- Jan 02, 2018 -
What determines the speed of the charging of the cell phone?
For the same cell phone, the efficiency is determined by data line internal resistance (including USB contact resistance at both ends), the output voltage of the charging head and the maximum output power of the three.
The output of the charging head passes through the charging line. Due to the internal resistance of the charging line, the voltage of the power management component at the end of the mobile phone will be reduced. In general, the internal resistance of the charging current multiplied by the data line is the pressure drop of the data line. At the same time, the power management chip will set a minimum acceptance voltage, such as 4.7V, which will not be charged under this value.
The same charging head with different charging line on the same mobile phone charging, the charging head will dynamically adjust the output current (correction: mobile phone power management chip should take the initiative to reduce the input current, the charging end will change, in order to ensure the voltage reaches) mobile phone terminal can meet the requirements.