how to reduce backlight volts/current JVC LT-49C550

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  • jimbofz
    Badcaps Veteran
    • Apr 2013
    • 539
    • uk
    #1

    how to reduce backlight volts/current JVC LT-49C550

    This model had backlight strips replaced 6 months ago and reduced backlight from 10 to 5. You have guesses it, the customer despite my advice turned it back up to 10 so now backlights have failed.
    I have reapired the TV and checked the voltages feeding each strip and I would like to know how to reduce the voltage /current feeding the 2 backlight loops. The chip used on this UMC TV is 0cp8128 please see the enclosed picture of the data sheet.
    Attached Files
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    • jimbofz
      Badcaps Veteran
      • Apr 2013
      • 539
      • uk
      #2
      Re: how to reduce backlight volts/current JVC LT-49C550

      sorted
      i doubled the value of r14 and r9 reducing backlight current by 30% this should stop the leds from being driven flat out
      i still have acceptable pic even with menu set at 6 for b/l
      shame no one seemed interested

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