The Arduino Nano is a small, complete, and breadboard-friendly board based on the ATmega328. It has more or less the same functionality of the Arduino Duemilanove, 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.
In the Arduino Nano V3.0 (Economy) it use CP2102 USB to TTL chip Instead of FTDI.
Operating Voltage (logic level) 5 V
Input Voltage (recommended) 7-12 V
Input Voltage (limits) 6-20 V
Digital I/O Pins 14 (of which 6 provide PWM output)
Analog Input Pins 8
DC Current per I/O Pin 40 mA
Flash Memory 32 KB of which 2 KB used by bootloader
SRAM 2 KB
EEPROM 1 KB
Clock Speed 16 MHz
Dimensions 0.73 x 1.70 inch