Analog and electronic circuits

Which correctly describes a voltage follower using an op-amp?

  1. AIts voltage gain is 1, with high input impedance and low output impedance, so it is used as a buffer
  2. BIt is used as a comparator with infinite voltage gain
  3. CIt is used as a circuit that converts input current to voltage
Show answer and explanation

Answer: A. Its voltage gain is 1, with high input impedance and low output impedance, so it is used as a buffer

A voltage follower connects the output directly to the inverting input, so the output voltage equals the input voltage (gain of 1). It does not amplify voltage, but it can drive a load without burdening the signal source, so it is used as a buffer for impedance conversion.

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