what you think about ADC backward measuring supply voltage in microcontroller? It looks interesting for battery-powered devices.
The idea is:
- Connect constant voltage (some voltage reference IC) to ADC input (not to Vref!)
- Set AVcc as reference for microcontroller ADC
- Get ADC value
- Calculate ADC reference (our AVcc) from ADC result
- is this commonly used method?
- can that method be better than measuring Vcc using voltage divider with ADC reference connected "conventionally"?
My question is inspired by this.