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by philsnow 1315 days ago
Usually when I read through a build-out description like this, the author writes it for an audience that has a lot more background knowledge than I do. This article, on the other hand, was lucid and the explication helped me follow along.

I got to the part about 3.3V being derived from 5V and thought to myself "why not get it from 24V?" and then just a tiny bit later, there's the bit about USB and how Starfish can just take 5V from the USB host, and it clicked.

I also learned about Sparkfun's QWIIC connector in the aside about the chosen i2c bus switch having two "extra" channels. Love it, thanks for the article, Thea.

1 comments

Thank you for the kind words! I'm glad it was useful.

> why not get it from 24V?

There are DC-DC converters in that same family that can do 4.75~36V -> 3.3V, but since I needed the 5V anyway for the LEDs and I/Os, tossing an inexpensive and small LDO for 5V -> 3.3V is an easy call.