Overview

CPAM (Common Power Analysis Methodology for microprocessors) is a design methodology and tool set for the highly detailed analysis of power as well as on-chip noise and reliability of the power distribution network of hierarchically designed, high-performance microprocessors. By performing circuit simulations on an extracted, layout view of a microprocessor design, instantaneous currents are calculated and summed over simulated operational cycles. On-chip decoupling capacitors as well as parasitic, wire-to-wire, and intrinsic device capacitances are taken into account. From these currents, a picture of the instantaneous power requirements as well as on-chip power supply noise is calculated. By incorporating accurate electrical models of the chip package (including inductance), a true picture of variations of supply voltage and on-chip heating can be obtained. This information is essential for the evaluation of dI/dt and chip contact (C4) placement. From the simulations, we are also able to calculate current densities in every power supply wire segment, and level-to-level via, to ensure that the design is free of long-term reliability concerns such as electromigration.