MSP430F6725A: Connection with VCCAUX3

Hi,

Yes, you can if you don't use AUXVCC3, connect it to DVSS.

Eason

Hello Eason,

Thank you for your reply.

Please tell me again.
Is it necessary to connect VCCAUX3 to VCC in the following cases?

Customers utilize an external 32.768 KHz to make the DCO accuracy comparable to an external clock using FLL.
However, XT1 is not used because it uses a bypass route that does not enter XT1.

Customers also do not use the RTC.

Best regards,
DDdoor

Yes. You can find this in the datasheet:

Hello Eason,

Thank you for your reply.
Does the meaning of low frequency oscillator include not only XT1 but also external 32KHz outside XT1?

Best regards,
DDdoor

For peripherals controlled by backup system, it is default supplied by DVCC. That means you can control all the peripherals and make all the oscillator work without backup system. For when the MCU will use the backup system, you can refer to this. Sorry to make you confused.

Hello Eason,

I don't think it's correct.
Because, in the block diagram, it is connected from DVCC to Vbak (Backup Subsystem) via Charger.
The Charger setting is disabled by default, so I don't think it will be powered by DVCC by default.
Also, the Battery Backup System is listed in parentheses as RTC_B module,
and this time the customer is using MSP430F6725A, which is RTC_C.
I don't think the Battery Backup System description applies to this device.
There is no such thing as VBAT on this device.

Best regards,
DDdoor