This is the new Arduino Uno R3. In addition to all the features of the previous board, the Uno now uses an ATMega16U2 instead of the ATMega8U2 chip.
• ATmega328-AU microcontroller
• Input voltage – 5-10V
• 5V Electric current : 500MA
• 3.3V Electric current : 50MA
• 14 Digital I/O Pins (6 PWM outputs)
• 6 Analog Inputs
• 32k Flash Memory
• 16Mhz Clock Speed
Main Changes from the Old Version:
•TWI interface and the IOREF in the top and bottom connectors. This change keeps the board 100% compatible with the current boards and shields, but adds possibilities for new shields.
•Reset button moved from center of board to corner near USB connector. This is great; makes it much easier to access with a shield on.
•Larger heatsinking copper area for the LM117 regulator
•Uses an Atmega16U2 instead of the Atmega8U2 on the previous version. Opens up more possibilities for USB apps!
•Arduino can only work at 5V voltage. When it comes to 3.3V Level module, IO can’t be connected to it. The Level should be changed, like the SD card, Bluetooth module and so on. Sainsmart UNO R3 can work at 3.3V voltage by switching on the button. At this time, IO port is 3.3V and it can work with 3.3V Level module.
1x SainSmart UNO R3 Improved 2013 Version MEGA328P ATMEGA16U2 board
1x USB cable
The Uno now uses an ATMega16U2 instead of the ATMega8U2 chip. Faster transfer rates and more memory.
No drivers needed for Linux or Mac (inf file for Windows is needed and included in the Arduino IDE). The ability to have the Uno show up as a keyboard, mouse, joystick, etc.
3.3VV/5V Supply Voltage and IO Voltage is optional. More 3.3V modules supported, such as Xbee module, Bluetooth module, RF module, GPRS module, GPS module, LCD5110 Backlight and so on, but the original version can only support 5V IO.
Add SDA and SCL pins next to the AREF. In addition, there are two new pins placed near the RESET pin. One is the IOREF that allow the shields to adapt to the voltage provided from the board. The other is a not connected and is reserved for future purposes. The Uno R3 works with all existing shields but can adapt to new shields which use these additional pins.