nRF5340 regulator inductors

[sg953]

Hallo,

I have a question reading the datasheet. It states:

" If a regulator is only to be used in LDO mode, the inductor for this regulator is not needed. "

I want to use all regulators in LDO mode only, so I want to omit the 10µH inductors completely to save PCB space. In this case should the DCCR, DCCH and DCCD pins be left unconnected, or they should be connected directly to the corresponding other pins (short circuit instead of inductors)?

Would this LDO mode only design mess up Zephyr? Does it require DC-DC mode?

Thank you in advance.

PS: an other question: can I also omit capacitor from DECUSB if USB will be not used at all?

[Andreas]

Hi,

 

Correct, if you want to use a certain regulator in LDO mode then you do not need the respective inductor between the DCCx and DECx pin. If all regulators are in LDO mode then you do not need any external 10µH inductor. Zephyr should not care about which mode is used, and by default LDO should be configured (you need to enable DCDC explicitly).

 

If you do not plan to use USB then you can remove the DECUSB cap, and any supply/cap on the VBUS pin.

 

Best regards,

Andreas