Hi Joachim/Bob, So I have come back to this and selected a couple of 10K NTC thermistors that will work well for us. My question before I submit my schematic to others for review is whether there is any advantage of placing the RBias resistor on Top of the Thermistor vs. below the Thermistor as you have shown? Seems like whether it is placed on Top or Bottom one still takes the divider measurements in same fashion across the NTC but maybe I am missing something. Initially I had put the RBias on top of the NTC in which I was planning on using the Load Switch on the AIN3/REFN1 input on the ADS1220 to minimize self-heating in the NTC and also minimze current drain when we are not taking a measurement... From the snapshot below TH+_OUT and TH-_IN are the signal paths to a cable that will have the NTC thermistor on the end and TH-_IN is the return path for the signal loop. Anything either of you guys see that should be changed? I am going to update the R-C filter a bit to reduce the value of R14 to values closer to what you show in the ADS1219 Datasheet. Regards, Frank
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