Voltage follower
A voltage follower is an electrical circuit which, as an active electrical component, performs an impedance conversion. Voltage followers have a theoretical voltage gain of one.
The aim of the voltage follower is to load a voltage source as little as possible and at the same time to generate an equally large but resilient voltage. Voltage followers can be found in measuring devices with high input resistance, but also in impedance converter circuits in audio engineering . Voltage followers are the basic circuit of some power supplies .
Operational amplifiers (OPV) are typically used for this purpose and switched as shown in the diagram opposite. The voltage U e denotes the input voltage, which is tapped at high resistance. U a is the output voltage. With operational amplifiers, input resistances in the giga-ohm range and, at the same time, output resistances in the ohm range can be implemented.
The "High-Speed Buffer" TI BUF634 is a voltage follower IC that is optimized for higher voltage rise speed and higher output current than the operational amplifier and is based on this basic circuit.
Individual evidence
- ↑ Data sheet of the BUF634 from Texas Instruments (PDF; 1073 kB)