High frequency characterisation of multilayer PCBs

Electronic circuits are complex and are expected to operate at very high frequencies. The circuit performance mainly depends on the type of components used and routing of the interconnections. As the frequency of operation increases, the circuit performance depends heavily on the interconnection net. With the advent of multilayer PCB technology, one can have many interconnection planes along with VCC and ground planes. This multilayer technique reduces the interconnect length considerably. However, this increases the interconnect density and thereby decreases the interconductor spacing. This gives rise to the possible electromagnetic interference which in turn causes crosstalk voltage. We present a powerful technique to characterise multilayer PCBs. The electrical representative model parameters of the multilayer interconnections are estimated using the versatile finite element method. Time-domain analysis of these multilayer multiconductor (MLMC) structures has been performed using "subcircuit method".