If i power a 3v led, lets say an XM-L2, with 12V but limit the current to 100mA, what happens?
I know the LED can handle the power but i have no idea how much voltage they can handle when it’s not causing too much current to flow.
If i power a 3v led, lets say an XM-L2, with 12V but limit the current to 100mA, what happens?
I know the LED can handle the power but i have no idea how much voltage they can handle when it’s not causing too much current to flow.
Its impossible. Voltage will stay, lets say at 2.7V
Interesting. What happens to the excess voltage then?
Current limiting is done by limiting the voltage. Current flows because there is a voltage.
So if i power the LED through a resistor from a 12v battery the resistor will cause the battery to only provide 2.7V?
Thanks, i didn’t realise that was possible. But it’s pretty cool.
Edit: - I look like i’m talking to myself because a couple of the comments that affected my responses have been removed…
https://www.youtube.com/results?search_query=led+resistor+
Here calculator
BTW you can connect resistor to any leds leg
Ah, the resistor drops the voltage, that makes more sense. I think i misunderstood what you and Thefreeman were saying.
Thanks to you both
The resistor “drops” the voltage because it passes a specific amount of current per voltage. On the other hand the LED drops a specific voltage (forward voltage) for a current. In total the combination of LED and resistor distributes the voltage on the two components so that they pass the same current.
This is very inefficient for higher currents btw. and the resistor has a limit of how much power it can dissipate. If the current gets too high, it will heat up too much and burn out.
no the battery will still be 12 but the resistor will have 12-2.7 on it
more or less
{also wasting a lot of energy, depending on its resistance}
This would be a good one for the No stupid questions thread.
If you limiting current, you will not overvoltage the led, but if you power it by an ac adapter 12v 100ma, then who knows, depends on a adapter,