How to know the specs of each LED from a flat panel

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  • SuperDuty
    Badcaps Veteran
    • Mar 2011
    • 299
    • France
    #1

    How to know the specs of each LED from a flat panel

    Hi,

    I have taken apart a dead LED flat panel (burnt electronics), and picked up the two backlight LED strips. They are made of 40 white CMS LEDs in series (size is about 5mm x 3mm), that are VERY bright, powered by a 38V power supply.



    I was thinking about reusing them for various projects, but how do I know the voltage they require to be powered ? Can I just divide the voltage with the number of LEDs of each strip ?

    Thanks

    Thanks
    Tags: None
    • tom66
      EVs Rule
      • Apr 2011
      • 32560
      • UK
      #2
      Re: How to know the specs of each LED from a flat panel

      Most white LEDs will operate around 3.5V to 4.5V per LED. Most will glow, but not very brightly, at around 2.7V to 3V. Most likely, the set up is around 4 strips parallel of 10 LEDs (3.8V/LED) with each parallel strip being current balanced by a controller IC, to ensure even brightness.

      Current could be measured easily, by inserting an ammeter in series with one of the return wires.
      Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
      For service manual, schematic, boardview (board view), datasheet, cad - use our search.

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