nRF52 DK board stopped working and does not power up anymore

[AimHigh]

Hi,

It all happened today after being used the board for a month. when I tried to turn on the board it does not blink LED5 nor does it show up in the device manager. I to find info online with no success. I am in deep trouble now, need some quick suggestions, please help me with this.

[Amanda Hsieh]

Hi, 

Please try/confirm and reply regarding to this post. 

Best regards,

Amanda

[AimHigh]

Hello, thanks for the reply. I followed some of the methods from the trailing post.

4. Have you tried to press the IF BOOT/RESET button while power cycling the kit? It should then show up as a Removable Storage Device named "BOOTLOADER". Then you can drag-and-drop the J-LINK interface MCU firmware found here (v170724) onto the storage device to reprogram the JLINK firmware.

This seems to give me some hope, but now LED5 is only flashing continuously for every second. 

And in device manager, it says unknown device. What shall I do now?

[AimHigh]

I am trying to measure TP1 and TP2 test pins on nRF52 Dk, and is it ok if D+ reads 2.8V and D- reads 0V always?

[Amanda Hsieh]

I tested it here, and I also read 2.8V on my DK, so that seems to be normal yes.

Maybe the flash is damaged or electrostatic discharge. 

-Amanda

[AimHigh]

when you say flash is damaged Do i need to change PCA10040 Chip on board? or something else?

[Amanda Hsieh]

I would suggest to change a new DK is easier. 

-Amanda

[AimHigh]

Could you try the method mentioned below and validate me on what happened on your side?

In my observation, I tried to enter boot mode using a coin battery (not connected to USB) and it did enter boot mode(except that LED flashes every second. Same situation as if it is connected to USB and not recognized). 

But the strange thing is when entered boot mode using a coin battery, LED5 would blink and die out quickly. Like as if something is shorted on the board. And this phenomenon is difficult to observe when it is connected thru the USB port. 

Does that give any clue?

[Amanda Hsieh]

Sorry for the delayed answer. I haven't been able to reproduce this on my side. I will update this case if we have further information.

-Amanda

[AimHigh]

Sure, i am looking forward to your response. 

Cheers!