Custom carrier board for Jetson Nano doesn't boot up (MOD_SLEEP still low)

[mateusz]

Hello,

I designed custom carrier board based on dev kit B01 schematic. On dev kit I don’t have any problem with boot system, but on carrier board unfortunately occur (I use the same SOM and system).
schematic:

I don’t have any logs on uart (RX line has 4.7k pull up 1.8V), MOD_SLEEP is still low state.
Osciloscope screen during check above schematic:

I check power sequence and it is compatible with nvidia docs.
I read few topic on forum where I found few solution (pull up on UART RX line, remove pull up on force recovery) but these don’t help me. I tried use 10uF on C120 for long delay to power_en high but it doesn’t help too.
Do you have any additional ideas what is wrong.

[Trumany]

Hi, what’s your module version? Please share a photo of that. You power logic circuit is same to devkit, no issue found. What about other power rails on carrier board? Are they all ON after module rails?

[mateusz]

I use SOM from devkit: PN: 945-13450-0000-100. I found what I made wrong. I powered carrier board circuit before powered Jetson. I changed power sequence so problem is resolve. Thank you.