- Jan 09, 2018 -
Where is the difference between fast full / low pressure and fast charge
We all know that the formula of power W is the voltage Vx current A, so there are three ways to increase the charging power: the current is constant, the voltage is increased, the voltage is constant, the current is increased, and the voltage and current are raised together. Most of the current fast charging scheme was selected the first high voltage mode, such as Qualcomm Quick Charge 3 has appeared in this year's flagship machine, and OPPO is the choice of second schemes launched a fast charging scheme of low voltage high current VOOC.
For the 5V-1A ordinary charging method in the early stage, the first AC power adapter 220V reduced to 5V DC, and then in the mobile phone end was adjusted to about 4.2V (lithium ion battery charge cutoff voltage 4.2V); high voltage fast charging scheme is the first time by 220V AC power adapter to 9V DC, and then in the mobile phone terminal decreases to about 4.2V; VOOC low voltage high current fast charging scheme is the first direct to about 4.2V, without a mobile phone terminal voltage conversion again.
Therefore, because the lithium battery has a tolerance voltage limit, whether it is high voltage, fast charging or high current and fast charging, it is eventually 4.2V charged into the battery. But users with high voltage and fast charge must have some experience. In the fast charging process, the fever of mobile phones is more serious, mainly due to the energy loss of the mobile phone's two time depressurization, and the high temperature is a major reason for the aging of electronic components. The high current fast charging scheme has completed all the voltage conversion on the power adapter, so the mobile phone will not buck down for the two time, and there will be no serious fever.