TX2 failed to boot on my designed board

I have designed my own board reference NV’s carrier board(P2597_B04).TX1 works well on my board.However,it cannot boot when I connect TX2 on my board,but it can boot on NVIDIA carrier board.
And I check the strapping pin(Jetson TX2 OEM Product Design Guide).Pin D9(UART1_TX) in my design have connected a level-shift chip(TXB0108).Pin G11、D8、H10、G10 are left floating.
Could you give us some advice? Thank you very much!

Hi, did you measure the status of Pin D9 when boot? It should be low. The level shift might pull it up during boot.

Thank you for your advice.I have measured the voltage of Pin D9 when TX1 is connected on my board.Before the button is pushed,the level of Pin D9 is 0V.When I push the button.The level of Pin D9 has raised 1.8V.
However,I have connected the TX2,the level of Pin D9 is always 0V.

If I remove the level-shift chip(TXB0108) Or replace it with SN74LVC2T45, can this problem be solved?

You can try removing level-shift.

TX2 can not boot when i remove the level-shift chip(TXB0108).I don’t konw why it is.

Not sure why this happen… you can compare the pin status between dev kit and your own board during power on process so as to confirm no violation.

I tested the power-related pins and power-up sequence without any problems.And I remove the level-shift chip(nothing connected to D9),the voltage of Pin D9 is still 0V during power on.I measured the NV CB,pin D9 is 1.8V.I was confused by this phenomenon.

You can try replacing it with SN74LVC2T45, there also can be other pin status issue, please compare the difference carefully.