TegraX1 not booting up properly

Hi all,

I posted this issue in TK1 forum by mistake, moving it here now.

https://devtalk.nvidia.com/default/topic/970987/jetson-tk1/tegrax1-not-booting-up-properly/ Link to thread in TK1 forum

We designed a Carrier Board for NVIDIA TX1. We followed the jetson dev kit schematics. The sections that we excluded from our design are M.2 Key E, SATA connector, HDMI connector, GPIO expansion headers, Display connectors, Camera expansion, JTAG header and Debug header. For the GPIO Expanders section, only U28 is excluded.
The problem is when we turn ON the NVIDIA TX1 using the Power Button on the Carrier Board, it doesn’t boot up. We have traced the problem to the CARRIER_PWR_ON pin of NVIDIA TX1. CARRIER_PWR_ON is an output signal from NVIDIA TXI, and it controls the Enable Pin of 5V regulator. If a pulse is applied for a very small duration at the Power button, the CARRIER_PWR_ON pin becomes HIGH after some delay and the board boots up just fine. But if the pulse at Power button is a little longer, say 500ms, the CARRIER_PWR_ON signal goes high immediately turning ON the 5V, 3.3V and 1.8V regulator. As a result the board doesn’t boot up. When the CARRIER_PWR_ON goes high while POWER button is still low, we have the boot-up problem. We have verified this by using a switch between the CARRIER_PWR_ON and enable pin of the regulators; first we press the power button (duration of press doesn’t matter), and after we release the power button we turn ON the switch between CARRIER_PWR_ON and Enable Pin, the board boots up.
We have NVIDIA Jetson TegraX1 developer’s board, and it doesn’t have this issue. It boots up even if the Power button is not released before the CARRIER_PWR_ON signal becomes high. We have followed the same design and we are having problem with the boot up.

@Trumany

“Did you check the power up sequence as figure 4 of OEM DG said, especial the status of RESET_OUT?”
Yes we’ve checked above power up sequence and RESET_OUT pin goes high after Power button is pressed

“Also please check if R19 is removed or not? It is the PU of RESET_IN that can’t be removed.”
R19 is stuffed, it acts as PULL UP for RESET_IN signal.

We can manually boot up the board if we disconnect R507(CARRIER Power on signal to Enable pin of 5V Reg) and apply HIGH signal to 5V Reg Enable pin after one second of pressing Power Up button.

According to power up sequence, CARRIER_PWR_ON should be high after power button goes high. Although dev kit can boot up even when the power button is not released and CARRIER_PWR_ON goes high, it should not be treat as correct action. So the short pressing has no problem and if you want to implement long pressing to boot up safely, a timing control of CARRIER_PWR_ON is necessary.

For locating the root cause of different behavior between your board and dev kit, as it looks more like some interface between carrier board and module causing this problem, suggest to check the interface signals status to see if they are different to dev kit or some are pulled in wrong level, such as UART, I2C etc. , which could hold module boot up.