Questions about board design of AGX Orin Industrial

[jfdeg256]

Hello,

as we are finalizing our first custom carrier board for AGX Orin Industrial, we would need precisions on certain points :

**Power **

Because the board will be in an aeronautical equipement, the main power source is 28V DC. We will not have any button other that the recovery button for debug. We made our design in accordance with section 5.1 of the Design Guide.

This is our start sequence (VMON = 3,3V = SYS_VIN_SV) :

This is our stop sequence (VMON = 3,3V = SYS_VIN_SV) :*

• We didn’t connect SYS_RESET_N (pin L60) because we don’t plan to use it. Should we put it to pull up or pull down ?
• We connected POWER_BTN_N (pin L61) to a 10k pull-up to 3.3V as suggested by Figure 5-7. Is that correct ?
• As you can see, there is no loop-back between MODULE_SHDN_N (pin L52) and the power rails. Pin L52 is just connected to a LED for indication. As a result, if we try to shutdown the module by software, it will not shutdown, which is not a problem for us. Do you see any problem with that ?
• We provide 3.3V on pin L53 (SYS_VIN_SV) because we plan to use AGX Orin Industrial modules. We see on the Jetson devboard schematics that 3.3V is also provided. As a consquence, we deduce that we can use the Jetson devboard to flash the industrial module on the jetson devboard and then mount it on our board. Is that correct ? We also deduce that we can put an non industrial AGX Orin on a carrier board that provides 3.3V on pin L53 with no bad effect on it. Is that correct ?

Schematic checklist
In the schematics checklist, we saw that we should use 220nF capacitors on TX lines if directly connected to device.

However, on jetson devboard schematics, these are not present, while these lines are directly connected to the device :

We use the M2 NVME exactly like the Jetson devboard, should we put this capacitors ?

Same question regarding the RX lines of USB3 UPHY :

Best regards,

Jeff

[sgursal]

Recommend to prototype your proposed solution and test it thoroughly for any corner cases in your use case environment.
L60 SYS_RESET_N: A 10k pull-up to 1.8V is present on the module.
L61 POWER_BTN_N: Level shifter between module pin (3.3V) and SoC pin (1.8V) on module. Pull-up to 3V3 external to module is correct.
As for there is no loop-back between MODULE_SHDN_N (pin L52) and the power rails, you need to test this thoroughly and work out a solution which meets your intended use.
Flashing of Jetson module expected to work on our dev kit.

Regarding schematic checklist…
AC coupling capacitors are required for PCIe TX signals from both the Orin SoC and the connected PCIe device. If the connected PCIe device is on the other side of a connector, the AC capacitors should be located on the same side of the connector as the PCIe device. NVME involves using a M.2 connector. NVME is not soldered down on the board, hence the rules are different and follow PCIe specifications.

Same explanation applies for USB3.2 signals as it also involves using USB connector.