MAX825 and DS1819 as mentioned in data sheet have similar functions with few tweaks like
MAX82_EXK..........-40 °C to +85 ° C
MAX82_EUK .........-40 °C to +125 ° C
The watch dog timer is 1.6s for MAX815 and for DS1819 its 1.12s
Pin configuration and functions are similar, if timer differences and temperature ranges are acceptable then the products could be used as drop in replacements for each other.