I am planning to use the AD22105 as a replacement for the obsolete DS1821 sesor. In my design it operates as a standalone thermostat in reverse polarity as shown on figure:
In datasheet for the AD22105 it is mentioned that “AD22105 can be used to detect transitions from higher temperatures to lower temperatures by programming the setpoint temperature 4°C greater than the desired trip point temperature. <...> In this mode, the logic state of the output will indicate a HIGH for under temperature conditions.”. Still this is unclear to me how this works. How would the sensor figure out that I want to put it in this mode and not to just set the setpoint temperature somewhat higher?