Signal Integrity Simulation And Analysis Of High-speed Interconnect

In the development process of the high-speed digital circuit, signal intergrity (SI) problemsgradually draw people’s attention, and become the essential part of the design. Especially in thePCB design stage, the most constraints are based on SI analysis. Depth understanding of theknowledge about SI, contributes to the more realistic constraints, and is also a necessary conditionfor the SI analysis. In order to make the PCB design successful all at once, searching the relativelyaccurate simulation model and using the reasonable methods on analysis, has been become a basicskill for the PCB engineers.Broadly speaking, SI includes all the problems about the signal quality or delay due to theinterconnection, power and device, involving the knowledge of electromagnetic fields, microwave,analog circuits, digital circuits, physical material and so on. SI designers usually have a good skillof using the knowledge and solving the problems. The basic theory of SI primarily includestransmission line, signal loop, timing, reflection, crosstalk, as well as Power Integrity. The basictheory is the starting point for the design.The traditional design approach of PCB is trial and error, which has long cycle and high cost.In order to shorten the cycle, in this paper we use a new design thinking, and make use of the meansof simulation and analysis about the high-speed interconnection part in the example. Among this,the impedance calculation, the simulation of the reflection and crosstalk are the fundamental basisfor the constraint rules. The circuit timing is key to ensure the normal use of the system, so thecalculation of timing margin is essential. The method about the target impedance is a reliable choicefor the network design of Power Intergrity. By the selection and installation of the capacitors we canplan for the PDN system, and the simulation of the target impedance verifies the effectiveness. Butwe must know that the design of SI doesn’t means the simulation of SI.The SI design is a process ofthe balance in various measures.The thinking about the SI analysis of the high-speed interconnection in this paper, can reliablydesign ciruit boards, increase the chances of success and reduce the cost. The example in this paperis a typical instance in the field of the high-speed interconnection, which has the guiding sense tothe PCB design.