it would have to be the operational amplifier. The humble op-amp can be configured into so many circuit building blocks that it has become an indispensable tool for designers. It’s tempting to ...

There are, of course, many other types of amplifiers, as well as other reasons to use op amps such as oscillators, filters, and other even more exotic circuits. We’ll talk about some of them ...

One circuit that may be used to realize a general biquadratic transfer function, and of course can be used to realize special-case low-pass, high-pass, band-pass, and band-reject functions, is shown ...

After a brief review of the history of the K2-W vacuum-tube op amp, an LTspice model is used to create its schematic in ...

In the late 1940s and early '50s, this original op amp circuit was constructed using several vacuum tubes, to form a multistage amplifier block. Julie's best design, known as the K2W, was adopted by ...