23.3.2 Voltage Measurement

The V_DDIOx supply voltage is available as an internal input channel to the ADC. The voltage is divided by ten to allow the use of any internal ADC reference. This internal input channel to the ADC should only be used to measure the MVIO supply voltage once the V_DDIOx voltage domain has been released from POR and the voltage domain is ready to use as indicated by the RDY status bit and the VDDIOxRDYIF interrupt flag. To measure V_DDIOx/10, it is recommended to follow these steps:

1. Ensure that the V_DDIOx domain is active using the respective MVIO voltage monitors.
2. Configure the voltage reference for the ADC.
3. Select V_DDIOx/10 as the positive input to the ADC.
4. Run a single-ended ADC conversion.
5. Calculate the voltage using the following equation:
   $V_{\text{DDIOx}}=\frac{\text{ADC Result}\times V_{\text{REF}}\times 10}{\text{ADC Resolution}}$