This level is decided by considering the current charge level of your device and then it gradually increases to charge your device at the highest 5V voltage level. Obviously there are usually two types of chargers for such gadgets, usually tablet charge with the help of 15V chargers whereas smartphones use the chargers with the peak voltage of 5V. This new feature of the Mediatek SoC will help the smartphone to get charged at a good rate though their primary competitor Qualcomm have also integrated with the same feature by the name of Quick Charge and as far as comparison is comparison is concerned then Qualcomm takes the win because it has made the charging 75% faster (The exact mechanism is not known). The new Mediatek devices will be equipped with this feature.