i heard you can get an led driver out of an old computer

Discussion in 'General Electronics Chat' started by dvan, Mar 14, 2014.

  1. dvan

    Thread Starter Member

    Feb 8, 2014
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    is there any truth to this >]?:D
     
  2. Sensacell

    Well-Known Member

    Jun 19, 2012
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    Where are these LED's on the old computer?

    Most old computers I have seen have no LED's other than a few power and status indicators- none that would warrant a driver.
     
  3. dvan

    Thread Starter Member

    Feb 8, 2014
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    No its for a different led circuit.. Its a 10 watt led I'm getting. I'm asking if there is a driver in these old computers
     
  4. spinnaker

    AAC Fanatic!

    Oct 29, 2009
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    See above.

    Why would an old computer have a 10w led driver when it does not have 10w LEDs???????
     
  5. dvan

    Thread Starter Member

    Feb 8, 2014
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    Why would you waste my time if you don't know?
     
  6. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    I think he might be talking about the old PC PSU box, which can provide 12v DC and 5v DC.

    To Dvan; that is called a "DC power supply". Yes it can possibly be used to power a 12v 10W LED but may need some adaptation.

    Your best bet is to check ebay etc for "10W LED driver" and buy something that is exactly suited for your task. :)
     
  7. KJ6EAD

    Senior Member

    Apr 30, 2011
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    No. 10 characters
     
  8. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    You can use a 12V supply and a meanwell LDD-1000HW
    Assuming this 10W LED is a 9-10Vf @1000ma
     
  9. abhaymv

    Active Member

    Aug 6, 2011
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    Without the specs, you really can't tell. LEDs are current controlled devices, so I'd be weary about driving it with a voltage source.
     
  10. dvan

    Thread Starter Member

    Feb 8, 2014
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    the last led i had blew out it had 9 chips and only 3 would turn on thats why i think it needs a driver or something
     
  11. abhaymv

    Active Member

    Aug 6, 2011
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    It definitely needs a driver. It is my understanding that all high power LEDs need drivers. I've been working with high power LEDs for the past year due to a project of mine, and the simplest method I've come across to drive a high power LED is to use an LM317 as a constant current source. Do you know the voltage and current ratings of the LED? If the current is below 1.5 A, (which I suspect, since your LEDs sound like they're from LEDEngin and I've seen such LEDs there) you can use this circuit.

    I highly doubt you'll find a ready made solution inside an old computer. If you want a reliable driver, you'll need to buy one or use a circuit like the one I've linked you to.
     
  12. dvan

    Thread Starter Member

    Feb 8, 2014
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    fv 9-12 v . amps 900-1050.
    power supply 12v 1.5 amps
     
  13. dvan

    Thread Starter Member

    Feb 8, 2014
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  14. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    Now that's what I call high power :) Should there be a decimal point somewhere?
     
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  15. dvan

    Thread Starter Member

    Feb 8, 2014
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    yes you are right sorry i meant mA
     
  16. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    ALL LED's need some form of "current limiting"..
    That is commonly done with a resistor (for low power LEDs.. 20mA type) or with a "constant current driver"

    For this application (single 10W).. it can't get much easier (for newbies) than using a meanwell LDD series "driver" and a constant voltage power supply where output voltage is max VF of LED + approx. 2VDC or greater.

    Could you just use a resistor.. yes..
    Is a resistor the "best" solution for this.. no its not..
    Why you ask? because as you can see the Vf of the LED can vary.. Which can greatly effect the amount of current through it when a "fixed" resistor is used.

    So an "LED driver" is a better choice as it "self regulates" and will adjust the output voltage to ensure a "constant current" through the LED.
     
    Last edited: Mar 14, 2014
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  17. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    Meanwell also makes some great AC/DC constant current power supplies.
    So with the LDD you need a "constant voltage" DC output power supply to "feed" the LDD driver.
    With their AC/DC constant current power supplies you simply slap an AC plug on one end and wire the LED up to the other side and plug it right into a wall and voila..bright light.. (they are like having a "constant voltage" power AC/DC power supply and a LED driver in one package).. I like their LPF series for this.

    oh.. and DO NOT LOOK DIRECTLY INTO THE LED EVER..
    Even the smaller 1W LEDs or less are bright enough to cause permanent eye damage.
     
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  18. abhaymv

    Active Member

    Aug 6, 2011
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    I'm not really an fb person... Sorry...

    And I'd take mcgyvr's advice seriously. Trust me, you do not want to stare at a 10 W LED.
     
  19. takao21203

    Distinguished Member

    Apr 28, 2012
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  20. spinnaker

    AAC Fanatic!

    Oct 29, 2009
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    I do know. What are asking is not logical. At least 3 people have told you so now yet you refuse to believe.
     
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