20K MCD LED from ebay is strobing?

I got some 20k MCD LEDs off ebay and recently its stared "strobing" like a disco when its on. is it dead?

I tried another LED off the same batteries and it didnt happen. this is the first time I've ever seen it happen.

is this a normal occurance? /ubbthreads/images/graemlins/confused.gif

Occasionally one runs into them, one possible explanation is that inside the LED, one of the contacts is intermittent. When powered up, the metal inside expands, breaking the contact, and cutting off power. The metal then cools off, contracts, and makes contact again.

Very cool, but they won't last long. I had one keychain light like that, it so happened it was the first one I kept for myself. It was OK for the first few days and then started strobing. What are the odds.. /ubbthreads/images/graemlins/smile.gif

Strobing is one of the failure modes of LEDs subjected to current spikes. When I used to repair LCD taximeters which used LED backlights I saw this all the time.

I have a few that are strobing. I think mine were possibly damaged by excessive heat when I soldered them followed by overdriving them to about 40ma average, perhaps 50ma.