The part is trimmed at 2.28V, thus internal reference to use for calculation should be 2.28V.
ADT7411
Production
The ADT7411 combines a 10-bit temperature-to-digital
converter and a 10-bit 8-channel ADC in a 16-lead QSOP. This includes a band gap temperature sensor...
Datasheet
ADT7411 on Analog.com
The part is trimmed at 2.28V, thus internal reference to use for calculation should be 2.28V.