Lab 27 Op Amp Characteristics
· To verify experimentally that the gain of an op amp can be made dependent on on the external negative feedback loop from output to input
· To operate an op amp as a noninverting amplifier
· To operate an op amp as a inverting summer
-Dual power supply
-741C op amp Data Sheet
-741C op amp
1. Connect the circuit of Figure 1 (27-9). RF = RR = 10K Ohms. Close S1 and S2 are open. Set each of the two supplies to 9 V. Set the sine wave generator at 1000 Hz, zero output. Connect the oscilloscope to the output of the op amp. External trigger / sync the oscilloscope with the output from the generator
2. Close S1 and S2
3. Gradually increase the output from the signal generator just below the point where the waveform distorts. Measure and record in Table 1 the peak to peak output signal for the feedback resistors in the circuit.
4. With the oscilloscope measure and record in Table 1 the input signal v in to the amplifier (output of signal generator).
5. Compute and then record the gain of the amplifier (v out / v in).
6. Compare the phase of the input and output signals and indicate
7. Reduce the output of the generator to 0.
8. Repeat steps 3-7 for each value of RR shown in Table 1. Use a resistor decade box to set up the required value of RR.
9. Open S1 and S2.
10. Modify the circuit to conform to that in Figure 2 (27-10). The power supplies remain connected as shown previously in Figure 1. Set each at 9 V. The generator output is at 1000 Hz.
11. Close S1 and S2. For each value of RF and RR shown, complete and record the data required in Table 2, following the same procedure as in Table 1.
12. Open S1 and S2. Keep the power supplies connected as in Figure 1, each at 9 V. Modify the experimental circuit as in Figure 3 (27-11). RF = R1 = R2 = 10,000.
13. Close S1, S2, and S3. S4 is open. Measure and record in Table 3 V1 and VOut.
14. Open S3. Close S4. Repeat step 13.
15. Close s2. Both S3 and S4 are now closed. Measure and record VOut and VIn.
16. Reverse the polarity of V1. Measure and record VOut and VIn with S3 and S4 closed
17. Modify the summer circuit so that with the two 1.5- V inputs in Figure 3, vOut = -4.5 V (approx). Show the values of all resistors and V1 and V2 polarities. Measure the output voltage and record it in a specially prepared table.
18. Modify the summer circuit so that with two 1.5-V inputs, the output voltage = + 1.5-V (approx). Show and record the values of all resistors and V1 and V2 polarities.
19. Experimentally determine if there is a practical limit on the undistorted gain of the inverting op amp. Record the maximum voltage and gain.
During this lab we ran into very few problems those problem were the lack of time we had this week as well as cole had issues setting up the breadboard because he configure the pins of the op amp...