As a service to our readers, we're providing the LTspice files used in Dr. Dyer's article on simulation of the 12AX7 and the K2-W vacuum-tube op amp. 1. The model for the K2-W is established as a ...

LTspice simulation of the K2-W Vacuum Tube Op Amp’s design reveals the mad science that created a commercial revolution in 1950s and 1960s analog computing. The K2-W's first-stage differencing ...

In the last Circuit VR we looked at some basic op amp circuits in a simulator, including the non-inverting amplifier. Sometimes you want an amplifier that inverts the signal. That is a 5V input ...

Maybe you are familiar with the op-amp as an extremely versatile component, and you know how to quickly construct a huge variety of circuits with one. Maybe you even have a favorite op-amp or two for ...

And here it is, modelled using LTSpice. It is the same circuit as the classic simple precision rectifier (set to pass the negative half-sine), but with the non-inverting input of the op-amp connected ...

This is the last of the “Yet more…” series. One final plot twist, a moderately satisfying ending, and my work here will be done. Until the sequel, that is… Let the op-amp do the pinging! Instead of ...

How do you get the input of an op-amp to work below the negative-most supply rail?, I asked. Now I know – thanks to the patience of ADI field application engineer Andreas Koch. It was not just any ...