Analysis And Applications Of High-speed Signal Integrity For The System Of Vehicle-mounted Video

As technology and economic level continuously improved, the system of vehicle-mounted video has gradually integrated into people’s daily life, and it becomes the essential condition when people buy cars. However as the working frequency of the vehicle electronics becomes higher and the edge of the signal becomes increasingly steeper, a larger number of interconnects can not be used as the ideal transmission line. It makes the signal integrity problems become more complex and has tremendous impact on the stability of the system. Based on the investigation on the foundation theory of the signal integrity and the existing research results, this dissertation puts forward some methods which can make the signal integrity to be guaranteed. The main research work is as follows:(1) Among many factors which can cause signal integrity problems, signal reflection and crosstalk are two main aspects, which always disturbs the designers. This dissertation introduces the mechanism from the theoretical point of view, and summarizes the common methods of suppressing reflection and crosstalk, which is matching the characteristic impedance of the transmission line. Then this dissertation analysis series termination and parallel termination based on the existing theory and puts forward one method which is comprehensive termination. Simulation results show that compared with series termination and parallel termination, the comprehensive termination eliminates the first reflection and the second reflection at the same time, and overshoot and undershoot are almost been eliminated, the rise time of the signal has been delayed,as well.(2) In the process of the research, we combine with the advantages of LVDS which compared with the single-ended transmission signal, such as strong anti-interference capability, timing position accurately and so on. Based on the foundation of jumping a resistor at the ends of LVDS’s differential pair to achieve termination matching, this dissertation puts forward that add to T-improved network at the end of the differential pair which can match the differential impedance and common impedance. Compared with the ends of LVDS’s differential pair without impedance matching, the results of simulation shows that overshoot and ringing gets obviously improvement, which ensuring the signal integrity.(3) With the development of LCD,the requirements of storing data are also increased. On the foundation of introducing the principle and structure of DDR3, the effects of these models on the eye diagram are simulated, the package and vias are of largest significance which can cause signal integrity of DDR3. The fly-by structure is found to be crucial and capacitance compensation should be employed for achieving impedance matching. Compared with the structure without capacitance compensation, simulation results show the reflected signal can be reduced by 10%-15%.