PMIC_BBAT Pin Connection on Nvidia Jetson Orin Nano Dev Board

Issue Overview

The discussion centers around the PMIC_BBAT pin on the Nvidia Jetson Orin Nano Dev board and whether it can be left unconnected if not utilized in a carrier board design. Users have expressed concerns regarding the necessity of this pin, particularly in the context of hardware design and functionality.

Symptoms or Errors:

• Users are uncertain about the implications of leaving the PMIC_BBAT pin unconnected.
• There is confusion regarding the reference carrier board design, which only shows a diode (D4) populated.

Context:

• The issue arises during the design phase of custom carrier boards for the Orin Nano.
• Users are seeking clarification on best practices for pin connections when certain features are not implemented.

Hardware/Software Specifications:

• The discussion involves the Nvidia Jetson Orin Nano Dev board and its associated carrier board designs.

Frequency of Issue:

• The topic appears to be a common point of inquiry among developers working with the Orin Nano, suggesting that it is a frequent consideration in hardware design.

Impact on User Experience:

• Uncertainty regarding pin connections may lead to potential design flaws or malfunctions in custom implementations, affecting overall system functionality.

Possible Causes

• Hardware Incompatibilities or Defects: If the PMIC_BBAT pin is left unconnected improperly, it could potentially lead to power management issues.

• Software Bugs or Conflicts: While less likely, software configurations may not account for unconnected pins, leading to unexpected behavior.

• Configuration Errors: Misunderstanding the role of the PMIC_BBAT pin could result in incorrect designs that do not function as intended.

• Driver Issues: If drivers expect certain pins to be connected, leaving them unconnected might cause errors in power management.

• Environmental Factors: Poor power supply design could exacerbate issues related to unconnected pins.

• User Errors or Misconfigurations: Developers may misinterpret documentation regarding pin usage, leading to unnecessary concerns.

Troubleshooting Steps, Solutions & Fixes

1. Diagnosing the Problem:

   • Verify whether the PMIC_BBAT pin is connected in your carrier board design.
   • Check the reference design documentation from Nvidia for guidance on necessary connections.

2. Gathering System Information:

   • Use schematic capture tools to review your carrier board layout and confirm pin connections.

3. Isolating the Issue:

   • Test with a prototype carrier board that includes a connected PMIC_BBAT pin versus one that does not to observe any differences in functionality.

4. Potential Fixes or Workarounds:

   • According to user feedback, it is acceptable to leave the PMIC_BBAT pin unconnected if it is not needed for your specific application.
   • Refer to Nvidia’s official documentation for any updates or recommendations regarding this pin.

5. Best Practices:

   • Always consult the latest hardware design guidelines from Nvidia before finalizing your carrier board layout.
   • Consider implementing a diode (like D4) as shown in reference designs if there are uncertainties about power management implications.

6. Documentation and Updates:

   • Regularly check for firmware updates that might address power management issues related to unconnected pins.
   • Ensure that you are using compatible drivers that align with your hardware configuration.

Unresolved Aspects:

• Further investigation may be needed into any long-term effects of leaving the PMIC_BBAT pin unconnected, particularly in varying operational environments.

By following these guidelines, users can effectively navigate concerns surrounding the PMIC_BBAT pin on the Nvidia Jetson Orin Nano Dev board while ensuring optimal performance of their custom designs.