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ArcticMyst Security by Avery

PHR805T current help?

Joined
Nov 20, 2012
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So I keep reading and reading and searching and searching. I can't find the thread now but it something about 'LED'ing his PHR805T at 200mA. I have been running mine at 375mA originally set for my LPC815 (that of which I led'ed :() but forgot to pull the resistors from the LM317 setup, with short cycles seeing as how I'm still in the process of deciding what kind of host, driver, and heatsink I want to put all into. [I actually just got into the hobby ^_^ after being a laser enthusiast since my childhood days.]

BUT back to the reason I posted this. I'm curious as to why my diode hasn't LED'd yet. Did I get something other than a phr805t?
 





Joined
Jun 7, 2012
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Two laser diodes, even of the same kind and from the same manfacurer, can have very different qualities. Their efficiency and durabilities can vary quite a bit and it's just part of the hobby, the diode data sheets from suppliers give typical ranges or operation rather than specific values.

You diode might be more resilient to higher currents, but even if that is the case 405's diodes do degrade much quicker than 445's, just because you can run a certian level of current through it today doesn't mean it can handle the same current a month from now.
 
Joined
Dec 23, 2008
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375ma for a PHR is triple the current. PHR's should never be set over 120ma.

Michael.
 
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Feb 1, 2008
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150mA was sort of popular for those who liked to push their luck, but PHRs have been <$20 for a very long time now. ;)
 
Last edited:
Joined
Nov 20, 2012
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I'm running 9 volts on the lm317 linear.

And thanks for the replies, gives me a better idea of what I should and shouldn't be doing. xP
 
Joined
Dec 23, 2008
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Where is your 9 volts coming from? The typical 9v square batts are considered junk around here. They don't provide enough current.


Michael
 
Joined
Nov 20, 2012
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6 double AAs. And out of curiosity, I have read 9 volt squares are garbage, but why exactly? Low mAh? Or what is it exactly?
 
Joined
Dec 23, 2008
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Exactly, low mAh. They rated at like between 50-100. Back in the day they were ok for all the low powered lasers, but not any more.


Michael.
 
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9V batteries are simply a "battery" of 6 AAAA cells connected in series. If you've seen a AAAA cell before, you'll know its even smaller than a AAA. So yeah, not good for more demanding current loads.
 




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