I am currently using the ADT7420 temperature sensor for my project. The board I used is the EVAL-ADT7420-PMDZ board from ADI. The datasheet indicates the response time of this sensor is very quick(around 5-10s) but I found it that it took 2 mins to report room temperature(~22C) when I took the sensor out from my home refrigerator(~0C). I use all the default settings (13 bits resolution and etc.)
I wonder what might be the problems to drag down the response time?
Any advice would help and thank you in advance.
As stated on page 23 of the ADT7420 datasheet, thermal response is also heavily influenced by the mass of the PCB. A different board was used for the thermal response plots on the datasheet. This app note with some tips on how to layout your PCB for your temperature measurements may help.