820-2532-A I think my MCU is bad (U1400)

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  • rjpeek6
    New Member
    • Feb 2021
    • 7
    • USA

    #1

    820-2532-A I think my MCU is bad (U1400)

    I'm working on 820-2532-A board and I think the MCU (U1400) is bad (shorted). Initially I found a short across C7252 (PP5_S3_REG) and replaced it. With a little more troubleshooting I found no voltage (PM_SLP_S4_L) coming out of U1400. I then found a short to ground on PPMCPCORE_S0_REG. I removed R5425 to verify the short was on the output side of R5425 and removed C7565 & C7568 to verify they were not shorted but the short is still present. Is there anything else I should check?
  • piernov
    Super Moderator
    • Jan 2016
    • 4435
    • France

    #2
    Re: 820-2532-A I think my MCU is bad (U1400)

    Exact resistance to ground?
    OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

    Comment

    • rjpeek6
      New Member
      • Feb 2021
      • 7
      • USA

      #3
      Re: 820-2532-A I think my MCU is bad (U1400)

      4.7 ohms

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