There are three reasons for the buzz:
1. The voltage is unstable, the charger is used for too long, and the connection is in poor contact;
2. It is recommended to check the charger temperature and charger socket.
3. You can change the charger and then check the phenomenon.
Improvement method: The normal charger will not have that sound, because the mobile phone charger charging voltage is very small, it is recommended that you go to change the charger, so as not to damage the phone.
Mobile phone charger, also known as mobile power supply, charging treasure, in fact, is composed of a stable power supply (mainly voltage regulation power supply, providing stable operating voltage and enough current) plus the necessary constant current, voltage limit, time limit and other control circuits. The output parameters marked on the original charger (wire charge) : such as output 5.0V\/1A, output 5.0V\/1500mA-11200 refer to the relevant parameters of the internal regulated power supply.
Mobile phone commonly used lithium ion (li-ion) battery charger is used constant current limited voltage charging system, charging current is generally used about C2 ----, that is, two hours of charging rate, such as 500mAh battery using 250mA charging about two hours to reach 4.2V and then constant voltage charging