Outer Limits 4x4 Board

Hey all, i am trying to drive a 3w white luxeon led from a hot beam electronic driver (25w), but it it only flashes the led/s.

I have tried a few things, ie heatsinks, tested the driver on a led rope light

Anyone got any experience with the luxeons?

personally not really, Have mucked around with 1watters though, but not with specific current limiting drivers. My only suggestion to get it working as quick as possible is to fork out dollars for a jaycar or oatley electronics driver kit. ~$10 to $20. www.oatleyelectronics.com.au if you dont know about them. Have good stuff. Other than that, no idea. Do a dodgy and work out required resistance value for required voltage supply. Not real efficient and not real crash hot.

I have no idea what you are talking about...
http://www.luxeonstar.com/resistor-calculator.php
hope this helps tho'.

want33s wrote:I have no idea what you are talking about...
http://www.luxeonstar.com/resistor-calculator.php
hope this helps tho'.

That does the calculations for bushy's "dodgy resistance value" method. Effectively, that's creating a simple voltage divider, which also divides the power delivered from the voltage source. For example, if the Luxeon has a 4V forward voltage drop for its 3W output then the resistor(s) are dropping 8V and throwing away 6W (presuming a 12V source.)

A decent driver kit uses switchmode technology to avoid wasting all that power. Why bother?

In the real world, I think a 3W Luxeon drops less than 4V (OK, I'm probably way out) and a 12V battery will deliver more than 12V - so a simple resistor divider could be wasting more than 2/3 of available power. This means a driver with a real world efficiency of 80-90% can get close to 3 times the run-time out of a given "amount" of battery charge.

Alternatively, you could consider that the fancy driver leaves more power in the battery for keeping the fridge cold.

Thanks for the input, the driver i am using is a 240v input which i am bench testing before buying a jaycar 12v driver.

I am thinking i am not proving much by this and should just buy the 12v driver.

For interest sake the autospeed website has a good article on converting a mobile phone charger to a luxeon driver, it's pretty straight forward - but once again i think i will just buy the jaycar one.

These luxeons are freakin bright, jaycar sell a generic brand for a lot cheaper which i will be trying next.

thanks again
mark

http://www.kaidomain.com/WEBUI/ProductD ... ranID=2982

these drivers are great. and can run LED's in series.

remember that Luxeons [or Seuols or Cree's] need to have a heatsink on them or they will burnout.

check out candlepowerforums.com for more LED related info.

G

save you the effort

http://www.candlepowerforums.com/vb/