One is 1A, the other is 2A; 1A is suitable for MP4, mobile phones and other devices; 2A is dedicated to tablets.
At present, most of the charging treasures on the market have 2 charging ports, 1A port and 2.1A port. This power bank is a mobile phone that is compatible with almost all USB data lines. Many friends who bought a power bank do not know which charging port should be used for their mobile phone. Or use it indiscriminately, using this interface today and using that interface tomorrow.
If the charger is equal to or less than 5V1A, such as: 5V1A, 5V700MA, 5V600MA, etc., use the 5V1A interface. Most mobile phones use the 1A interface, many models from Apple, Samsung, and China.
Some models use the 2.1A interface (the mobile phone charger is written as 5V2A), such as Samsung NOTE2, NOTE3, NOTE4, S5 and other mobile phones; Apple IPAD tablet (5V2.4A), you can also use the 5V2.1A interface Charge. Just a little slower than the charger that comes with the iPad.
There are also rare mobile phone chargers marked with 5V1500MA. It is best to use the 1A port of the power bank to charge. Although it will be slower than the charger, it is very safe. If you use the 2.1A port to charge more than the mobile phone is designed to charge The charging current range belongs to overload use and affects the life of the mobile phone. The principle is to charge the mobile phone with the charging port of the charging treasure that is equal to or less than the output current marked on the mobile phone charger. In this way, the efficiency is the highest and the number of charging times is the most.
If you use the wrong interface, for example, Apple mobile phones can also be charged with a 2.1A interface. However, because the charging current far exceeds the design current range of the mobile phone charging interface, the power bank and the mobile phone generate relatively large heat.
Correct use of power bank There are several types of mobile power sources, how to choose the right power bank, and how to use the 1A and 2.1A charging ports of the power bank. The number of times is reduced, which also affects the life of the mobile phone. Do your best to avoid it! If you use the 5V1A interface to charge the Samsung NOTE2, NOTE3, NOTE4, S5, IPAD tablet, you can also charge it. Because the charging current is much smaller than the normal value required by the mobile phone, the charging time will be very long and the number of charging times will be very small, because the mobile phone also consumes a lot of power from the power bank due to the standby state during the charging process. In a sense, the power bank becomes an external battery for the mobile phone.