LED Repair Q + A

[zekeyou]

Torch brand: ALPIN (??)
Type: LED
Question: Cree led chip type Re battery voltage

Hi. I found a few days a go a led flashlight (tactical style) branded ALPIN. I know nothing more Re the model of the torch. The torch led is not working. Battery type on it at the moment are 2 x CR123a. I've removed the led chip and tested voltage on the two leeds. The total comes about 5.77V. Did not managed to measure the Amperes but I guess the CR123a have 1.5 AH. The aim so far was to check whether the led driver, which is underneath a small plaque which is locktite, so I suppose since I am getting power at the leads should be ok. As I need to get a cree led chip to replace my question concerns the Cree led wattage.
I am limited to ebay in the UK as I cannot find (online at least) and seller so I will go with the Chinese seller which unfortunately it will take long to arrive and I am really keen in attempting the repair.
Cree led chip types found:
- 5W Cree XPG which is 5W. It says 1A but in Cree specs I see the XLamp XPG being 1.5A
- 3W Cree XBD which is 3W and should be 1A.

So my question regards choosing the appropriate cree led chip. Could anyone give some advise Re how I should select the correct wattage?
Thanks alot.
K.

 

[peter yetman]

If you have 5.77v at the Led, it's the reason that the emitter burnt out, more than about 3.5v and they are dust.
Looks like your driver is dead.
Treat yourself to a new quality light. Or build one, good bits at 3Tronics.co.uk.
P

 

[zekeyou]

Thanks for the reply. I'll check the link out. I hope i can open where the driver is. Thanks again

 

[zekeyou]

Any idea how to unscrew this : see image
It seems locktited.

https://www.dropbox.com/s/6z57vneyufjwed9/.jpg?dl=0
https://www.dropbox.com/s/ctef6k357ewt5vd/.png?dl=0