About atxmega128a3u

Some basic settings of the device
Power supply range : -0.3v to 4v
Crnt in/out of Vcc/Gnd pin max : 200mA
Pin vltg wrt gnd & Vcc : -0.5 to Vcc+0.5
Maximum CPU clock frequency depends on Vcc



The voltage ratings for pins (with Vcc between 2.7 and 3.6v)
Input-
           High level : 2 to Vcc+0.3
           Low level : -0.3 to 0.8
Output-
           High level: 2.4 minimum (0.19 typical)
           Low level : 0.4 maximum (0.05 typical)