LED backlights voltage drop

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  • budm
    Badcaps Legend
    • Feb 2010
    • 40746
    • USA
    #1

    LED backlights voltage drop

    This is interesting numbers from the service manual.
    6.36V Drop PER LED, 19 LEDs x 6.36 = 120V.

    I wonder what kind of LEDs are being used, may be TWO LEDs inside one body?
    https://www.badcaps.net/forum/showthread.php?t=35465
    Attached Files
    Never stop learning
    Basic LCD TV and Monitor troubleshooting guides.
    http://www.badcaps.net/forum/showthr...956#post305956

    Voltage Regulator (LDO) testing:
    http://www.badcaps.net/forum/showthr...999#post300999

    Inverter testing using old CFL:
    http://www.badcaps.net/forum/showthr...er+testing+cfl

    Tear down pictures : Hit the ">" Show Albums and stories" on the left side
    http://s807.photobucket.com/user/budm/library/

    TV Factory reset codes listing:
    http://www.badcaps.net/forum/showthread.php?t=24809
    Tags: None
    • Ltank
      Badcaps Veteran
      • Jun 2013
      • 776
      • USA
      #2
      Re: LED backlights voltage drop

      I had some post on a Samsung LED set about some LEDs. I can't think if the name now, I am responding from my phone. That company made dual LEDs but the four j pins that solder it in were not the correct pin assignment to be serially linked. It may take some digging to get the correct voltage/current/pin assignment.

        Comment

        • ben7
          Capaholic
          • Jan 2011
          • 4059
          • USA
          #3
          Re: LED backlights voltage drop

          I've seen some [relatively] high power LEDs that operate at or around that voltage.

          A quick look online suggests that there are such things as dual white LEDs:
          The Cree X-Lamp ML-C series are basically two LEDs in one package, and they can be wired if series or parallel.
          Muh-soggy-knee

            Comment

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