The Arduino Uno Rev3 has an OpAmp (TI LMV358IDGKR datasheet) where the non-inverting input ("CMP") is connected via a voltage divider to Vin. The OpAmp's supply is connected to 5V.
On the Arduino Uno Rev3 product page (click) they specify the recommended and limit ratings for the boards input voltage:
Looking at the LMV358IDGKR absolute maximum ratings i am wondering why having (in the case of say input voltage > 11.4V) a voltage above 5.7V at the OpAmp's input ("CMP") isn't a problem? For my understanding the OpAmp will blow up at say 15V input voltage?!
(Well voltage at barrel jack might be ok up to roughly 12.5V because there is a diode between power jack and VIN, but above?)