ZYBO-Z7 - External power supply issue

[krjdev]

Hi,

 

I'm new in this forum.

Have an issue with the ZYBO-Z7 when I use an external power supply.

 

The board doesn't power-up very often when I turn on the power switch (SW4). eFuse?

The open circuit voltage from the power supply is between 5.45V and 5.50V.

 

When the board is powered over USB, everything works fine.

 

 

 

 

[JColvin]

Hi @krjdev,

I apologize for the delay. When you are using an external power supply, what jumper setting are you using on JP6? The power supply does sound like it provides the correct voltage.

eFuse won't be involved here; it's an internal setting within the FPGA if you wanted to encrypt it.

Thanks,
JColvin

[krjdev]

Hi @JColvin,

 

No problem.

The jumper setting on JP6 what I use is pin VU5V0 to pin WALL.

 

I have tried to switch a rectifier diode serial in the supply voltage. Now the board works fine.

The voltage drop after the diode  has helped.

 

According to your technical reference manual, the maximum voltage should be 5.7V.

I have measured the supply voltage with two different instruments (multimeter and oscilloscope).

Both of them display only max. 5.5V from the external power supply.

 

Edit:

Currently I have no laboratory power supply at home. So I cannot test in which voltage range the board works.