Hi, Hayden,
QN9080 integrates a temperature sensor that is connected to one internal dedicated ADC channel as it is only for device internal temperature measurement.
Please, take a look at the QN908x Data Sheet, Chapter 8.17.2: Temperature sensor; and the QN908x ADC Configuration Guide, Chapter 7: Temperature measurement.
Also, you can find an example of ADC driver usage in addition with the temperature sensor inside the SDK examples (SDK examples > driver_examples > adc > temperature).
Regards,
Eduardo.