Tag Archives: electronics

Sideband #76: Fun with Op Amps

Last November I posted about electronics “shortcuts” — rules of thumb that help interpret, even design, a circuit. These are approximations of more complex behavior but work well enough for a first cut at understanding a circuit.

Do not confuse these electronics shortcuts, which are generally good, with electronic short-circuits, which are almost always bad. While both offer shorter paths, that’s not a good thing in the latter case. Sometimes the journey is the only reward.

I intended to continue with op amps but kept putting it off. There are other Sidebands pending, though, so it’s time to drop the other shoe.

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Sideband #75: Electronic Shortcuts

My notes don’t include what triggered the thought, but I think it was something in one of the Lee Smolin books I read recently. My recent post, Analog Computing, brought the idea to mind again, because analog computers often use op amps. I was reminded yet again while reading about SPADs.

I’m talking about the very useful rules of thumb (heuristics) I learned to help understand, even design, electronic circuitry. They’re shortcuts in the sense of being only approximately true, but their simplified view can make a circuit much easier to understand.

I thought I’d pass them on for those interested in electronic design.

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Sideband #59: Running Hot

running hotAs a diversion for the weekend: Have you ever wondered why computers run so hot? No? Okay, I’ll tell you. It’s actually kind of a hoot. (We’ll get back to the more serious topic of algorithms and AI, and wrap up that series, next week.)

You kind of have to wonder. Humankind has gone from oil and gas lamps, to incandescent copper filaments, to fluorescent lights, and now to LEDs. The trend here seems towards cooler more efficient light sources. But computers seem to need bigger and bigger fans!

The short answer: It’s all those short circuits!

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