Operational Amplifier Fundamentals Unit 4 – The Voltage Follower
UNIT 4 – THE VOLTAGE FOLLOWER
UNIT OBJECTIVE
At the completion of this unit, you will be able to operate an operational amplifier circuit
configured as a voltage follower or a gain-of-one inverting amplifier.
UNIT FUNDAMENTALS
A voltage follower circuit has unity gain, which means it has a gain of 1.
A voltage follower is also called a unity gain amplifier.
Advantages of a voltage follower are high input impedance, low output impedance (good
impedance matching characteristics), wide bandwidth, and fast response.
In a voltage follower configuration, the op amp output terminal is directly connected to the op
amp inverting input terminal. As a result, all of the output voltage is fed back.
Due to the input/output connection, the output voltage (VO) follows the circuit input voltage
(VI) in magnitude and polarity.