I am using STM32F030c8t6 in my device which is battery operated. I want to monitor a standard 3.7V Lipo battery voltage so I used a voltage divider at the battery and divider output is set to 3.3V which goes to ADC pin of Controller.

[HRawa]

1. Is it ok to set 3.3V as a divider output which goes to ADC pin?

2. The external voltage at VDDA pin (We have given the same VDD as VDDA) show some fluctuations while ADC monitoring so can you suggest the best possible way to monitor battery voltage using Internal reference voltage?

3. If I use internal ADC reference voltage that does divider output voltage matters? How much divider output should be set?

4. Please share ADC configuration for using internal reference voltage. 

5. Single ADC channel can allow using internal reference voltage?