Cree emitter flickering

[van1]

Do Crees need break in time? Has anyone experienced them flickering when they are brand new and just installed in a 600ma application?
thanks

 

[Nitroz]

I have never had any of the Cree LEDs flicker.

Can you give some more details to what you have it installed in?

 

[van1]

Installed on a Minipro. Have built up 3 of them at various times and all have done it. Kevin has been great about selling me the 1st replacement parts at a discount. But I eventually sent him the emitter AAd to the heatsink and he built a Minipro and installed it on the heatsink with the Cree on it and even HIS started to flicker. One of his opinions was that the Cree wasn't isolated and was shorting out the pill. (corners were all cut off the Cree so it would fit onto the heatsink, and continiuty tested to insure that the top and bottom contacts no longer were connected.) So not sure if it's the Crees thats causing this or somthing in the Minipro.

thanks,

 

[greenLED]

if it's not a cold solder spot, it sounds like the inductor saturating. Could you describe this "flickering", please? Is it pulsing or rather random?

 

[Nitroz]

Have you tried a regular luxeon LED on the minipro?

Have you powered it outside of a flashlght?

 

[greenLED]

Nitroz is right on - it could be a host problem...dirty internal contacts, threads, a shorting "lip" somewhere...

 

[van1]

Totally random flickering. I think I've figured it out though. i've applied artic alumina around the heatsink to get the heat away from the electonics. since the Minipro heatsink completely surrounds (encases) the board the heat is going back to the board. With the AA applied seems like the flickering is gone for now? Not sure if this is the fix, but seems to be working.
FYI. I have tried it outside a host, with a diffent emitter (lux, and K2) etc, and it has always started to flicker after a few minutes runtime.
I am going to get my temp gun from work tomorrow and check out the beofre and after temp.
Thanks,

 

[2xTrinity]

Could be a loose connection that is being affected by thermal expansion -- I've had lights that work fine cold, then once they get warmed up, go off without warning as the thermal expansion in the wires severs a connection that was just barely there to begin with.

 

[p97z]

Does it do it with a newly charged battery? Could be the electronics overheating because the voltage is higher then expected...

 

[Nitroz]

Totally random flickering. I think I've figured it out though. i've applied artic alumina around the heatsink to get the heat away from the electonics. since the Minipro heatsink completely surrounds (encases) the board the heat is going back to the board. With the AA applied seems like the flickering is gone for now? Not sure if this is the fix, but seems to be working.
FYI. I have tried it outside a host, with a diffent emitter (lux, and K2) etc, and it has always started to flicker after a few minutes runtime.
I am going to get my temp gun from work tomorrow and check out the beofre and after temp.
Thanks,

Maybe applying the AA isolated a short that was occurring to the heatsink. This would explain the reason it happens outside the flashlight also.