1. ELEC 202 Electric Circuit Analysis II
Op Amp AC Circuits
ELEC 202
Electric Circuit Analysis II

2. Assumptions Op Amp assumed to be operating in the linear region.
Op Amp assumed to be ideal having two important characteristics:
(a) no current enters neither of its input terminals;
(b) The voltage across its input terminals is zero.

3. Solving Techniques Transform the circuit into phasor domain.
Labels currents into the input terminals of
op amp and node voltages at all other nodes in the circuit.
Use Nodal analysis to solve for node voltages.

4. Example 1 Determine vo(t) for the following op amp AC
circuit with vs(t) = 3 cos 1000t V.

5. Example 1 (cont’d)

6. Example 2 Compute the closed-loop gain and phase shift
for the following circuit with R1 = R2 = 10 kW,
C1 = 2mF, C2 = 1mF, and w = 200 rad/s.

7. Example 3 Determine vo(t) and io(t) in the following op amp
AC circuit with vs(t) = 2 cos 5000t V.