Optimization of power integrity and signal integrity based on a field-circuit combined method

Since lumped circuit elements can't reflect effects of distributed parameters in the printed circuit board (PCB), this article uses electrometric computing software to calculate S parameters of the PCB and converts them into circuit models to perform field-circuit combined simulations, improving accuracy of power integrity (PI) and signal integrity (SI) analyze. Based on that, PCB decoupling network is analyzed using decoupling current and target impendence, and by optimizing PCB stack and drilling via holes at pads, decoupling network gets lower impendence, higher decoupling current and more suitable for high density designs. Moreover, characteristic impendence matching is achieved by adjustment of PCB stack. Simulation results show power supply ripple after optimization is reduced into desired level and optimized signal transmission is normal thus PI and SI are met.