Difficulty: Easy
Correct Answer: Cannot be determined from the information provided
Explanation:
Introduction / Context:
In analog electronics, an op-amp differentiator is a specific closed-loop configuration that produces an output proportional to the time-derivative of the input voltage. The classic inverting differentiator uses a capacitor in series at the input and a resistor in the feedback path. Without seeing the actual schematic, a caption like “this circuit is a differentiator” is not verifiable. This repaired question checks whether you can recognize when data is insufficient, while recalling what makes a differentiator distinct from other op-amp stages such as integrators or amplifiers with standard RC shaping networks.
Given Data / Assumptions:
Concept / Approach:
The canonical inverting differentiator satisfies Vout = −Rf * Cin * d(Vin)/dt under small-signal, linear conditions. In practice, differentiators include added series/parallel resistors or capacitors to stabilize noise gain and limit high-frequency amplification. Determining whether a given schematic realizes this function requires inspection of the input/feedback elements and the intended bandwidth constraints.
Step-by-Step Solution:
Verification / Alternative check:
If a schematic were available, write the transfer function using impedance algebra: Z_in = 1/(s*Cin), Z_f = Rf, so Vout/Vin = −Z_f/Z_in = −Rf * s * Cin, which is proportional to s (d/dt). Absent the diagram, the transfer cannot be derived.
Why Other Options Are Wrong:
Common Pitfalls:
Assuming any op-amp plus an RC is a differentiator; confusing integrator (input resistor, feedback capacitor) with differentiator (input capacitor, feedback resistor).
Final Answer:
Cannot be determined from the information provided
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