That was reply #55 back a few pages ago. I guess this is destined to be a perpetual thread.
I don't think we've covered the possibility of using one LED as a current limiting device for a second LED. Since the resistance of the average LED is about 120 ohms, two LEDs in series with 5v driving them would be about right wouldn't it?
That would be a "wind up", right?!
And if the forward voltage is slightly different for one of the leds , then what ?
I think it's time to wrap this one up, please.
May i ask why? i think a lot of interesting thoughts are coming from this issue
May i ask why?
or at least i hope they will learn something, rather than being stubborn
Personally, I think it's now a giant pissing contest, na-nana-nana, I know more that yoo-oooo.But that's just me.....
Because it is painfully obvious from your response that you either failed to read @raschemmel's post or you failed to understand it. Or both.In other words... https://www.google.com/search?q=talking+past+each+otherUh huh. Maybe this will help...https://www.google.com/search?q=pot+calling+the+kettle+black
I think it's probably what your mindset is about it. If it's just a pissing contest, then it should be shut down. For me i got inspiration for some led experiments i'm gonna do this weekend, mapping out how leds react to current and voltage, getting to know their behaviour even better.I also learned a lot better about how i should be careful to not damage leds (or other components) by accidentally putting too much current on them because i was thinking too much voltage wise, not current wise.I do have the impression that some people believe putting a voltage on a led and getting a sane result is impossible, and i hope they will learn that that is not right either. .........I'm hoping this thread to explain clearly how it all works, not perpetuate some mystery about how leds magically short circuit if you put a voltage that is not 100% exactly their ideal forward voltage on them...
I think that a datasheet like this one datasheet (there are plenty of them) gives you all the answers you need. You might want to have a close look at the curves, especially the "Fwd Current vs Fwd Voltage" one .