I have an idea to upgrade an all-purpose general around the house use light with one of these emitter boards with (1) AMC7135 on it and an XM-L emitter (I'm looking for pretty much max output at that 350mA level and mostly flood. The board looks odd to me; will an XM-L mount on one of these?
I know this is heresy not to mod a light for huge output, but I am looking for runtime and the ability for it to run on alkalines. Please don't judge me! :) Oh, and I have very little room for heatsinking, so I am guessing an XM-L at 350mA requires extremely little heatsinking, right?
That board is designed for LEDs with the little +ve and -ve legs such as the older Seoul P4 or Luxeon LEDs. Even if it was designed for an XML, at 1W, A 20mm star alone would get pretty hot. (not sure how hot though but I’m sure if you put your tongue on it, you wouldn’t like it lol )
Well you can’t reflow an XML to that board. That looks like it is for a seoul emitter.
Also, if you want to run it off alkalines, you need at least two of them in series with a linear regulator.
With the dropout of the AMC7135, you probably won’t even get the 350mA from two alkalines, at least not for very long,
so you’d need 3 in series.
Regarding heat: 350mA through a led equals roughly 1W of heat (in the emitter). If you run that board with 3 alkalines (4.5V), then the 7135 will also generate some heat, about 0.5W. Without any heatsink this might get quite warm after a while, but you shouldn’t need too much of a heatsink.
That's what I thought. I guess there is no option for a similar board for Cree emitters.
This light uses 4 AA's in series, although I could mod it to 3AA if I needed to lower voltage.
Exactly my idea, but I was planning this for my 8 year old daughter to use in her room or walking to her friends house. She tends to set lights down and leave them on.
i opened up an energizer 1W headlamp, removed the xp-c and put in an xm-l. the ‘heatsink’ has the mass of maybe 2 or 3 20mm stars, has no path to the ouside and is surrounded by plastic. the light works great.
Interesting, I was just going to ask a similar question. I’m modding a flashlight that was given to me, has an old lumileds star and emitter in it, pretty anemic output. Driven by 3 AAA’s. I was going to swap the star with one I got from sinkpad for an xml2 or xpg2, but was worried about the fairly bad heatsinking. The star fits inside a hollow collar that then screws into the body of the flashlight, so at least it will transfer some heat to the body. I was thinking of adding a small stick on heatsink from a computer memory kit to the pack of the sinkpad.
Hypothetically that should be extremely easy to make, once I have a WORKING XML library file I could probably make one of those for an XML. However that probably won't be for a while. :(
That's interesting. Seems a bit too warm for my taste and I don't see any other choice in that seller's Ebay store. Also, if they are 7135's, why is it 500mA output? Are they are lower bin of 7135's?
Thinking again, I guess I could use the board in the O.P. sort of like a "driver board" and just wire a standard XM-L on a star from that board. That would work, right? It could be perfect if that center pad is where my B+ contact could be made. Anyone know if that's B+ at the center?
No, center pad should be electrically neutral, at least in stock form. Look close and you can see the traces. If the center pad is also isolated from the backing, you could easily make it the B+ with a jumper wire.
