KevinL
Flashlight Enthusiast
I finally built my triple XM-L mod 
It went quite smoothly except for one issue: the light is insanely wicked crazy awesome bright, but I suspect the driver is going into thermal overload and automatically throttling power. What happens is that after a while, the current draw at the tailcap starts rapidly dropping back to 1 amp in steps (not all at one go). I'm using one of the AMC 2.8A drivers from Shiningbeam wired in Download's 3 x P7 topology (http://www.candlepowerforums.com/vb/...d.php?t=168062 - 2nd last pic from bottom of first post). Or click here for the topology.
I could be wrong though, feel free to suggest a different cause.
The drivers are wired this way:
The wierd thing though, is that my P60 modules 2.8A P7 or XML modules based on the same driver do not have thermal management problems despite the fact I did not do thermal potting or sink them to the sides of the module. Perhaps because I am essentially running 12V+ thru this circuit instead of 4V?
How would I narrow down the cause of this problem, and how would I heatsink the drivers if necessary? I see chips on both sides and I can't for the life of me figure out how I would craft a thermal pathway for it.
The heatsink of the light itself is doing great, never exceeds 38C (because of the throttling though).
Also, I need some nice optics for the XM-L.... I got the Carclo optics but they are so-so and the beam pattern isn't the nicest it could be.
It went quite smoothly except for one issue: the light is insanely wicked crazy awesome bright, but I suspect the driver is going into thermal overload and automatically throttling power. What happens is that after a while, the current draw at the tailcap starts rapidly dropping back to 1 amp in steps (not all at one go). I'm using one of the AMC 2.8A drivers from Shiningbeam wired in Download's 3 x P7 topology (http://www.candlepowerforums.com/vb/...d.php?t=168062 - 2nd last pic from bottom of first post). Or click here for the topology.
I could be wrong though, feel free to suggest a different cause.
The drivers are wired this way:
The wierd thing though, is that my P60 modules 2.8A P7 or XML modules based on the same driver do not have thermal management problems despite the fact I did not do thermal potting or sink them to the sides of the module. Perhaps because I am essentially running 12V+ thru this circuit instead of 4V?
How would I narrow down the cause of this problem, and how would I heatsink the drivers if necessary? I see chips on both sides and I can't for the life of me figure out how I would craft a thermal pathway for it.
The heatsink of the light itself is doing great, never exceeds 38C (because of the throttling though).
Also, I need some nice optics for the XM-L.... I got the Carclo optics but they are so-so and the beam pattern isn't the nicest it could be.
