External USB charging bag can take the data cable out of the charging bag, and then connect it to the data interface of the school bag, you can charge. The backpack itself does not bring a charging bank, just designed a convenient charging USB jack, you can put the charging bank in the bag, connect the cable, through the outside jack, do not need to open the backpack zipper can also charge the design. The charging bank can not be charged, usually the following kinds of working faults:
1. USB charging head is damaged.
2. The constant current charging circuit inside the charging treasure is damaged, usually by overheating and burning the main charging chip.
3. The line between the charging head and the charging bank is not connected well, or the line is broken. Expansion: mobile power, English mobile power pack (MPP), also known as charging treasure, travel charger, etc., is a portable charger that integrates power supply and charging functions, which can charge mobile phones and other digital devices anytime and anywhere or standby power supply. Mobile power supply generally consists of lithium cell or dry battery as a storage unit. Different from the internal configuration of the product battery, also called external battery. Generally equipped with a variety of power adapters, usually with large capacity, multi-purpose, small size, long life and safe and reliable characteristics, is anytime and anywhere for mobile phones, digital cameras, MP3, MP4, PDA, handheld computer, handheld game consoles and other digital products power supply or standby charging function products.