What went wrong?

Poor diode :cryyy:

I think both of us need to start being more conservative with our diodes... My LPC-815 and your LPC-826 both died after 2 months.

could it of been a heating issue?

mine wasnt thermally glued to the module or heatsink of the hotlight, maybe that had something to do with it?

gunna replace it with a copper module and some thermal glue and see what happens!

^^^ I dont think thats the case. It happens. Ive Lost LD too. LPC-815 the most. The Life of a Diode is Pretty Unpredictable. You can have one of the best most efficient diodes out there and it lasts shorter then any other diode out there. But it is a possibility that OP problem was Caused by Heat..

Your Hotlight heatsink without thermal paste is more then enough for a LPC-826.


The Op said he soldered his diode to the Driver. he Might of forgotten to short the leads to discharge the caps on the driver before connection to his diode.

Maybe he used to much heat when soldering the diode to the driver. He could have also gotten a Dud LD or Laser Driver. However i know Survival Lasers test each driver before shipping but there is still a chance that something can happen afterwords. But this Driver was Bought second hand so Unsure.

OP. A quick and Easy way to find out if your driver is not working properly is test it with a Testload. This should tell you if you have a Bad Driver.

Do you have a testload.?

I don't have a test load, I was going to build one today, but stuff came up. Hopefully tomorrow. I was going to go off this diagram, is this correct for my purposes?

Mine was running nice and really cold ( because it was cold outside last weekend+ a overkill heatsink the Aixiz never evebn got warmer then 20.C and suddenly pop and it was LED that all @ 480 mA 3 V

I received and tested this driver, it still measured 515mA on my test load at the two diode setting with a single 18650 battery, and no squealing or other noises could be heard. Sounds like there might have been something wrong with the diode, or another problem. I personally found two DOA BDR diodes out of 24, so it happens.

Let me know via PM or forum reply what you'd like me to do with the driver.

Alright guys, driver went out to survival lasers, tested, was working fine there, sent it back to me, great service, thanks again. Got a new diode in. Found a problem with my battery charger... not sure if that was at all related, but got a new charger. Put it all together with freshly charged batteries. It all seems to be working, so I am guessing it was a bad diode?

The only thing is, I still get that squeal for just a half a second everytime I turn the laser on... makes me a little nervous, not sure if it's normal or anything to worry about, so I haven't kept it turned on for more than a few seconds. Any thoughts on the noise? It sounds like an old school camera when it's charging the flash, but much much quieter. Thanks for any thoughts.

What Battery do you have and are using.?

Noise seems to have stopped after charging the battery again, maybe I'm just going crazy. Used the laser quite a bit today, kept it on for pretty long. I'd say it's working properly.


Battery is an ultrafire 3.7v 3800mah 18650

^^^ There is No Such thing as a 3800 18650 cells.

Im Guessing you are using a GTL Cell or one of those Black and Gold UltraFire cells from Ebay.

Thats your problem. Get a Better quality cell that holds a Charge better nd that can take the currant.

I recommend some Sanyos from LaryDFW on the Forum. Do a Search and they will come up.

I seem to remember that some drivers may produce noise if the voltage gets too low. Lazeerer, can you confirm this?

lazeerer said:

^^^ There is No Such thing as a 3800 18650 cells.

Im Guessing you are using a GTL Cell or one of those Black and Gold UltraFire cells from Ebay.

Thats your problem. Get a Better quality cell that holds a Charge better nd that can take the currant.

I recommend some Sanyos from LaryDFW on the Forum. Do a Search and they will come up.

Click to expand...

Ill second that, my "Ultrafail 4000mAh's" use to make my flexdrive inductions whine really bad, and the output power was unstable too.

Ok, this is good. This is the first time I used 18650s, didn't really know what I was looking for.



These are what I was using. I'll look into some new ones. Any links to where I might find these better sanyo batteries? I find a lot of results but the battery shown is a completely unmarked/unlabled red/orange guy, just making sure that's what I'm looking for.