Wierd power down behaviour when AONHV_CAN pins high (1)

[tobias.johansson1]

Hi!

Used AGX: AGX Industrial

We are having an issue with the power down sequence not being completed as expected.

Used pins (as GPIO):
E59, F59, B62, C61, H61, B61

E59, F59, B62 have been used successfully as “GTE/AON”-input pins for quite some while, but C61, H61, B61 have recently been added for this use.

Expected use: Use C61, H61, B61 as inputs (to/into AGX) to be monitored using gtechip0 etc.

Pinmux file used to generate DT file(s)

However: When using these pins as inputs, we see strange behaviour when it comes to the power down sequence of the AGX, especially the CARRIER_POWER_ON not going low (0), which keeps our carrier board powered on - even after “AGX Linux OS” has shut down.

Image taken from OEM Product Design Guide v2.5

This behaviour only seems to happen when two (or more) of these pins (C61, H61, B61) are high (1) when shutting down the AGX - if only one, or none of these pins are set (1), the power down sequence, including CARRIER_POWER_DOWN behaviour, is successful.

I cannot find anything in the OEM Product Guide or the “Industrial Migration Guide v1.2” which states some underlying use for these pins/something blocking them from being used as regular “GTE/AON”-pins.

Any insight in why this might happen?

Thanks

[kayccc]

Sorry for the late response, have you managed to get issue resolved or still need the support? Thanks

[Trumany]

Hi, the carrier supply to these pins should be off earlier than module during power off, so as to protect module pins are not affected by back drive current from carrier.