12 volts from the USB port
To the USB port of a personal computer to receive a voltage of 5 V from the source power.
Many peripheral devices to exchange data with a computer through the USB port, but also nourished by him.
In order from the USB port to power the device, designed for voltage 12V, you can make this increase, the diagram of which is shown. He gives a voltage of 12 V at a current of 80 mA.