Other Parts Discussed in Thread: TMUX6104
I am designing an RTD measurement device based on ADS1261. The excitation current requirement range from 100nA to 1mA, I understand that I need an external current source to support this full range.
I need to choose the Rref for ratiometric measurement to cover this range. From the datasheet and the excel sheet, Vref should be 0.9 < Vrep < 5.
That would mean that I need to have a resistor selection network with different resistor values for each range. Would a TMUX6104 work for this, I chose it due to its low leakage current ?
Does a 10Meg rref make sense @100nA range ? This will evaluate to 1V for Vref.