Circuit/Battery combos for driving a single 5mm LED
January 18, 2011 9:10 AM Subscribe
I'd like to use a single 5mm UV LED (3.4Vf, 20-25mA)
to charge a daub of glow-in-the-dark paint. It only needs to be lit around 1 minute of every 10 (or 6 seconds of every 60), and only when the (room) lights are out. What battery/circuit would be most economical to operate, and require the least-frequent battery changes?
posted by jjjjjjjijjjjjjj to technology (6 answers total)
I'm not a circuit-design wiz, but I can RTFM and I can follow directions. I breadboarded someone else's design
using an LM555, but it sucked down batteries (and was probably imperfectly implemented on my part).
What battery would be best for long-life (3 large 1.5V cells? a single specialty 4.5V cell?), and what circuit would maximize this? Realistically, what's an order-of-magnatude estimate of the type of battery life I could expect? 1 month? 6 months? More? Less?
The project allows a lot of wiggle room, and if there is a "sweet spot" to be found by taking it into a direction I've not anticipated, I'm all ears. I can answer any questions about anything I've left unclear. Many thanks.
Also: any suggestions of other online communities that frequently discuss things like this?