What's the minimum reference circuitry for running nrf52840 without RF(BLE stack)?

[nine-fox]

Hi,

May I ask what's the minimum reference circuitry for running nrf52840 without RF? Thanks.

My scenario is as follows.

1) RF, eg, Antenna is not needed

2) GPIOTE 1 channel and 1 UARTE is needed. No high accurcy needed.

3) Low power mode can be supported.

4) USBD is needed.

Based on my understanding, I draft a reference circuitry(I am using No.4 in product specification pdf). Would you please confirm, is it correct? Thanks.

[awneil]

As the RF is a key feature of the nRF, why would you not use it?

Or, to put the another way around, why not just use a "plain" microcontroller?

[nine-fox]

Hi Awneil, please see the reason I mentioned in

https://devzone.nordicsemi.com/f/nordic-q-a/72775/will-nrf5340-support-fast-key-press-detect

Since 5340 is not available yet, I need to find a way to resolve that issue

[JONATHAN LL]

Hi,

Maybe config 2 is what you where thinking, i removed the radio, external oscillator and the N.C components


But note: "When supplying power from a USB source only, VBUS must be connected to VDDH if USB is to be used."
From Config 1, the layout for the suplyting 


Regards,
Jonathan