LG 50PV250 Y Buffer meltdown

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  • mangozac
    Member
    • Feb 2013
    • 36
    • Australia

    #1

    LG 50PV250 Y Buffer meltdown

    We were watching TV the other night and *bang* (as in made an actual noise), no more picture. Sound was still working but the ominous smell of vaporised semiconductor hung in the air!

    Popped the back off and sure enough the top Y Buffer ICs had a big hole in it. I turned power back on and could see one of the buffers on the bottom half starting to glow too. So I removed both buffer boards and tested the Y-sus voltages Vy and Vsc, both of which were in spec at 150 and -190V (Vsc is confusing as measuring with the polarity indicated on the PCB it actually gives a positive voltage).

    My question to you knowledgeable fellas is this: do I just source new Y buffer boards or is it likely there's something else wrong with the Y Sus board that isn't obvious and damaging the buffers? Is one fried buffer likely to cause the rest to pop? The reason I ask is because that Y Sus board doesn't seem particularly common so could be a headache to replace.

    The Y Sus board is a EBR69839001
    The buffer boards are EBR69839101 and EBR69839201

    Thanks!
  • ljintexas
    LJinTexas
    • Jan 2015
    • 669
    • USA

    #2
    Re: LG 50PV250 Y Buffer meltdown

    I may have those..let me check.

    Comment

    • mangozac
      Member
      • Feb 2013
      • 36
      • Australia

      #3
      Re: LG 50PV250 Y Buffer meltdown

      Originally posted by ljintexas
      I may have those..let me check.
      Cheers mate, let me know what you find!

      Comment

      • ljintexas
        LJinTexas
        • Jan 2015
        • 669
        • USA

        #4
        Re: LG 50PV250 Y Buffer meltdown

        Mine are different...2010 model..numbering system is even different.

        Comment

        • mangozac
          Member
          • Feb 2013
          • 36
          • Australia

          #5
          Re: LG 50PV250 Y Buffer meltdown

          Thanks anyway. Do you reckon I need to change the Y Sus board too, to make sure the new buffers don't get fried?

          Comment

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