tx1 VDD supply diff with handbook described

Hi everyone.

In the JetsonTX1_OEM_Product_DesignGuide, it says that the vdd_19v_in should be 5.5v~19.6v, and the tx1 can work well.

But I found that when vdd_19v_in drops below about 16v, the tx1 doesn’t work.

Does anyone know why this happen or or anybody have met the same situation?

Thanks

You mean drop from 19V to 16V? If so, it could cause a shut down, as said in Figure 7 of OEM DG.

Hi Trumany,

Thanks for your reply.

I didn’t drop the voltage, I just test a few different value for vdd_19v_in, and I found that voltage below 16v doesn’t work.

And when I use 16v, I measured that VIN_PWR_BAD# is about 4.8v, which mean vdd_19v_in is a good value. So I don’t know why.

So would anyone give some help ?

It is strange… Did you probe the power up sequence as Figure 4 of OEM DG said, to check the timing and the voltage value?

Hi Trumany,

Thanks for your so many rely.

So have you use a lower value of vdd_19v_in such as 10v(or some like this) drive the nv tx1 carrier board & core baord successfully ?

Thanks very much!

Sure, it works well even with lower level than 10V.

Hi trumany,

I’ve know the reason why I can’t use 16v drive the tx1 work: it’s because when tx1 por up, there is a big short time current (much bigger than later it works normally), and it’s bigger than my digital power source peak current.

When I use another powerful digital power source tx1 work well at lower driven voltage.

But I don’t know why there is so big a current, maybe cap charge?

Good to hear this. Usually there will be a peak current when system power on which is same as all other electric device, that will draw the output voltage of source to low, for those power source with bigger output capacitors, the voltage drop will be lower than those with smaller capacitors.

Hi Trumany,

I think I need to improve my basic hardware knowledge. ^_^

Thanks for your help!