by a lab assistant, apply a 5 volt input voltage. Measure and record Vout. Is this the value you expected to see? How close was your answer to your calculated result (do a percent difference).
 
 

2. For the circuit in Figure 3 (non-inverting op-amp), assume Vin = 5V.  Calculate Vout.  Build the circuit shown in the figure. Apply a 5 volt input voltage. Measure and record Vout. Is this the value you expected to get? How close is it to your expected value (percent difference)?

3. For the above problems (1 and 2), what is the highest and lowest input voltages you could apply to each circuit before the op-amp would "rail"?

4. Design and build a cascaded op-amp circuit with a total gain of +1/8 (Refer to your class notes for assistance, if necessary). Calculate Vout for this circuit if you were to apply a 5V input.  Apply a 5 volt input signal and record Vout. How close is your result to what you ideally would get?

5. Design and build an op-amp circuit with a total gain of 3.25. Apply a 5 volt input signal and record Vout. Record your result for Vout.

6. Design and build an op-amp circuit with a total gain of -3.25. Apply a 5 volt input signal and record Vout. Record your result for Vout.
 
 

Questions

1. How could you design a circuit to provide a gain of 1/8 to an input signal without using an op-amp?

2. In problems 5 and 6, were your outputs 3.25 (or -3.25) times the magnitude or your inputs? Explain why or why not.