Modeling and Analysis of Power Distribution Networks for Gigabit Applications

As the operating frequency of digital systems increases and voltage swing decreases, it becomes increasingly important to accurately characterize and analyze power distribution networks (PDN). This paper presents the modeling, simulation, and measurement of a PDN in a high-speed FR4 printed circuit board (PCB) designed for chip-to-chip communication at a data rate of 3.2 Gbps and above. The test board consists of two transceiver chips placed on wirebond plastic ball grid array (PBGA) packages. The applied analysis method is a hybrid technique that combines the interactions of the power planes, interconnects, and the nonlinear drivers. The power planes and interconnects are modeled using the transmission matrix method (TMM) and rational interpolation, respectively. Then macro modeling is applied to generate reduced-order models to efficiently analyze the whole system including the nonlinear drivers using conventional circuit simulation tools such as SPICE. The transfer characteristics of the power planes are calculated and the effects of the decoupling capacitors and power supply noise are studied. The simulation results are also correlated with measurement data to verify the validity of the method.