Cheap way to light ONE LED??

[sfsuphysics]

I'm not talking a 5mm LED either. I have a setup of 4 RB and 1 CW, however I want them powered separately so I can turn the white off separately. I can get the 700mA meanwells for ~$16 or so, so I doubt I could go lower than $4 per LED with the RBs, but the CW one is busting my chops. A meanwell won't do just 1, I know I could go the direction of a buckpuck but that's just as expensive (if not more) than the meanwell. Short of using a wall wart with resistors to make sure the current stays within range (I'd rather not waste power via resistors too) are there any options?

 

[austin93]

Might look at rapid led. They have a driver for moonlights that lights 3 I believe.

 

[Rybren]

How about one of these?

http://www.dealextreme.com/p/waterproof-650ma-3w-led-constant-current-source-power-supply-driver-85-265v-81772

Shipping to Canada from these guys has slowed down considerably as of late. Don't know what it's like to the US. I'm runnning a couple of their 9W drivers on my pico tank. So far, they've been quite reliable.

 

[Curve]

The rapid led moonlight kit will do 1 to 3 leds

 

[skunkmere]

i used these for my 4 3w royal blue moonlights.
http://www.dealextreme.com/p/700ma-3w-power-constant-current-source-led-driver-100-240v-66329

 

[kcress]

"Waste a bunch of power"? Just use a 5V Wallwart and a resistor. Go ahead waste a single watt. It's ok.

 

[sfsuphysics]

"Waste a bunch of power"? Just use a 5V Wallwart and a resistor. Go ahead waste a single watt. It's ok.

Relatively speaking

Besides my mindset was thinking of all the 12V wall warts I have lying around, and the resistors I'd need to step down that.


Thanks for the dealextreme links, I might go that direction, although if it's like $5 to ship, it leaves the realm of cheap. Wallwart might be my choice if I can find one laying around that's appropriate voltage.

 

[der_wille_zur_macht]

Wall wart and resistor. Be sure to size the resistor experimentally in your actual steady-state operating conditions, or use an adjustable one.

You could also spend about $1.50 at Radio Shack and build a constant current reg with an LM317 that would essentially be the same efficiency as a resistor but would "self adjust" so you wouldn't have to tune it.

 

[Rybren]

although if it's like $5 to ship

DealExtreme is free shipping on the drivers.