How does An Operational Amplifier Work?
An operational amplifier is an extremely high gain differential voltage amplifier—a device that compares the voltages of two inputs and produces an output voltage that’s many times the difference between their voltages. How the operational amplifier performs this subtraction and multiplication process depends on the type of operational amplifier, but in most cases two input voltages control how current is shared between two paths of a parallel circuit. Even a tiny difference between the input voltages produces a large current difference in the two paths—the path that’s controlled by the higher voltage input carries a much larger current than the other path. The imbalance in currents between the two paths produces significant voltage differences in their components and these voltage differences are again compared in a second stage of differential voltage amplification. Eventually the differences in currents and voltage become quite large and a final amplifier stage is used to produce ei
