From the datasheet, when TS1, TS2, TS3 are configured for general purpose ADCe, the input voltage range is 0~1.8V(VREG18).
My customer wanted to know in this case, whether these pins are not pulled up by internal resistors and use the external 5V Vref, as shown below.
The reason for the question is that my customer is worried that the temperature sampling error when ADCIN is 1.8V, they hope the temperature accuracy to be less than 1℃ at -25~65℃.
Could you please give your comments? Thank you!