SPRADO8 March 2025 AM62L
The recommendation is to connect the ADC0 analog supply VDDA_ADC0 to the recommended power supply rail in the processor-specific data sheet.
ADC0 inputs are not fail-safe. Applying a voltage (> Absolute Maximum Ratings) to any of the ADC0 inputs before the processor ADC supply ramps is not recommended or allowed. The input applied (based on the input level) can cause residual voltage on the processor supply rail and can cause board start-up issues. Refer Absolute Maximum Rating table of processor-specific data sheet. In case supply rails that are available before the processor supply ramps are required to be monitored, the recommendation is to connected these inputs to the ADC0 through a switch. The switch can be controlled by processor GPIO or power good signal from any of the supply source including PMIC.