nRF52840 DK LED5 is not glowing SW9 is on VDD mode and the PC doesn't Detect the board

[Sarkar]

Hi Support Team,

1. I have a problem with nrf52840 DK board, it was not detecting in nRF Connect SDK for DEsktop.

2. Previously it was working but now it is not working, I could not find the issue.

3. The LED5 is not blinking but while I change the SW9 from VDD to Li-Po mode the LED5 blinks for some times.

4. I checked the USB Cable with other nRF boards I have and they are working.

5. Then I followed this post nRF5340 DK LED5 is bright SW9 is on VDD mode and the PC doesn't Detect the board not working

and checked the VDD nrf and gnd pin and the voltage was 0V but when I check other pins like the 5V pin or normal Vdd pins they are working fine.

Then I also checked the micro usb cables pins and there I found 5V with respect to ground.

Please suggest some solution for this.

Thanks You.

Regards,
Sadasiba

[Kenneth]

Hi,

Maybe the board have been damaged some way, maybe an ESD/ESO event. 

Can you just do some "investigation" around the Power switch on the DK? Maybe short-circuit it, just to check it may be somewhat broken?

Can you try to ground VIO_REF on P20 to see if that make any difference?

Best regards,
Kenneth

[Sarkar]

Hi Kenneth,

Thanks For replying.

According to your suggestion I grounded VIO_REF with on P20 once and after that when I measure the voltage between Vdd nRF with ground it is showing 3.01V but still the LED5 is not blinking nor the board is detected by my Laptop.

Best Regards,
Sadasiba

[Kenneth]

Hi,

LED5 should not be blinking if it works, it should be ON continously. 

Can it be a missing driver problem? Please check out first answer here:
I am trying to develop a Globalstar ST150M The project board is a Nordic Semiconductor nRF 52840 DK running an Arm Cortex M4 CPU. 

Kenneth

[Sarkar]

Hi,

I know the LED5 should be continuously on but the thing is it is not even turning on.

I checked the Link you shared, So I can assure you that it is not a driver problem, as I am working with other nRF boards and they are working fine with my Laptop.

Best Regards,
Sarkar

[Sarkar]

Hi Lisa,

Thanks for replying.

But I can not understand what you are saying, as I am new to nRF. Can you share some kind of Link for my  understanding, I think that will be helpful.

Thank you.

Best Regards,
Sarkar