It's a boost circuit.
Seems to be regulating at about 700mA.
Poster above is wrong; should be about 2w and 200 lumens. Also the efficiency is probably closer to 80%+.
Nice find, it would be pretty decent with a LED swap.
I really don't think you should build your own circuit if you are not an electrical engineer. Even if you are most would probably opt to use premade circuits.
See my post above on a simple solution that will leave you satisfied with the amount of DIY work that you'll be doing.
I don't see you designing a circuit that works all that well.
I'd say the easiest and best way is to buy 3 Buck circuits, and use 4 batteries in series.
Then pwm the three using an arduino with 4 pots in the adc to set the pwm level, or cycle through some preprogrammed levels.
Look for voltage specs for figuring out how many are in series.
Then you can divide and get one or two good guesses for how many in parallel, as you said, for example ~2000mAh is fairly common for many older laptops.
Some newer nicer laptops can potentially have ~3000+ mAh batteries; but those...
I've heard the high cri xpg2s are quite nice as well, but it sounded like they weren't nearly as nice as the old Nichia 219b. I hope that someone with experience with both can provide some opinions as well.
particularly I'm worried about color consistency on the edges, which seemed...
Yesterday I stumble upon a driver I had previously bought in preparation for a desklamp, but I had forgotten to build it (that was close to 4 years ago)!
Originally, I wanted to use a triple Nichia 219B 92CRI 4500k setup, because IMO it's an awesome high CRI tint.
However, now that it's...