In my previous article on common op-amp circuits, I mentioned that operational amplifiers were used for analog computing, where analog circuits simulated the behavior of complex systems. That article ...

Bob Pease got an e-mail in 2006 from an engineer who was having trouble with an integrator circuit. Amplifiers are often called op amps because they were originally used as operational amplifiers.

On two days in the course of every year, one in March heralding the start of spring and another in September marking the first of fall, the Earth’s axis of rotation aligns perpendicular to the rays of ...