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.