Power integrity analysis for high performance design

Power Integrity and its influence on system performance have become very important in deep sub-micrometer technology design. A robust power distribution network (PDN) is required to provide power within specified tolerance to ensure reliable operation of circuits in a system. Modeling a good PDN and performing power integrity analysis is very essential with low voltage, high transient current, high speed and high density designs. In this paper, we have discussed AC and DC analysis methodology to achieve better Power Integrity (PI). This analysis methodology provides emphasis on pre-route PI analysis. The pre-route PI analysis includes estimation of plane dimension, plane resistance/inductance, via resistance, via dimension, appropriate layer for routing, target impedance, decoupling capacitor requirements and capacitor mounting inductance. The parameters of PDN elements derived analytically are modeled as an equivalent circuit in SPICE to analyze the PDN response. The post route PI analysis performed using PI simulation matches closely with the results obtained during pre-route analysis. This analysis has been validated using actual measurement in the system in terms of DC voltage drop, ripple and transient response.