Hello guys!
I’m happy to say that I’m a proud owner and yesterday I’ve got my first Arduino
I have knowledge of electronics and engineering but yesterday I was soooo happy to finally play around with my board I decided to make a simple code for switchable LED’s.
I know that the board has protections but from my excitement I didn’t put resistors to the LED’s.
I know that this can hurt the LED’s if put to extended period of time.
I’m really frustrated now and want to ask you guys, from this single use is there anything bad to happen to my Arduino board?
It sounds silly from a engineering point but I really appreciate my hardware and everything I do.
Afterwards I tested the board with probably 5-6 different projects with LED’s attaching resistors and everything went perfectly.
I’m so happy to be able to use this amazing invention and I can’t wait to make thousands of projects.
Since it's apparently still working, you got away with it - for now. You may have reduced the lifetime of the digital pins you used, just remember it when you're scratching your head later trying to figure out why some pin isn't giving you the results you need.
It's a good reason to have more than one, so you can check whether the Arduino itself is the problem you're trying to debug.
It's not a voltage limit, it's a maximum current spec. The spec is 40mA "absolute maximum" from each pin and 200mA total. Most people recommend 20mA maximum.
The output voltage is either 5V (approximately) when high or 0V (approximately) when low. But as you increase the current the output-voltage actually drops (when high) so you're no longer getting 5V.
LEDs are non-linear (like all diodes). As you exceed the normal forward operating voltage (usually 2 or 3V depending on the color) the LED's resistance drops quickly and current increases by a lot.
Usually, the Arduino doesn't supply enough current to fry the LED (the output voltage drops), and the Arduino will probably survive too but it might get hot. If you connect the LED directly to a 5V power supply without a resistor the LED will burn-up, and possibly short-out and then possibly burn-up the power supply.
