Recently, a friend went to Hong Kong and brought back an iPad 4. When he came back, he found that the original power charger was not compatible with the mainstream interface standards in China. It could only be used on some large plug banks, which made it inconvenient to go out. In fact, many people have encountered such problems and even become accustomed to them. However, it is estimated that there are not many people who have explored in depth. Today, we might as well take this opportunity to introduce