ABSTRACT
PCB is depicted2 consisting of a number of pre-impregnated (prepreg) layers (a partly cured mix of resin and glass fiber) and fully cured prepreg layers with copper foil attached to form the cores (laminates) carrying signals and providing power and ground planes. The complete PCB is
formed by heating the entire assembly under pressure so that the partially cured prepreg flows and bonds to the laminates. Vias are also provided to carry signals from one layer to another. Each of these components carries high-frequency signals and thus is effectively an unwanted antenna receiving and dispersing EM radiation to its neighbors and beyond. The problem is particularly acute with the current and projected clock rates of several gigahertz. One of the objectives of good EMC design is the minimization of emission at source, hence the design of chips must be subject to the same EMC discipline as any other circuit component. The reverse is also true, i.e., the EMC behavior affects signal integrity. A check list of the items to watch for in EMC and SI is shown below.3
