Operational Amplifier As Logarithmic Amplifier

Operational Amplifier As Logarithmic Amplifier

Operational Amplifier As Logarithmic Amplifier

• An operational amplifier can be configured to function as a Logarithmic amplifier, or simply Log amplifier.
• Log amplifier is a non-linear circuit configuration, where the output is K times the logarithmic value of the input voltage applied.
• Log amplifiers find the applications in computations such as multiplication and division of signals, computation of powers and roots, signal compression and decompression, as well as in process control in industrial applications.
• A log amplifier can be constructed using a bipolar junction transistor in the feedback to the op-amp, since the collector current of a BJT is logarithmically related to its base-emitter voltage.