nRF52840 USB power circuit

[Johann_Papp]

Hi Nordic Tech Support Team,

my customer will use ISP1807-LR (InsightSIP module with nRF52840 SoC) for a project where he don't need USB.

Question:

What is the best solution in this case:

a). VBUS not connected and VCC_nRF with 3.3V supply 

b). VCC_nRF not connected and VBUS with 5.0V supply

c). VCC_nRF with 3.3V suppyl and VBUS with 5.0V supply 

Many Thanks! 

Johann

[Andreas]

Hi Johann,

 

Option 1: VBUS not connected, VCC_nRF = 3.3 V (or anything between 1.7V and 3.6 V). Remember to short the VDD pin with the VDDH pin.

 

VBUS does not need to be connected when the USB peripheral is not used. Also the capacitor on DECUSB does not need to be populated.

 

Best regards,

Andreas