Low power system on mode without VDDH

[JDBC]

On my custom board, VDDH is open and VDD is connected to 3.3V. I have been having trouble getting the board current consumption down to single digit uA. I have seen others post they could get to 2-4uA but setting up the clock and power registers correctly gets me to about 9mA.

Is it possible to enter system on low power mode with only VDD connected to power and VDDH open?  I have been able to enter BLE modes without issues.

Thanks,

JD

[Hung Bui]

Hi JD,

9mA sounds like a lot. I assume you are using nRF5 SDK. 

Could you try to test with \examples\peripheral\rtc and check what consumption you have ?
You should see around 10-20 uA  depends if the RTC timer timeout quick or slow. 

If it's in that range, you can try a BLE application, for example ble_app_blinky . It should be in the range of dozens uA. 

Could you send your schematic ? According to our reference design, VDDH should be connected to VDD when you setting it up for Normal supply voltage mode.

[Nancy Wang]

The system enters Normal Voltage mode when the supply voltage is only connected to the VDD , and VDDH
pin is open. What are the specific effects of this situation? During the burn-in and test, VDDH was not shorted to VDD and the test was found to be normal. 

[Hung Bui]

Nancy Wang : Are you adding more information to the question of JD. Or it's your own issue that you post here ? 
If it's your own issue, please create a new ticket. 

[Nancy Wang]

Thank you for the reminder, I have re-asked the question by creating a new ticket.