XM-L2

5 posts / 0 new
Last post
Firelight2
Firelight2's picture
Offline
Last seen: 5 hours 14 min ago
Joined: 04/08/2011 - 15:17
Posts: 4978
Location: California
XM-L2

Tried my hand at reflowing for the first time with an XM-L2 U2 emitter on a 16mm board. Not sure if I did it right, but it seems to work fine so I guess it’s good enough. (I put a 60w soldering iron point up in a vise, then used long-nosed pliers with cloth tape wrapped around the tips to hold the star while I held its bottom to the iron. I was waiting for the soldering paste to turn silver. That didn’t happen, but it did get hard and the emitter seems secure and hasn’t fallen off yet)

I put the new star into my modded SK58 zoomie with 2.8 amp driver on IMR 14500 and then placed it side-by-side with a different modded SK58 with the same driver that still had the older XM-L U2 emitter. At full zoom, I was able to see a clear picture of each die. My observations:

1. The stock XM-L emitter has the customary square die shape with 3 cut-outs for the wires. Visible dark lines in a series of stacked rectangles cover the top of the emitter.

2. The XM-L2 emitter’s surface looks different. When powered up there are 2 cutouts at the side for the wires. There is no third wire, however there was a slightly darker patch roughly corresponding to where the middle wire is on the XM-L. The top of the XM-L2 die has no visible lines at all. However, there is a grid of very small dark dots not present on the XM-L. These dark dots are much smaller than the lines on the XM-L.

3. The light output from the XM-L2 is remarkably uniform across the entire surface of the die. Much less variance than the XM-L.

4. Very unscientific, But looking at the die images side-by-side, it did seem to me that the XM-L2 really does look around 20% brighter.

Edited by: Firelight2 on 01/17/2013 - 14:07
totilde
totilde's picture
Offline
Last seen: 2 months 2 weeks ago
Joined: 12/27/2012 - 12:22
Posts: 1157
Location: spain

can you take two beamshots with the same exposure?

Mooooooo

nikanon
Offline
Last seen: 6 years 8 months ago
Joined: 08/25/2012 - 08:50
Posts: 439

Another member reported that

MattSPL wrote:

EDIT: Sorry, bad explanation. If you see in the pic i posted above, the little dot in the corner of the Led is on the positive side of the pcb, but it should be on the negative side.

Can you confirm that observation ?

Firelight2
Firelight2's picture
Offline
Last seen: 5 hours 14 min ago
Joined: 04/08/2011 - 15:17
Posts: 4978
Location: California

Confirmed.

Last night I reflowed an XM-L2 onto an XM-L star both from Illumination supply. I made sure that the small dot in the corner of the emitter was on the negative side of the star. It worked perfectly.

nikanon
Offline
Last seen: 6 years 8 months ago
Joined: 08/25/2012 - 08:50
Posts: 439

Thank you very much, now I can start to reflow solder a XM-L2 myself.