The Arduino Uno R3 Atmega328P Atmega16u2 compatible is a microcontroller board based on the ATmega328. It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz crystal, 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.
The Uno differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it features the Atmega16U2, programmed as a USB-to-serial converter.
This 100% Arduino Uno R3 compatible controller module has the Atmega16u2 USB controller and uses the original board layout in compliance with the open source license. Means you get technically the same product, but you save 50% because you don’t pay for the brand name on the PCB.
Specs and features of Arduino Uno R3 Atmega328P
Operating Voltage: 5V
Input Voltage: 7-15V
Digital I/O Pins: 14 (of which 6 provide PWM output)
PWM Digital I/O Pins: 6
Analog Input Pins: 6
DC Current per I/O Pin: 20 mA
DC Current for 3.3V Pin: 50 mA
Flash Memory: 32 KB (ATmega328P)
…of which 0.5 KB used by bootloader
SRAM: 2 KB (ATmega328P)
EEPROM: 1 KB (ATmega328P)
Clock Speed: 16 MHz
Length: 68.6 mm
Width: 53.4 mm
Weight: 25 g