Maintenance of smart phones, principles and maintenance methods of NOK, MOT, Samsung and Sony Ericsson new phones. Explain the maintenance and detailed circuits of eight chipsets of domestic machines, miscellaneous brands and domestic machines. In particular, explain the methods of removing glue from various sealed chips, explain the maintenance skills, and cultivate students' correct maintenance ideas from the depth and breadth. Pay attention to cultivating students' self-study ability, so that they can repair any mobile phone without drawings and accessories. I have friends who studied it before the national vocational qualification certificate and the hardware engineer certification certificate issued by the Ministry of Industry and Information Technology, and now they have opened stores. I really envy you. . . . . . .