DA14706 hibernation


I tried to run pmu_wakeup_demo from github.com/.../BLE_SDK10_DA1470x_examples on DA14706 DevKit.

When I enable hibernation mode, power consumption decreases to 200 - 300 nA, and seems it is really hibernation. (It can't wake up by reset or power switching, only by connecting Vbus).

Vbat voltage is 3.3 V.

The main problem is Vsys voltage in hibernation is about 2.9 Volts and I still can power external devices from it (after connection external device to Vsys, consumption increases to 10 mA). 

As I understand based on documentation, device should open sysbat switch and as a result power off all peripheral, connected to Vsys.  

I tried to set FORCE_VBAT_VSYS_SW register manually for open switch this switch, but it had no result. 

My device in “Shipping mode” should disable all external peripheral, I hope I do something wrong.

What can be problem?

Do I need to prepare DA14706 to hibernation mode? May be you have some guidelines for it? 

Does it really possible to disable Vsys at all, or I need to use external power control scheme?