Category Archives: Analog

One of the more interesting and frustrating issues is that of power supply sequencing.  Power supplies generally are analyzed for startup issues, but less often for other sequences of events.  This can lead to interesting failures.

Previously, I had written about an elegant circuit — the positive gain, single opamp biquad.  That circuit is rewarding to analyze, as it has multiple nice solutions.  The negative gain version is a bit more difficult to analyze.  Further, it … Continue reading →

Of all circuits, the one that has most influenced me is the 2nd order “biquad” using one opamp. This is commonly called the “Sallen-Key” biquad. This was the circuit I tried to understand and explain before even taking a class … Continue reading →