In the last edition of Don’t Fear the Filter, we built up two examples of the simplest and most-used active filter of all time: the two-pole Sallen-Key lowpass. This time, we’re going to put two of ...

Most references for calculating the components of a second-order Sallen-Key section given the complex conjugate pole locations do not present a simple closed form of equations to realize any gain with ...

Editor’s note: This article is a follow-up to the 2011 article, ‘Design second- and third-order Sallen Key filters with one op amp’ on EDN. Author’s Note: The author is revising this article to ...

There comes a time in every electronic designer’s life when, whether they know it or not, they need an analog filter in their design. If you’re coming from a digital background, where everything is ...

Recently, people in various publications have been pointing out that using an ordinary op amp in a Sallen-Key filter can cause problems. A typical op-amp circuit, as shown in Figure 1, can have a ...

Imperfect Amplifiers, Parasitic Capacitance, And Component Selection All Impact Filter Performance At High Frequencies. Since professors R.P. Sallen and E.L. Key described it in 1955, the Sallen-Key ...

I was concocting a rather silly low-pass filter design, when I remembered that Messrs Sallen and Key did it better in the 1950s, and decided to use their two-pole design to implement a Butterworth ...