Yearly Archives: 2016


Last post we examined the Sallen-Key topology, now we get into a specialty device, namely the instrumentation amplifier. Typically constructed from several amplifiers, it has proven so effective in amplifying low-frequency differential voltages, it’s now widely available in pre-packaged form. In this case the signal being amplified is of very […]

Cooking with Op-Amps, part 12: Instrumentation Amplifiers!


We have so far stuck to the simplest cases of filters, often single-pole; is a band pass/stop filter two poles? Technically yes, but the term usually expresses the idea that both poles affect the same pass/stop frequency together, doubling the rate of attenuation. In other words, where a single pole […]

Cooking with Op-Amps, part 11: Sallen-Key Filters!


Last time around we built a simple (single-pole) high-pass filter, this time it’s band pass and band stop. One is the opposite of the other, with the frequency cut-off points adjusted accordingly; schematically they’re a little different looking though. Band-Pass This one’s the easier of the two because it’s a […]

Cooking with Op-Amps, part 10: Band Pass/Stop Filters!