In the process of electronic system whose clock frequency increasingly rises, signal integrity issues come out gradually such as incorrect timing sequence and incorrect reflection of transmission lines, badly influencing the normal running of circuit system. Furthermore, traces on PCB become so compact that crosstalk noise will be generated and signal transmission obtains bad effect. For high-speed digital-analog mixed circuitry, according to the practical situation of signal running, PCB design should be reasonably implemented to solve signal integrity issues, to constantly increase the quality of signal transmission and to provide important information sources for the development of different industries and fields.