The operational amplifier is arguably the most useful single device in analog electronic circuitry. When you apply them in the circuits, you must know their basics and functions. As for the function ...

As the name implies, if we finally put together all the elementary blocks above (transistors, current mirrors, current sources, differential stages and buffers) we finally come to something usable, ...

My hands-on introduction to operational amplifiers was in 1969 while in the army as a junior scientist in the Atmospheric Science Laboratory at the White Sands Proving Grounds. We had taken a ...