Topic: Analog Circuits
For the following circuit, determine the output voltage $v_o$ in terms of input voltages $V_1$ and $V_2$ assuming $A_1$ and $A_2$ are ideal op-amps (A1 is a non-inverting amplifier with gain $1+1/10$, feeding into A2 which acts as a subtractor/amplifier)
- A. $11 V_2 - V_1$
- B. $V_2 - 11V_1$
- C. $11(V_2 - V_1)$
- D. None of the above
Answer: C. $11(V_2 - V_1)$
Explanation: For Op-amp $A_1$, it is a non-inverting amplifier: $V_{o1} = (1 + 1/10)V_1 = \frac{11}{10}V_1$. For Op-amp $A_2$, it applies a gain to both $V_{o1}$ and $V_2$. Using superposition: $V_o = -10V_{o1} + 11V_2 = -10(\frac{11}{10}V_1) + 11V_2 = 11(V_2 - V_1)$.