Q. Applications of operational amplifiers?

An op amp along with a few external components (resistors and capacitors) is capable of performing many different operations-hence the name operational. The linear operations of integration, differentiation, addition, and subtraction that were needed in analog computers are some of the early applications. Other linear applications include instrumentation amplifiers, voltage-to-current and current-to-voltage converters, voltage followers, and active filters. Op amps are also utilized in nonlinear applications such as limiters, comparators, voltage regulators, signal rectifiers and detectors, logarithmic amplifiers, multipliers, and many digital circuits. Negative feedback (which is said to be degenerative) is used to improve amplifier performance by sacrificing gain. The opposite situation of positive feedback (which is said to be regenerative) is also utilized, and gain is increased to the extent that an amplifier will produce an output signal with no input. This leads to sinusoidal oscillators and nonsinusoidal waveform generators. This section concentrates on a limited range of op-amp applications.