Our cell module we're working with now uses a low-voltage IO core, and when we read the datasheet it helpfully lets us know that we should be using transistors to 'level / current shift' the LED driving outputs.

BJT's require a lower voltage to turn on, but they need resistors to help bias - which turns a single component into a 3-piece network. To make our board more compact, let's take a look at 'pre biased' transistors - they come in common packages like SOT-23 and a wide range of resistor configurations!

See the chosen part on DigiKey https://www.digikey.com/short/zr9d2j2n

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