TinyZero with LED

[GrandPoohbah]

When I connect an LED to an Arduino digital pin, I usually put a 220-ohm resistor in series. However, since the TinyZero is 3.3v instead of 5v, is that still necessary?

[ZLee]

It depends on the voltage drop of your LED. Most likely, you will still need a small resistor.

However, if the voltage drop is very near 3.3v, which is quite possible with a white LED, then you will not need the resistor.

[HunterHykes]

Almost every LED has about a 0.7V voltage drop across it. You should always use a current limiting resistor in series with any LED. There are specific resistances for each color LED as the current required for each is different. Typically a resistor from about 300 ohms to 1k ohm will do the trick.

Hope this helps.