Power sequencing question and Recovery mode

Autonomous Machines Jetson & Embedded Systems Jetson AGX Xavier
1

we design a new carrier board for AGX Xavier. According to the official Power-sequencing guideline(Power up with button and MCU), the MCU control the power sequencing.
1.> MCU set the POWER_BTN_N to high level, MODULE_POWER_ON to low level and VIN_PWR_ON to low level.
2.> delay 200ms
3.> MCU pull the POWER_BTN_N down then set the VIN_PWR_ON up.(MV/ HV will be supplied power)
4.> delay 800 ms then set the MODULE_POWER_ON up.
5.> Waiting for the CARRIER_POWER_ON signal to high level(if failure, it won’t go on).
6.> delay 200ms
7.> set high level for POWER_BTN_N

my question:
1.) is the procedure alright?
2.) Why the kernel board enter the recovery mode when power up? I had been compared the carried board(official) and my carried board. It looks like alright, but i’m not ensure it.what i need to attention?
3.) FORCE_SHUTDOWN_N would be in high level, according to the design guideline, if STANDBY_REQ_N(High) and FORCE_RECOVERY_N(LOW), the kernel board would enter the recovery mode.but the FORCE_RECOVERY_N is always to keep high level when power up. It confuses me for long time.

2

Hi, the Figure 13. Power-OFF to On Sequence (Power Button Case) shows the correct timing of all related signals. Are you using the same MCU of reference design?

3

Hi sominic_82,

Have you started carrier board design? Any further issues to be clarified?

4

I got the reason.

The D_ForceShutdown is the key thing. I don’t know what the reason? The specification mentions this is a OD type. But it’s obviously not right. I try to pull up the pin, When the module power up, the pin never set to the high level.

The STM32 MCU can control the power up sequencing right, but it should add some periphery circuits. Module Power -on is key signal.

5

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I design a new carrier board for AGX Xavier 16G.
1> MCU set the VIN_PWR_ON to high Level.
2> delay 100ms, MODULE_POWER_ON to high Level.
3> delay 50ms, VIN_PWR_BAD_N to high Level.
4> delay 10ms, CARRIER_PWR_ON to high Level.
5> delay 300ms, set high level for POWER_BTN_N.

Do not operation, why the carrier board enter the normal mode when power up?