[Noisebridge-discuss] driving multiple LEDs with minimal batteries

[Michael Shiloh]

It's Rolf, copied on this.

On 01/05/2011 11:49 AM, Jake wrote:
> There was a guy who came to Circuit Hacking Mondays who made these tiny
> circuitboards with a Linear Technologies chip that boosted power from a
> low voltage to up to 30 volts with a set current limit.  He brought them
> to CHM as a kit i think, and was making umbrellas with hanging lights.
>
> Mitch or Miloh will know who i'm speaking of.  He was really tall and thin
> and older than Miloh...
>
> anyway the great awesomeness of his kit is like this:  you hook up a
> battery to it (a single AA, rechargable or not) or a lithium-whatever, it
> doesn't care - and it will work.
>
> On the output side, you simply wire all your LEDs in series - one after
> another, any colors, no resistors necessary - and the thing will power
> them all with the same current.  Regardless of the state of the battery
> (until it is empty)  Up to 30v or 10-15 LEDs in series per board.
>
> I think the appropriate way to power a scarf is with a single AA sized
> battery.  People can use a disposable battery but a rechargable AA is
> ubiquitous and appropriate, and an be charged separately from the scarf.
> And a scarf is something that will hopefully outlast any LiFePo battery or
> NiMH cell, so it has to be a standard, replaceable cell like a AA.
>
> -jake
>
> ---- original mess ----
>
> I'd like to do a soft circuit scarf or three, but I'm always running up
> against the problem of power. I usually use fairly low power LEDs
> (<2v) driven by a 9v battery or one of sparkfun's LiPos.
> I've heard tell of somehow being able to power more, but I'm still
> learning
> this EE stuff. Could some kind person point me in the right direction?
> Meredith
>
> _______________________________________________
> Noisebridge-discuss mailing list
> Noisebridge-discuss at lists.noisebridge.net
> https://www.noisebridge.net/mailman/listinfo/noisebridge-discuss
>

-- 
Michael Shiloh
KA6RCQ
www.teachmetomake.com
teachmetomake.wordpress.com