Unlocking of NRF53 which was locked after flashing the code once

RE: Unlocking of NRF53 which was locked after flashing the code once

Bendik Heiskel — Wed, 05 Feb 2025 13:50:11 GMT

If the DCDC converters have been enabled, without the required inductors, the SoC is not powering up correctly. To recover a device in this state you will need to supply the DECD and DECR pins externaly, like you already have mentioned. Once these power rails are supplied externaly the nRF5340 should power up correctly and the device should then be recovered, to revert the regulators back to LDO mode. Once this have been done the external supply can be turned off, as the internal regulators should now be powering the device.

After this have been done you can flash a new application, but make sure the DCDC converter is disabled or you will need to do the recovery procedure again.

Best regards,

Bendik

RE: Unlocking of NRF53 which was locked after flashing the code once

Palaniappan — Fri, 31 Jan 2025 16:49:18 GMT

Dear Bendik

Thanks for your reply and suggestions.

We are using 2.6.1 version and we shall check with V2.8.0 with overlay file, you had mentioned. How ever the module is now in locked condition and connectivity is lost. Is there a way to unlock the module, so that after unlocking, we could try using the new version with overlay file suggested.

Thanks once again for your support.

Regards

Palaniappan

RE: Unlocking of NRF53 which was locked after flashing the code once

Bendik Heiskel — Mon, 27 Jan 2025 12:54:53 GMT

Hi Palaniappan,

Which version of the nRF Connect SDK are you using?

The way to configure the regulators have changed in v2.8.0, the Kconfig option are no longer used.

There is now devicetree nodes for configuring the regulators, to disable all the DCDC regulators you need a overlay file with:

&vregmain {
    regulator-initial-mode = <NRF5X_REG_MODE_LDO>;
};
&vregradio {
    regulator-initial-mode = <NRF5X_REG_MODE_LDO>;
};
&vregh {
    status = "disabled";
};

Best regards,

Bendik