C6 power problem, power dropping..

So as the title says, i'm building a laser in a C6 host..
Not sure what the diode is it may be an M140 or A140, but i don't think that maters, got it from a member on the forum and it was already pressed in a module, he also did not know what it was.. That's why i'm running the diode at 1.25A..
I'm also using a 1.25A Buck driver from survival laser.
And for batteries i'm use two IMR 16340's

So the problem is that when i turn the laser on, its bright for around 500ms then it get dim, like super dim i would say sub 100mw, so very dim..
I don't think its the batteries because i tested them, and they are at 4.2v, also i got them off of Livinloud a week ago..
Also just having the pill in the host i tested the driver with my test load and i got 1.25A..
And for the diode, i just had it tested by a friend on the forum and he told me it was fine..
The diode also looks fine for the 500ms its bright..


What is my problem??:wtf:


:beer:
Rich

Bump..

Welll, its certainly not a diode problem, so thats good at least. My guess is driver problem, but im certainly no expert- however, and thankfully so, there are plenty of experts here

Update..

Its not the batteries. I tested the driver and diode with a power supply set to 8.4v, i got the same result of the power just dropping..
Next i desolderd the driver from the diode, and hooked it back up to my 3A test load, and i got 1.25A?!?!?!?!? Then i hooked it back up, and i got the same power dropping affect...

:wtf:

Not sure what to do:yabbem:

Do you have an 18650 battery? If you do then take out those 16340's and put in the one 18650 and see if you get the same result.

It sounds like your driver circuit is overheating. This creates resistance I think? Causing the current to drop. I had a similar issue with a 532nm module I had once. Try heatsinking the driver.

Is this the driver? Survival Laser Driver
If so then it is very efficient and should never overheat or require heat sinking.

Pi R Squared said:

Is this the driver? Survival Laser Driver
If so then it is very efficient and should never overheat or require heat sinking.

Click to expand...

Yep that's the driver i got..

With an 18650 i get the same dropping affect, just not as bright when it first turns on..

Also i was noticing that when the laser sits for a long time, and when i turn it on it will stay bright for around 2.5 seconds, then goes dim.. Then after that first 2.5s, every time i turn it on after that it will only be bright for around 500ms..
So maybe its a heat problem??

Should i just ask for a new driver??

I had this same problem a while back with an M140 laser diode. It turned out to be the diode. No kidding. I was driving it with lazeerer's 1.8 amp V6 X-Drive and the laser would be fine for a short while, then it looked like it's laser cavity got destroyed and it turned into an LED. It finally went to LED "mode" all the time, and that's when I replaced the diode. Problem resolved.

P.S. Also, since this is a buck driver, you can't just substitute an 18650 for two 16340s because your input voltage will be too low to drive the diode.

Just tested the amps going form the driver to the diode.. It was a steady 1.25A I guess that means it's the diode.

P,S, Thank you all, for helping me diagnose the problem.
I only wish the outcome would of resulted in a bad driver, and not a diode..

i73770k, sorry to hear that, but I'm not surprised. It really sucks when you lose a $45.00 diode in such a short time of use.