nrf52840DK is not getting powered up

[jeevan t raj]

Hi,

We have a strange issue. We have got two nrf52840DK(PCA10056, 2.0.0, 2019.47). The nrf52840DK board is not getting powered up after the board rested in off for a long time say 2 days. when USB is connected no LED is turned ON, JLink drive not detected on the PC. I ensured that the USB cable using is a good one and the power source selector switch is in the required position. In this state, I can hear a feeble buzzing sound from the board(Guessing from any of the inductor is creating this sound). I had tried to connect a power supply of 3v to the External supply provision near the LiPo battery connector instead of powering from J2 USB. But still, no response received from the board. If the board is kept in a powered position for some time say 4 or 5hrs, then it starts to power up and works as usual. We have 2 52840DK's available. Both showing this behavior. But we have one nRF52832DK(PCA10040, V1.1.0, 2016.32), no such issues were observed on this 832DK. 

Please suggest possible ways to get rid of this issue.

[Amanda Hsieh]

Hi Jeevan, 

Please check that SW6 is on the DEFAULT position and SW9 is on the VDD position as the figure. 

 

Let me know this can help or not. Thanks. 

-Amanda H.

[jeevan t raj]

Hi Amanda,

Yes, SW6 is in DEFAULT position(Right)  and SW9 is in VDD position(middle).

[jeevan t raj]

Hi Amanda,

Thanks for the reply. It really helped. We will take care of the pull-down as you mentioned.

I can continue the development activities by doing this workaround in my DK.

[Vishnu Sukumaran]

Hi Amanda,

On the sticker it is mentioned - PCA10056, 2.0.0, 2019.47

[Amanda Hsieh]

Have you tried different usb cables and PC usb ports?

-Amanda H.

[Vishnu Sukumaran]

Yes, I have tried both. Couldn't find any difference.

[Amanda Hsieh]

Hi Vishnu Sukumaran, 

Please send me a private message with your e-mail address. Thanks. 

-Amand H.