in the datasheet for the AD7747, figure 38 on page 25 (rev.0) shows how to connect an RTD. However, I don't understand how to choose the resistor between REFIN(+) and REFIN(-). Should it be equal to (or rather a little bit higher than) the maximum expected value of the RTD?
Secondly, can I change the circuit so that REFIN(+) is connected to VDD, REFIN(-) to VIN(+) and VIN(-) to GND? The RTD I want to measure is unalterably connected to ground.
Thanks in advance,