The Nano is a compact board which is fully compatible with Arduino NANO board. The Nano is a small, complete, and more or less the same functionality of the UNO, but in a different package. It lacks only a DC power jack, and works with a Mini-B USB cable instead of a standard one.
Same as the nano, arduino nano can be powered via the Mini-B USB connection, 6-20V unregulated external power supply (pin 30), or 5V regulated external power supply (pin 27). The power source is automatically selected to the highest voltage source.
Each of the 14 digital pins on the Nano can be used as an input or output.They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. In addition, some pins have specialized functions.
The Nano has 8 analog inputs, each of which provide 10 bits of resolution.By default they measure from ground to 5 volts, though is it possible to change the upper end of their range using the analogReference( ) function. Analog pins 6 and 7 cannot be used as digital pins. Additionally, some pins have specialized functionality.
The Nano has a number of facilities for communicating with a computer, another Arduino, or other micro controllers. Such as UART TTL (5V) serial communication and I2C (TWI) and SPI communication100