February 2019 StudentZone Quiz Solution

Question:

Compute the cut-off frequency for the RC filters above and compare the values with the measured results and simulation results. Explain any differences.

Answer:

Considering the values used in the lab experiment R1 = R1 = R1 = 1 KΩ, C1 = C2 = C2 = 0.1µF we can compute the cut-off-frequency range as follows:

3rd order RC filter cut-off frequency:

What can you notice with respect to the attenuation results in the experimental setup at the computed cutoff frequency? Is the attenuation value the expected one?