[NRF52833] Custom board work only in debug mode.

[mati553]

Hello,


I have the custom design. Schematic is below:

I use Visual Studio Code and nRF Connect SDK V1.6.1. My programer is NRF52833DK
I used example code (zephyr/samples/basic/blinky) then I change gpio to TRACE0 and add the line: NRF_CLOCK->TRACECONFIG= 0x00, because I use traces pin as gpio.
When I use debug mode program works fine, but when I connect only the power supply program doesn't start. During a debugging session, when I unplug SWDIO, SWCLK and NRESET then NRF52833 works continuously.

[Bendik Heiskel]

Hi,

While in a debugging session the regulator is forced to LDO mode, but the Zephyr blinky example enables the DC/DC converter by default. So when not in a debugging session the DC/DC is enabled, and since the inductors needed for the DC/DC are not present on your custom board the regulator is not able to operate correctly.

To disable the DC/DC converter you must add CONFIG_BOARD_ENABLE_DCDC=n to prj.conf.

 

Best regards,

Bendik

[mati553]

Thank you, It works.