MB-N2 with LDO setup, can program but the circuit does not boot


Is there anything else I need to do from a software side?
I’ve added code to disable DC converter, not helped.
void setup() {
// Disable DCDC power converter
NRF_POWER->DCDCEN = 0x00000000;

I’ve ordered a new version that strictly complies with the reference design and has dcdc passives. But it would be nice to know what the problem is. I prefer LDO setup because it is more suitable for me.

Below is the schema. I’ve disconnected p4,p5 thinking that boot
time DFU reset might be causing problems, but it did not help. It just does not boot.



Hi @kursatu,

Have you uploaded the SoftDevice to the MB-N2? What kind of adaptor you are using to upload firmware?

Best regards,


Thanks for the reply guohui.
I am programming it via DAPLink 1.0. Please note that SDIO, SCLK are connected to the USB receptacle in the schema and I’ve made a custom USB connector for it. It is wired via breadboard wires to the corresponding DAPlink pins.
I can burn the bootloader via Arduino IDE and upload my sketch , the upload verification succeeds for both cases. Though I had to increase the capacitor at DEC4 to 10uF, lower values was causing memory verification errors.
But my sketch does not work, I don’t see its Bluetooth advertisement name.
The blinky sketch does not work either. I’ve checked via various GPIO pins, no high voltage anytime. I did not try to debug via RX/TX connections and Serial.print’s.

I thought that softdevice and bootloader is already included in MB-N2 or burning the bootloader via Arduino IDE would take care of the softdevice+bootloader upload. Also, I don’t need OTA-DFU programming at this stage, maybe later. The wired programming would probably work and be more practical for my product with the initial release, even if I need to use one-time pads for initial fw programming.

If something is missing on the software side, what do I need to do exactly to upload my sketch?
If so please provide steps/commands or documentation link for getting mb-n2 working

I also have Nordic DK52 and Eclipse/gcc setup, but need to use Arduino, don’t want to port whole code.

  • I’ve merged using mergehex tool the softdevice s132 2.0.1 with my .hex from Arduino build folder
    mergehex -m C:\Users\kursa\AppData\Local\Temp\arduino_build_54202/Sketch.redbear.ino.hex C:\Users\kursa\Downloads\s132_nrf52_2.0.1\s132_nrf52_2.0.1_softdevice.hex -o Sketch.hex
    I drag and drop it onto the DAPlink drive.

1- It works with the Nano2 , even after erasing the chip using nRF52_EraseChip.hex
2- It does not work with my circuit.