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ArcticMyst Security by Avery

Current Regulator

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May 7, 2008
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So ive been having some issues with my blu-ray build. I cant seem to get the current and the voltage i need to get the xbox 803 diode to light up safely. with my driver (that ive built, LM317 included) i always seem to get far to much mA and not enough voltage. there must be a way to wire up the LM317 to regulate current right? I can get my diodes to light up, but its usually under the circumstances of pumping far to much current through them with inefficient voltage.
 





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If you have followed the default build for the LM317, it is then in current regulating mode, and you would be able to adjust the current from there.
 
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What batteries are you using? also, How much current did you end up sending through it? You may have killed it.

with the lm317, the diode will take as much voltage as it needs to power at the set current level. So if you set the current to 90mA, the voltage will sort itself out as long as you have enough voltage to begin with (usually between 7.5 and 9v for the blu-ray with lm317 driver. The diode itself needs just under 5v)
 
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That may be my problem then... I am only using 4AAA so 6V. I am using a series of four 15ohm resistors to simulate the diode, thats appropriate correct? Ill take a crack at it tonight, with more voltage.


Is there a different chip other than the LM317 that i can use that will allow me to work with less input voltage? I couldnt find one that would work at radio shack.
 

chido

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6v is the minimum voltage for the LM317, but you're going to want to put in more than that, otherwise, as soon as the voltage gets below 6v the driver won't be able to provide the diode with the power it needs.
Get this, you can power it off 3v if you want to.
 
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i have 2 of those, but they're expensive, and im making this one into a box style pointer so i didnt have size requirements.

Thanks for the suggestion though. :)
 




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