Will any functionality be lost if the Power On/Off sequencing is implemented without the Button MCU for the Xavier NX?

Hi. I have been going through the Product Design Guides for Nano and the Xavier NX. Also, took a look at the P3449_B01_Concept_schematics.pdf and P3509_A01_Concept_schematics.pdf. I have a few questions.

  1. On the Xavier NX, will implementing the Power Sequencing without a Button MCU and using an analog circuit instead lead to loss of some functionality?

  2. It seems like the Button MCU on the Xavier NX:
    a. holds POWER_EN high
    b. provides Power Button functionality
    c. handles the SHUTDOWN_REQ* from the module
    d. handles DC Jack Unplug.
    e. handles SYS_RESET*
    Is there anything apart from these features that the MCU is responsible for?

  3. The Button MCU chip has BMCU_ACOK input. What are the use cases for this pin?

  4. I don’t see the circuitry BMCU_ACOK and BMCU_PGOOD in Nano’s Module Power ON/OFF Schematic. Does this mean that the Nano’s carrier board doesn’t check for these when powering on/off.

  5. I don’t see the circuitry to handle SYS_RESET* either in Nano’s Schematic. How does Nano carrier board handle SYS_RESET*?


For #1 and #2, there is pin function description table in design guide for reference, all can be implemented with or without MCU design.
For #3 and #4, ACOK is for auto power on detection. It is J40 on Nano board.
For #5, it is used as input and not handled by carrier board on both NX and Nano.