High Current Consumption in Secure DFU Bootloader for SDK 14.2

[SK]

Hi Everyone, 

I am using nRF52832 with SDK v14.2 and SD v5.0.0 on a custom chip. 

Recently i included DFU support to our application. It turns out that secure bootloader is drawing a constant current of >2 mA.

Before integrating secure bootloader support, we managed to bring down application current consumption during system ON (sleep mode) to 30 uA. But after integration with DFU, even during the sleep mode, i see a constant surge of over 2 mA. 

Could any of you guys let me know what can be the cause of bootloader taking in so much current? I found something in the forum which says that the bootloader has not been power optmized and has been considerably optimized in SDK 15.0.0 -> https://devzone.nordicsemi.com/f/nordic-q-a/36570/excessive-power-consumption-in-bootloader_secure_ble

But if i don't want to migrate to 15.0.0, is there a way this can be optimized for SDK 14.2? Please let me know. 

Thank you!  

[Simonr]

Hi

What might happen, is that your application crashes and constantly resets, which causes this excess current consumption as the bootloader is activated upon a restart. How are you measuring the current consumption? If you use the PPK for example, you should see the startup-spike over and over. You could also enable logging and call and print something at the start of your main loop, to check if the application is constantly resetting.

Best regards,

Simon

[SK]

Right now i am measuring average current using a power supply. If i run a standalone application without secure bootloader, it does not crash. Although application is not crashing w/ bootoader as well since i can see application is performing as expected. It's just the current consumption has gone high.

What would you suggest the reasons for application crashing with bootloader earlier?