LA-7551P 3V and 5V not present

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  • yulianbuds
    New Member
    • May 2019
    • 3
    • Indonesia
    #1

    LA-7551P 3V and 5V not present

    Hello everyone. I have problem in motherboard with code board LA-7551P
    My problem is 3V and 5V is not present. This is my result after measure the output on the IC RT8205LZQW
    - ENTRIP1 = 1.7V
    - ENTRIP2 = 1.3V
    - SKIPSEL, TONSEL, VREF = 2V
    - EN = 3.0V
    - BOOT1, BOOT2 = 4.5V
    - VREG3 = 3.4V
    - VREG5 = 5.0V
    Tags: None
    • mcplslg123
      Badcaps Legend
      • Jun 2015
      • 7262
      • india
      #2
      Re: LA-7551P 3V and 5V not present

      Pin23-PowerGood is present??? FB1/FB2 Voltage??

        Comment

        • piernov
          Super Moderator
          • Jan 2016
          • 4435
          • France
          #3
          Re: LA-7551P 3V and 5V not present

          Did you check for short to ground?
          OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

            Comment

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