a1990 820-01041

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  • lordgeny
    Badcaps Veteran
    • Apr 2016
    • 223
    • Italia

    #1

    a1990 820-01041

    a1990 820-01041 stuck on 5v
    i have no PP3V3_G3H_RTC_X

    it also in diode mode i read 0.025

    i readed its generated from u6960 and also i have no voltage in vin at c6961
  • mon2
    Badcaps Legend
    • Dec 2019
    • 14031
    • Canada

    #2
    Re: a1990 820-01041

    What is the voltage of PPBUS_G3H @ F7000, pin # 2 ?

    When 5 volt (default) from the external adapter is the power source, U7000 will enter BOOST mode for the PPBUS_G3H rail.

    Remove the battery and use only the external USB C power adapter and measure this voltage.

    Do check also F7000, pin # 1.

    If you see a low voltage on this rail, then remove all power -> remove F7000 and then power up again with the external adapter.

    Then check again the voltage of PPBUS_G3H

    @ F7000, pin # 1 - what is the reading without a load (no fuse) ?

    Comment

    • lordgeny
      Badcaps Veteran
      • Apr 2016
      • 223
      • Italia

      #3
      Re: a1990 820-01041

      F7000 pin 1 no voltage
      f7000 pin 2 no voltage

      Comment

      • lordgeny
        Badcaps Veteran
        • Apr 2016
        • 223
        • Italia

        #4
        Re: a1990 820-01041

        i used another usb-c (right side ) and i have 12v on f7000/f7001 pin 1 without fuse

        Comment

        • lordgeny
          Badcaps Veteran
          • Apr 2016
          • 223
          • Italia

          #5
          Re: a1990 820-01041

          putting back fuse i have pulsing voltage around7v/8v both side of fuse

          Comment

          • lordgeny
            Badcaps Veteran
            • Apr 2016
            • 223
            • Italia

            #6
            Re: a1990 820-01041

            this port is using u 3200 , and i have also PP3V3_G3H_RTC_X but no 20v ... ...

            Comment

            • lordgeny
              Badcaps Veteran
              • Apr 2016
              • 223
              • Italia

              #7
              Re: a1990 820-01041

              ok i found that ub400 was heating , so i removed and now ppbus its back at 12v , i need new ic

              Comment

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