Prerequisites
- Op-amp (basics)
- Bread-board connection
- Low-pass filter
- Active low-pass filter
- Quality Factor
Experiment Steps
- Connect the circuit as given in the manual.
- Obtain the cut-off frequency $f_0$ theoretically.
- Apply sinusoidal signal from a function generator at $V_i$. The sinusoidal signal should have the amplitude $3$Vp-p (peak to peak) and sweep the frequency from $\frac{f_0}{10}$ to $10f_0$.
- Measure $V_o$ voltage at each frequency. Trace the output at three frequencies ($\frac{f_0}{10}, f_0, 10f_0$).
- Calculate the following for each frequency:
Gain = $\frac{V_o}{V_i}$
Gain in DB = $20 log \frac{V_o}{V_i}$
- Plot the frequency ~ Gain in DB in a semilog graph paper.
- Repeat the above steps by replacing $R_i$ value to 10k$\Omega$. Plot the frequency ~ Gain in DB.
NEXT:
- Apply a square wave at 2kHz at the input and observe the output waveform on the CRO. Trace the overshoot at the output pulse edges. Give your comments about that.
- Do the above experiment for both $R_i = 10$ and 4.7 k$\Omega$.
