17.6.10.1 User Control of the Voltage Reference System
To enable the temperature sensor, write a one to the Temperature Sensor Enable bit (VREF.TSEN) in the VREF register. The temperature sensor is not available on the DA1 devices.
The temperature sensor can be redirected to the ADC for conversion.
The Bandgap Reference Voltage Generator output can also be routed to the ADC if the Bandgap Output Enable bit (VREF.BGOUTEN) in the VREF register is set.
The Bandgap Reference Voltage Generator output level is determined by the CALIB bit group (VREF.CALIB) value in the VREF register. The default calibration value can be overridden by writing to the CALIB bit group.