USB- is the abbreviation of English UniversalSerialBUS (Universal Serial Bus), and its Chinese abbreviation is "tong serial line"; it supports plug-and-play and hot-swappable functions of the device. USB was jointly proposed and formulated by Intel, NEC, Compaq, DEC, IBM (, Microsoft, NorthernTelecom, etc.) in 1994. The USBV0.7 version was published on November 11, 1994, and it has now been developed to version 3.1. 。USB has the advantages of fast transmission speed, convenient use, support for hot plugging, flexible connection, independent power supply, etc.; and USB certification is also called USB-IF certification, which is a voluntary iconic promoted by USB Implementers Forum (USB-IF) Certification.
USB standard type
USB2.0 standard types: USB Type A male, Type A female; USB Type B male, Type B female; Mini USB male, female; Micro USB male, female;
USB3.0 standard type: USB type A male, type A female; USB type B male, type B female; Micro USB male, female;
USB3.1 standard type: Type C male, Type C female;
USB2.0 standard type: USB A to B, USB to MiniB, USB A to MicroB
USB3.0 standard type: USB A to A, USB to B, USB A to MicroB
USB3.1 standard type: Type C to Type C
USB-IF certification test content
Certification tests for USB peripherals can be divided into three categories. The first is the electrical characteristic test, which verifies the signal quality of the product under different application architectures. Next is the functional test, which is used to check higher-level product details, such as the degree of support for standard requirements and device enumeration functions. The latter is the product interoperability test, which is used to determine the interaction between the tested product and other USB devices.
Why do we need USB certification
USB certification is generally based on the requirements of the client. The USB functions used on high-end products generally need to apply for USB certification. USB products can use the USB logo and obtain the TID number of the USB product after applying for the association certification. If USB products want to use this logo and have a TID number, they must first apply to the USB Association to become their member, and only after they have membership qualifications can they apply for component certification.