На с.13
паспорта, глава "INPUT CAPACITOR SELECTION", первый абзац:
Цитата
The input bypass capacitor plays an important role in proper regulator operation, minimizing voltage transients at the input and providing a short local loop for the switching current. Place this capacitor close to the ADP3050 between the IN and GND pins using short, wide traces.
Аналогичное требование само собой имеется и в паспорте виртуально применённого Вами аналога
LT1765, на с.6, главы "Vin" и "GND", 2-е и 4-е предложение соответственно:
Цитата
Keep the external bypass capacitor and catch diode close to this pin.
Цитата
Keep the path between the input bypass and the GND pin short.