Adn507 [best] Info

The input voltage is too high relative to the output, combined with high current. (e.g., 18V in to 3.3V out at 400mA = ~6 watts of heat dissipation, far exceeding the package limit). Solution: Reduce input voltage, add a heatsink to the PCB ground plane, or use a switching pre-regulator.

Even robust components fail when subjected to environmental stress or circuit design errors. If your device using an ADN507 is malfunctioning, look for these symptoms: adn507