Op Amps.pdf


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Inverting Amplifier
Vin (Volts) V0 (Volts)
-10
-13.949
-9
-13.960
-8
-13.972
-7
-13.846
-6
-11.871
6
11.868
7
13.245
8
13.227
9
13.209
10
13.191
Table 2: Expanded voltage across the output terminal vs. input voltage for the basic
inverting amplifier.
Then we set our source voltage to Vin = 3V. We measured the current through the input
resistor, and we measured it to be 4.355 mA.

2.2

AC Amplification with Integrators and Differentiators

We then switched our DC voltage source out for an AC voltage source, and set vin = 1Volt
with frequency of 100 Hz. A peak to peak time difference of δt = 5ms was observed between
vin and v0 .
Next we increased the amplitude of the 100 Hz input voltage to vin = 8Volts. We observed
that the output voltages reached saturation at each peak at a value of around vm ax =
±14.2Volts.
We then switched out the input resistor with one of size R1 = 9.958kΩ and our feedback
resistor with a capacitor of capacitance C = 0.1µF . This then creates an integrator with
1
= 996 × 10−6 . Refer to Figure 5 for the circuit diagram
constant of proportionality − RC
of such a circuit. We observe that as the frequency of our input voltage increases, that the
magnitude of the output voltage decreases.
We then varied the frequency of the input voltage, f , and measured the ratio of the output
voltage magnitude to the input magnitude as G = vvin0 . This data can be seen in Table 3.
Next we observed the phase shift between the output and input voltages as a function of
frequency. This data can be seen in Table 4.

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