nRF52840 stops working

RE: nRF52840 stops working

Marcio Montenegro — Sat, 08 Sep 2018 13:42:25 GMT

Hi HSh,

Check j-link pinout.I am using the following pins:

VTref pin 1 ( connect to 3.3V),

SWIO pin 7

SWCLOCK pin 9

and any GND pin ( pin 4 to 20 )

www.segger.com/.../

RE: nRF52840 stops working

HSh — Thu, 06 Sep 2018 23:33:29 GMT

Thank you. It eventually did not work. I just connected everything as you mentioned to the nRF52840 DK, but it is not working. Thanks tough.

RE: nRF52840 stops working

Marcio Montenegro — Thu, 06 Sep 2018 20:15:33 GMT

2 smd leds + smd resistor. I used LM1117 regulator for 3,3V power supply.

2 x10uF tantalum capacitor near LM1117 and 1 100nF capacitor near vnRF pin.

circuits4you.com/.../

RE: nRF52840 stops working

HSh — Thu, 06 Sep 2018 19:31:21 GMT

Thanks for your prompt reply. I will try all GND pins. BTW, I can see some components on your PCB, do I need any extra component for Jlink or USB?

RE: nRF52840 stops working

Marcio Montenegro — Thu, 06 Sep 2018 19:02:02 GMT

Yes, I did. I don't have a standalone j-link.I am using j-link from Silicon Labs EFM32 zero gecko (debug out function).

https://www.silabs.com/products/mcu/32-bit/efm32-zero-gecko

No pull up resistors.

Remember there are several GND pins : pin 1, pin 44, pin 32

Pin 55 : vnRF connect to 3.3V

Pin 47 : VBUS connect to GND ( no USB)

Regards,

RE: nRF52840 stops working

HSh — Thu, 06 Sep 2018 17:19:52 GMT

Hello,

Can you please let me know how did you connect the holyiot to JLink for porogramming? I directly connected SWCLK, SWDIO, V_nRF, and GND to both original Jlink Segger and nRF52840 DK. However, I am not able to programm the holyiot. Is there any trick? Do I need any pull up resistors?

Thanks

RE: nRF52840 stops working

Marcio Montenegro — Wed, 04 Jul 2018 09:48:49 GMT

I found the problem:

I forgot to connect left ground and right ground.Also I will put a ground plane under the module.

Apologize for any inconvenience.

RE: nRF52840 stops working

AmbystomaLabs — Tue, 03 Jul 2018 21:42:56 GMT

You should get a multimeter and verify Vdd nRF is really there after you disconnect j-link. The standard j-link provides power when connected.

RE: nRF52840 stops working

Marcio Montenegro — Tue, 03 Jul 2018 21:36:58 GMT