LTC2485 - Thermistor Measurement Circuit

Question

I have proposed circuit for measuring thermistor resistance as shown in the image attached. I am having trouble understanding the datasheet's section talking about differential input currents. I cannot figure out if I should use the external capacitor as discussed in that section. 
 
 Circuit description: 
 
 A 5V reference is Ref+, 
 Ref- is GND. 
 In+ is 1/2 the 5V reference 
 In- is the voltage on a second divider consisting of the NTC Thermistor and a precision, low TempCo resistor. 
 
 I am more concerned with precision than accuracy for this circuit. Any feedback is appreciated.

Yugel · Accepted Answer

Oh sorry, I have missed that part. 
 The differential input current errors in this device are effectively cancelled out due to the method of input sampling. This improves the DC accuracy of the ADC. Nothing to be really concerned about. 
 I see, you're correct about the range as it is still within +/-VREF/2. Although can you check if your thermistor will not be self-heating significantly given that your series resistor is only 200 ohms? At minimum resistance, the thermistor will dissipate around 10.2 mW. This might affect your measurements greatly. 
 Ratiometric configuration only means that the ADC reference and the excitation source is the same. In this way, any variations on the source would be cancelled out as in Eq. 3 below. 
 
 Source: A Simple Thermistor Interface to an ADC | Analog Devices 
 
 Thanks and regards, 
 Yugel)

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LTC2485 - Thermistor Measurement Circuit

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