Question

what is an operational-amplifier???
a brief description please..........

Answer 1

operational amplifier is an electronic component that amplifies the difference of the voltages provided to its two input terminals.

The amplified voltage can be expressed as,
\[V_{out} = A(V^+ - V^-)\]

Theoretically the value of A is infinity but its some very large value practically. Anyway the maximum gain that can be obtained from the output does not exceed the voltage provided to power up (Vpower) the opamp



To get a finite gain (a desired value for A) , a concept called feedback control mechanism is used. As the name implies , by this method the gain is controlled by feeding back the output signal to the input though a resister arrangment thus creating a some sort of an equilibrium.