A voltage follower is a unity-gain buffer amplifier with high input impedance and low output impedance.
Vout = Vin × 1
A voltage follower (also called a buffer amplifier) is a special case of a non-inverting amplifier with a gain of 1. It provides:
Voltage followers are commonly used for impedance matching, isolation between stages, and as buffers for sensitive signals.
In the ideal case, the output exactly follows the input. In practice, there may be slight deviations due to: