The UNO R3 board compatible with Arduino has micro controllers: ATmega328.
This UNO board compatible with arduino has 14 digital input/output pins (of which 6 can be used as PWM outputs) 6 analog inputs, a 16 MHz crystal oscillator, a USB connection, a power jack, an ICSP header, and a reset button.
Input Voltage (Recommended): 7V ~ 12V
The package includes: 1x UNO R3 board compatible
microcontroller: SMD (Surface Mount Chip)