Hey, I’m playing with some joule thief circuits, and I’m wondering what is the lowest power consuming LED?
I have used the Vishay low current 3mm type (TLLR4400) for indicators before and could be a possible candidate?
Just be aware that an LED will consume whatever power your joule thief will provide. Even a high-power LED like an XM-L will provide at very low currents.
So I'd say, if you just want something that lights up in your setup, use whatever you have on hand :)