Arduino Uno

Microcontroller ATmega328

Working voltage 5 V

Input voltage (recommended) 7-12V

Input voltage (limit) 6-20V

Digital Inputs/Outputs 14 (6 of which can be used as PWM outputs)

Analog inputs 6

Constant current through input/output 40 mA

DC current for 3.3V pin 50 mA

Flash memory    32 KB (ATmega328) of which 0.5 KB used for bootloader

RAM        2 KB (ATmega328)

EEPROM 1 KB (ATmega328)

Clock frequency 16 MHz