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 an 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. This 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