AD590 Temp sensor scaling issue with INA196_1

Hi all,

I’m looking to use the INA196_1 to power and receive the signal from a AD590 temperature sensor.

The AD590 transmits a very small current at 1uA per degree. It returns Kelvin values between 218.2K (-55C) and 423.2K (+150C). So 218uA to 423uA range OR 0.281 to 0.423mA. So used the 16x gain setting (would be nice to be more but good for now)

So on x16 gain with a 0.300mA signal I get ADC value of ~5400 or 42mV. I’m now lost how this relates to the 0.300mA signal?

Note i reverted the circuit back to x2 gain and a 4mA signal and get adc value ~6430 as expected. So things point to the hardware working as expected.

Thanks for all input
Andy