NANO V3 based not soldered on the ATmega328 microcontrollers has a small size and can be used together with model boards for solderless wiring (breadboard). It has the similar structure with Arduino Uno/Duemilanove, but different size and with additional Analog In A6, A7. To reduce the size, components are mounted on both sides of the PCB.
The board uses a chip CH340G as converter UART-USB. Chip CH340G - is a budget solution. With an operating frequency in 12Mhz, yields a stable result of a data interchange.
NANO V3 can be powered via microUSB-port (up to 500mA). External power supply 6-9V unregulated to output VIN, or 5V external power source to a regulated output of 5V. The power supply is automatically selected with the maximum voltage value.