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ArcticMyst Security by Avery

Probs with 1st Build

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May 15, 2010
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I have. the driver tested around 1.56, didn't test the voltage under load tho :thinking:
 
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Blord

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What diodes are you using ? 405nm, 445nm M140 A140 ?
It can't be the batteries because the Moh driver will regulate the current with two 3.7V batteries.

The M140 445nm diode are a little more efficient than the older A140 445nm diodes. It need less current for the same output. I don't know if 1.6A is too much for M140.
 
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Yeah 1.6A should be just fine for any of the X140 diodes. Check the voltage across the diode when under load (when it is dimly lit). Chances are it's just not enough to cover the Vf.

I'm not familiar with Moh's driver, is it linear? LDO? Boost/Buck? Unless it is boost/buck or boost, or a very low drop LDO you'll likely have problems meeting the Vf with 7.4V. I think the VF gets up to 6V on some of those diodes.
 

Blord

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It works for that particular build. Maybe it was a rigid diode.
It doesn't mean every M140 is doing 1.6A fine.

Set the driver a little lower. Leave one 1R00 resistor. The current will be 1.25A but at least the survival rate of the diode should go up.

Moh driver uses LM1117 as regulator. It is a lineair driver.
 
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I'll give it a go tonight, try n carefully de solder on of the 1r00 resisters off !!

I can't have another rigid diode could I ???
 
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It works for that particular build. Maybe it was a rigid diode.
It doesn't mean every M140 is doing 1.6A fine.

Set the driver a little lower. Leave one 1R00 resistor. The current will be 1.25A but at least the survival rate of the diode should go up.

Moh driver uses LM1117 as regulator. It is a lineair driver.

the driver uses a LD1085 regulator for outputs of >1.25A
the manufacturers rates it as 3A max with a max voltage drop of 1.5v at 3A

for the lower powered drivers i use the lm1117

If you're getting 1.56A with your dummy load set to the correct setting, then it must be the diode.
At the same time, i find it hard to believe you could have gotten 2 bad diodes in a row, as they are pretty rare to begin with AFAIK which leaves me stumped on what is causing the problem.
I just hope it's not my driver killing your diodes somehow.

the flashing does sound like the driver is overheating though.
I usually use a 1/8" flat aluminum block arctic silvered to the driver's.
I keep a giant sheet of it and cut off pieces as i need them, and they seem to do the trick.
 
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I've no idea whats happening, I've built a few Reds and 405's now and had no probs, it's just these 445's I seem to be having probs with :thinking:

The coin thing didn't appear to work :( I've heatsinked it to the main heatsink, on the bottom, it juuust fits !!! (doesn't touch the sides at all)
 
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I am running an M140 with Moh's driver at 1.62A without problems.

Glenn
 
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Moh, has anyone had any problems using the case pin to feed the batt -ve ??

I may order a lower powered driver 1.2A or something .... Maybe ?
 
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shouldn't. The negative input and output on the driver is continuous. It's just on the driver for looks, it serves no purpose.
 
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I'm using a Guidsman host, the heatsinks on them are quite big !!! I've give up on it for now, not been feeling to healthy, got some sort of virus or something :(
 




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