UNO R3
Reference: UNO R3
Microcontroller: ATmega328
Operational Voltage: 5v
External power (recommended): 7-12v
External power (limits): 5-20v
Digital I / O pins: 14 (of which 6 with PWN function)
Analog pins (input): 6
DC Current I / O Pin: 40 mA
DC Current 3.3V Pin: 50 mA
Flash Memory: 32 KB (of which 0.5 KB are occupied by the bootloader)
SRAM: 2 KB
EEPROM: 1 KB
Speed: 16 MHz