Jetson AGX Orin INA3221 power monitor layout

Good afternoon. As I’ve done with other Jetson devices, I’m trying to understand the power rail layout of the Orin. I haven’t been able to conclusively determine this from the existing documentation like the L4T docs or the Product Design Guide. Per the former, there are four active INA3221 channels: 3 on 0x40: VDD_GPU_SOC , VDD_CPU_CV, and VIN_SYS_5V0; 1 on 0x41: VDDQ_VDD2_1V8AO.

For example, are VDD_GPU_SOC and VDD_CPU_CV subsets of (branch downstream from) VIN_SYS_5V0? Is VDDQ_VDD2_1V8AO in parallel to VIN_SYS_5V0, or is it also also a child of VIN_SYS_5V0?

Thanks!

Hi, VDD_GPU_SOC and VDD_CPU_CV are included to SYS_VIN_HV, VIN_SYS_5V0 is for SYS_VIN_MV, and VDDQ is included to VIN_SYS_5V0.

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Thanks for the information! So if I understand correctly, the tree structure for the power sources and monitors is like:

Power Jack
|-- SYS_VIN_HV
    |-- VDD_GPU_SOC (0x40, channel 1)
    |-- VDD_CPU_CV (0x40, channel 2)
|-- SYS_VIN_MV
    |-- VIN_SYS_5V0 (0x40, channel 3)
        |-- VDDQ_VDD2_1V8AO  (0x41, channel 2)

making VDDQ_VDD2_1V8AO is the only power monitor channel that is a subset of another (VIN_SYS_5V0)?

Yes, and VIN_SYS_5V0 is SYS_VIN_MV.

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