A programmable-gain amplifier (PGA) is an

electronic amplifier An amplifier, electronic amplifier or (informally) amp is an electronic device that can increase the magnitude of a Signal (information theory), signal (a time-varying voltage or Electric current, current). It is a two-port network, two-port ...

(typically based on an

operational amplifier An operational amplifier (often op amp or opamp) is a direct coupling, DC-coupled Electronic component, electronic voltage amplifier with a differential input, a (usually) Single-ended signaling, single-ended output, and an extremely high gain ( ...

) whose gain can be controlled by external

digital Digital usually refers to something using discrete digits, often binary digits. Businesses *Digital bank, a form of financial institution *Digital Equipment Corporation (DEC) or Digital, a computer company *Digital Research (DR or DRI), a software ...

analog Analog or analogue may refer to: Computing and electronics * Analog signal, in which information is encoded in a continuous variable ** Analog device, an apparatus that operates on analog signals *** Analog electronics, circuits which use 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 I2C (Inter-Integrated Circuit; pronounced as "" or ""), alternatively known as I2C and IIC, is a synchronous, multi-master/multi-slave, single-ended, serial communication bus invented in 1980 by Philips Semiconductors (now NXP Semiconduct ...

while the latest PGAs can also be programmed for offset voltage trimming, as well as active output filters.PGA103
from

Texas Instruments Texas Instruments Incorporated (TI) is an American multinational semiconductor company headquartered in Dallas, Texas. It is one of the top 10 semiconductor companies worldwide based on sales volume. The company's focus is on developing analog ...

, an
MAX9939
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Maxim Integrated Products Maxim Integrated Products, Inc., was an American semiconductor company that designed, manufactured, and sold analog and mixed-signal integrated circuits for the automotive, industrial, communications, consumer, and computing markets. Maxim's p ...

Popular applications for these products are motor control, signal and sensor conditioning.

References

{{Electron-stub Electronic amplifiers