NRF52840: VDD ramp-up to main() time.

Hi,

How much is the expected time period from the time VDD goes above 1.75V to main()? I am using a custom bootloader and am seeing a ~4.5s (yes seconds!) delay in getting to bootloader main(). When the debugger is connected this time is in the 100s of ms, which is what I would expect without the bootloader on first power up (1.8V VDD rail starting up). Here's a scope shot of my 1.8V rail (CH2) starting up and the IO (CH1) toggling (one of the first things done inside main()). Any help is greatly appreciated.

Thanks.

Hrishi