nRF52840 - VDDH Operating Voltage at 1.8V

[Peter Carlson]

Hi Support Team,

I’m designing a custom PCB using the nRF52840 based on "Circuit configuration no. 6" from the nRF52840_PS_v1.0.pdf. On our design, VDD_nRF = 1.8V which is below the VDDH operating voltage (see section 5.3.8.1).

I have no plans to the REG0 so should I still connect VDDH to VDD (1.8V) or should I leave VDDH disconnected?

[Andreas]

Hi Peter,

 

Connecting VDDH to VDD will leave the chip operating in 'Normal voltage mode', in which REG0 will be disabled. You can see more in the POWER section  in the PS.

 

Best regards,

Andreas

[nick_haman]

I am in same situation.  The reply didn't answer the question directly.  Should VDDH be connected to 1.8V?

[postrudolph]

I can not solve my problem. Hope you can explain more detail.

basket random

[Kaja]

Hi, 

this is an old case, please create a new case, and ask for a HW review if you need an engineer to look over your HW design.

When using 1.8 V as supply, operates in normal voltage mode, and then VDDH should be connected to VDD. 

See main supply and see reference design no. 3 and no. 5.

Best regards,
Kaja