What is a voltage follower?
1 Answer
A voltage follower, also known as a unity gain amplifier or buffer amplifier, is a basic electronic circuit that has an input and an output, and it is designed to provide an output voltage that exactly follows the input voltage. In other words, the output voltage of a voltage follower is equal to the input voltage, maintaining the same voltage level but with the ability to supply higher current.
The primary purpose of a voltage follower is to isolate the input from the output in terms of electrical characteristics. It has a high input impedance and a low output impedance, which means it presents a minimal load to the circuit driving the input and can deliver more current to the load connected to its output.
The voltage follower is typically implemented using an operational amplifier (op-amp) as the main active component. Op-amps are widely used in voltage follower configurations due to their high input impedance, low output impedance, and high gain.
Applications of voltage followers include:
Impedance matching: When the output impedance of a source is high, using a voltage follower can lower the effective output impedance, enabling better transfer of the signal to the next stage of the circuit.
Signal buffering: When a weak signal needs to be preserved and not affected by the loading effects of the next stage, a voltage follower can be used to prevent signal degradation.
Isolation: A voltage follower can provide isolation between different parts of a circuit, preventing interference between them.
Active filters and amplifiers: In some filter or amplifier designs, a voltage follower can be used to isolate stages or set the gain without significantly affecting the overall performance.
Overall, the voltage follower is a straightforward but essential building block in electronics that finds application in various circuits where signal integrity and impedance matching are crucial.
The primary purpose of a voltage follower is to isolate the input from the output in terms of electrical characteristics. It has a high input impedance and a low output impedance, which means it presents a minimal load to the circuit driving the input and can deliver more current to the load connected to its output.
The voltage follower is typically implemented using an operational amplifier (op-amp) as the main active component. Op-amps are widely used in voltage follower configurations due to their high input impedance, low output impedance, and high gain.
Applications of voltage followers include:
Impedance matching: When the output impedance of a source is high, using a voltage follower can lower the effective output impedance, enabling better transfer of the signal to the next stage of the circuit.
Signal buffering: When a weak signal needs to be preserved and not affected by the loading effects of the next stage, a voltage follower can be used to prevent signal degradation.
Isolation: A voltage follower can provide isolation between different parts of a circuit, preventing interference between them.
Active filters and amplifiers: In some filter or amplifier designs, a voltage follower can be used to isolate stages or set the gain without significantly affecting the overall performance.
Overall, the voltage follower is a straightforward but essential building block in electronics that finds application in various circuits where signal integrity and impedance matching are crucial.