Would 530mA kill the LPC836?

[adambowker]

Hi,

I posted a while back about dropping my LPC826 build (C6 host with 530mA driver). When I dropped it, the diode got extremely dim, and I assumed I broke it upon impact.

I got a new LPC836 today, so I wired it up and starting using it. It worked for a grand total of probably 35 seconds (10 seconds on, 20 off, then maybe 20 on, then a few hours off, then 5 on). The reason that last one is only 5 seconds on is because it stopped working after that. I'm not sure what an LED'd diode looks like, but mine is now really dim flickers a lot.

I tried new batteries and tried bypassing the tailcap switch but nothing would make it work.

The first time it broke (an LPC826), Jmillerdoc suggested the current probably killed the diode. I figured that was a little bit of the problem, but I really thought I just broke the diode due to impact. He suggested getting the LPC836 as a replacement rather than another LPC826 since it could better handle my 530mA.

This time when it broke (an LPC836), I didn't drop it or anything - it just went dim while I was using it. That leads me to believe that the current killed it. However, reading other threads, it doesn't look like 530mA should have killed it.

What are everyone's thoughts? Did the 530mA kill the diodes, or was it something else? There really isn't anything else I can think of, but I don't know everything.

I'm mainly asking so I know how to fix it for good. I don't want to buy another diode and kill it with the current, and I don't want to buy another driver if that's not the problem. I just don't know what to do

Thanks in advance everyone!
-Adam :yh:

 

[Flaminpyro]

Yep it's dead, while some LPC diodes may be able to take that much I don't believe they all can and yours just proved that.

if you have a test load or a 445 diode you can check to see that the driver is still operating correctly but my money is on a dead LPC.

 

[adambowker]

Thanks for your input man.

I don't have a test load yet. I do have an M140 diode but it's not wired up yet and it's stuck in a heatsink (can't find my Alan wrench lol) so I can't use it to test just yet. However, I don't think the driver is dead either since it worked for the first few minutes in both of my builds. But again I don't know enough about this stuff to make a solid conclusion.

I just emailed the supplier of my 530mA driver to see if I can get it switched out for a 445mA... if he can't switch it out, do you (or anyone else reading this) want to trade? If current is the problem, then 445mA should work better - right? I just don't want to spend another $20 for a driver and then have one I'm not using.

 

[grainde]

Yup as FP said it sounds like the current was too much. Ive got a couple of 650's extracted from sleds and as I wasnt sure what they were I ran them at 350 / 380 mA. If you wanted to try 380 mA for a longer life use a single AMC 7135 chip. You can pick up a cheap driver $ 3 - $ 4 from FT/KD/DX and should get around 250 - 300 mW. Alternatively you could buy the chips for under a dollar and build your own. Good luck :beer: