USB charging generally does not exceed 500mA, the voltage is 5V, and all power is 2.5W maximum
Android mobile phone support standard USB interface 5 volt voltage 1 amp or 2 amp current, the output power of this voltage and current is 5 watts to 10 watts, Android mobile phone can be directly used to charge, because Android mobile phone can use the USB interface of the computer to charge, that is, Android mobile phone can use at least 2.5 watts of power can be charged normally. But compared with the current Android phone charger, the charging speed of the USB socket will be slower.