With the development of high technology, many people cannot do without electricity and are gradually surrounded by various electrical appliances; And mobile electronic devices such as smartphones and tablets are even more 'opportunistic'.

Now we will also see some new USB C connectors that may eventually replace USB. Samsung, on the other hand, has its own USB connector and Apple's Lightning connector, both breaking through industrial custom ports and developing a unique connection method.

15 years ago, there was even no voltage parameter label on the power supply, and it was necessary to ensure that the voltage and power of the power supply were correct before charging. Today, whether you are at home, at work, or outdoors, you can directly plug in the power to charge your phone. You can also plug your phone into any computer and display photos and more on the computer screen, thanks to standardized connectors.

However, not all USB chargers have the same functionality, as wall USB chargers are more robust than other chargers; The USB socket of a laptop is more powerful than other functions, and even after shutting down, it can continue to charge the phone.

Isn't a USB charger amazing? Today we will learn how USB power supplies work.

Existing USB interface types:　　

USB 1.0, 2.0, 3.0, and 3.1, as well as new USB C interfaces!

Among them, USB 3.0 is a common USB interface, which is commonly used in daily computer hosts, smartphones, tablets, and cameras. The power supply flows from the main device, such as charging a mobile phone; But data can be transmitted in both directions, for example, computers can copy data files from mobile phones.

The regular USB 1.0 and USB 2.0 interfaces have four pins and four wires; Internal pins carry data (D+and D -), while external pins provide 5V power supply. USB 3.0 has added 5 rows of pins, resulting in 9 pins. Under normal current, USB 3.0 can be compatible with USB 1.0 and USB 2.0, but USB 1.0 and USB 2.0 cannot be used in USB 3.0. And USB C can achieve twice or even higher power than USB 3.0.

The speed of USB charging depends on the power supply and the device itself. For example, the USB 3.0 interface can charge USB 2.0 interface devices, but if the device itself does not handle the design of increasing power, it will still obtain power according to the device's own rate. It depends on the iPhone device to charge the iPhone with an iPad charger.