When you design an analog, lowpass, antialiasing filter, you would expect its gain amplitude to continuously decrease beyond the filter's cutoff frequency. For the most part, this assumption is a safe ...

Setting out to design a higher order, high pass filter using the Sallen-Key single op amp topology will immediately run into a question of required amplifier bandwidth. This is most often set by the ...

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 ...

Michael Steffes challenges conventional approaches to Sallen Key Filter design. He says today's components and VFAs offer greater flexibility. This opinion piece links to more detailed explanations.

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 ...

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 ...

My previous column described the Sallen-Key circuit for a low-pass filter. At times, you will not find a low-pass filter with the specifications you need in an anti-alias circuit, so you might decide ...