• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 98 subscribers
  • Views 134 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TDA4VM: nERR_MCU input state

Kevin Parmenter
Prodigy 100 points

Part Number: TDA4VM

Our design has a pullup resistor (10K) on the PCB connected to GPIO7 of the master PMIC.

We confirmed that the GPIO7 pad is pulled to 1.8V.

When we enable the error state machine, the PMIC resets, thus the PMIC thinks the pad is low.

When software reads the GPIO7 status register, it reports a low value.

Thus, the internal PMIC logic thinks the pad is low, but it is actually pulled high on the PCB.

Can you give us some help on how to debug this?

Once we get the PMIC to behave correctly based on nERR_MCU input being high, we want to connect it to a GPIO signal to test the function where an external signal can pull it low to initiate reset.

  • 0
    TI__Guru 69811 points

    Hello,

        Can you provide information regarding which PMICs you are using for TDA4VM?

        The NVM configures GPIO7 to have an internal pulldown, which is weak relative to the 10K external pullup you have applied.  Can you disable the pulldown to see if this has any impact?

    register address 0x0A, clear bit 3.  

    Regards,

    Chris

  • 0 in reply to Chris Sterzik
    Prodigy 100 points

    The HW and SW team found the problem, and it is a Garmin HW problem.  We are not getting good solder to that pin on a few boards, so it is intermittent.

    Now that they were able to get the pin soldered well enough, they will start testing the nERR_MCU functionality. This issue is resolved.