Programmable-gain amplifier
A programmable-gain amplifier is an electronic amplifier whose gain can be controlled by external Digital [signal (electronics)|digital] or analog signals.
The gain can be set from less than 1 V/V to over 100 V/V. Examples for the external digital signals can be SPI, I²C while the latest PGAs can also be programmed for offset voltage trimming, as well as active output filters. Popular applications for these products are motor control, signal and sensor conditioning.