USB and flashlights

what USB-powered or USB-rechargeable choices are out there?

I found a link to a USB-powered battery charger , and another site that went into some detail about battery charging by USB.

is someone making a USB charged flashlight? might be nice to have at work, or travelling. if you could plug right into the light, the need to drag a battery charger around could be eliminated.

might be nice to do sneaky recharges at work /ubbthreads/images/graemlins/grin.gif

Heres a new light that was just reviewed /ubbthreads/images/graemlins/smile.gif

http://www.candlepowerforums.com/ubbthreads/showflat.php?Cat=&Number=799218&page=0&view=collapsed&sb=5&o=&fpart=1

yup, thanks. that's what prompted me to start this thread.

really thinking of something in a more standard style. /ubbthreads/images/graemlins/smile.gif

watt4,

heh, yea, I had an idea thats what got your head spinning with USB thoughts

If someone could post here, what the specs are for USB ports, we could always made/mod lights to suit that.
I know there have been chargers for LiION cells made that run off USB. /ubbthreads/images/graemlins/smile.gif I have one comming to me actually.

sounds like a slow way to recharge batteries

jtice, 5V, and 500mA maximum per USB root hub. Usually, one root hub powers a group of two ports that are placed on top of each other or side by side. If one device uses all 500mA the other device must be self-powered.

I have this AA USB charger that has worked quite well, it's a dumb 300mA constant-current charger but I used it to handle my AAs for a year and a half. Saves fishing for the wallwart.

Older Nokia phones used to have this third-party USB charger - just a plain cable with two appropriate plugs that would allow you to charge your phone from the USB port. Excellent little device which I used a lot, until Nokia nerfed it by deliberately making their phones watch for 5.2V and flash "Not charging" when connected to the USB connector. Only their 5.2-5.3V wallwarts would do. *sigh*

Just the other day, someone was telling me that their Samsung phone even had a USB charger cable supplied with it.. (I live in the land of phone freaks /ubbthreads/images/graemlins/grin.gif)

So it is possible, definitely. A full charge of two AA cells and even four (like my charger) may take a few hours, but it's do-able. Trickle charging should be no problem as well. A charge-in-place light would rock /ubbthreads/images/graemlins/smile.gif and since my work keeps me near a computer most of the time it would definitely be of interest to me.

4 AA cells go a long way - think WA 1318 hotwire for ridiculous light (and very short runtime /ubbthreads/images/graemlins/grin.gif) or Luxeon V for maximum LED output.. or Lux3 for something a little more practical with better run /ubbthreads/images/graemlins/smile.gif

Hey, watt4 -
Here is a thread by djpark about a homemade USB charger for Li-Ion Cells. His cells were AA size IIRC. Alot of other electonically-minded boardmembers chimed in with input, too. Lot's o' good info on it. It's in the 'Flashlight Electronics - Batteries Included' Section.
Hope this helps!

Danno

Ah thanks Kevin, I didnt think it was that mcuh power, thats certainly a usable amount for many aplications!

I have a sound-activated light that runs on USB. It has 5mm green LEDs at the ends of a plastic diffuser tube, which works pretty well as a light bar. It has a constant-on mode, so it can sort of be used as an area light.

It's actually pretty useless, but it's fun to turn off the lights, turn up the volume, and play Counter-Strike.

If someone comes up with a serious charge-in-place USB light I'd definitely be interested.

I have some ideas about a cradle-mounted light but lack the expertise to build it, especially the problem of building the contacts into the light. Either that, or a cable mounted light, but then the charger electronics would have to be inside the light. For a removable-battery-pack light, I could stick to any AA light plus my AA USB charger.