Identifying backlight LED

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  • schmo
    Member
    • Jan 2014
    • 11
    • DE
    #1

    Identifying backlight LED

    Hi

    i got a Blaupunkt 40/233I tv with a broken backlight.
    I disassembled the tv and looked for bad caps but they are ok. The backlight connector delivers ~30V under load
    So I disassembled the panel and found 2 broken leds on the led stripes.

    Can you help me to find the correct package and correct values?
    Attached Files
    Tags: None
    • diif
      Badcaps Legend
      • Feb 2014
      • 6978
      • England
      #2
      Re: Identifying backlight LED

      You need to measure the length and width of the LED to identify the package and determine if they are 3V or 6V.

      https://www.ebay.co.uk/itm/BUSH-40-2...-/332097789746
      Last edited by diif; 08-31-2018, 12:34 PM.

        Comment

        • schmo
          Member
          • Jan 2014
          • 11
          • DE
          #3
          Re: Identifying backlight LED

          Hi

          Thanks for your message

          The led is 4mm x 3mm

          There are 20 leds in series. So 30V / 20 = 1,5v?

          Thanks for the link. There they are really expensive. I would like to buy them from my local electronics dealer.

          Greetings

            Comment

            • budm
              Badcaps Legend
              • Feb 2010
              • 40746
              • USA
              #4
              Re: Identifying backlight LED

              If the 20 White LED (3V LED) in series so the total Vf = 20 x 3V = 60V.
              The 30V looks to be the feeding Voltage to boost converter circuit to drive the 20 series- connected LED.
              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

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