Need help changing (single board TV) LED Driver's Current ( FB Resistor )

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  • Ancient1
    Badcaps Veteran
    • Dec 2019
    • 275
    • Israel
    #1

    Need help changing (single board TV) LED Driver's Current ( FB Resistor )

    Elco (?) 50" Smart TV. Backlight ( BL) issue.
    Single Board : TP.SK708D.PC821
    I bought new BL set . - OK
    Power up : Blip . Protection.
    Led Tester shows current at 34.2 mA , Previously it was 42.1 mA
    Solution : Change current output .
    The BL IC is marked on the photo and datasheet is QOB33535 Datasheet(PDF) - Schneider Electric (alldatasheet.com)
    Calculating according to the datasheet - see attached photo :
    With ILed = 34.2mA , equation #1 is RFb = 400mV / 34.2 = 11.7 Ohm , and with 42.1 mA we get 9.50 Ohm . i.e I should look for 9.5 Ohm R on the FB, pin $5, line . ​
    I need to change 9.5 Ohm to 11.7 Ohm
    But I can not find 9.5 Ohm resistor (array ?)

    I hope someone has a clue .
    Thanks
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