Arduino Uno R3 ATmega328p SMD ver 8-bit Arduino Microcontroller Motherboard Development Dev Board Pin Header | Micro USB | Squareport USB (Type-B) | USB Type-C - Squareport (Type-B)

Arduino UNO R3 SMD uses surface mount version of the Atmega328P instead of the through-hole version. the board is based on the ATmega328 (datasheet). It 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. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started.

Microcontroller: ATmega328
Port: Squareport USB (Type-B) | USB Type-C port | Micro USB port
Operating Voltage: 5V
Input Voltage (recommended): 7-12V
Input Voltage (limits): 6-20V
Digital I/O Pins: 14 (of which 6 provide PWM output)
Analog Input Pins: 6
DC Current per I/O Pin: 40 mA
DC Current for 3.3V Pin: 50 mA
Flash Memory: 32 KB (ATmega328) of which 0.5 KB used by bootloader
SRAM: 2 KB (ATmega328)
EEPROM: 1 KB (ATmega328)
Clock Speed: 16 MHz