Based upon the original open source design featuring the ATmega16U2 USB serial chip. Cheaper clones use the CH340G USB-TTL serial chip. If you’re looking to level up your Arduino project, the Mega 2560 is a great place to start. It’s based on the Atmega2560 chip which provides a huge number of IO pins and functionality:
54 Digital Input/Output pins (14 with hardware PWM capability)
16 Analogue Inputs
4 UART ports
Whilst being a much larger and more capable board, the Mega2560 still clocks at 16MHz, just like the Uno, which means it won’t run faster than a Uno, but you do get a lot more functionality to use within those 16MHz. Something to note about the Mega2560 is the use of a 16U2 which is programmed as a USB-serial converter rather than a standalone FTDI chip as many previous Arduino boards used.
This is the revision 3 model board which contains the following changes:
– 1.0 pinout: added SDA and SCL pins that are near to the AREF pin and two other new pins placed near to the RESET pin, the IOREF that allow the shields to adapt to the voltage provided from the board. In future, shields will be compatible both with the board that use the AVR, which operate with 5V and with the Arduino® Due that operate with 3.3V. The second one is a not connected pin, that is reserved for future purposes.
– Stronger RESET circuit.
– Atmega 16U2 replaced the 8U2.