A hybrid cavity and parallel-plate PEEC method for analysis of complex power net area fills, and a tool development for peak distortion analysis

"Modern ASICs and FPGAs are becoming more and more dense, which is causing an increasing demand of the current draw from the power distribution network (PDN). And one of the main design objectives of a power distribution network is to reduce the voltage noise ripple below a specified allowable limit. Although the target impedance is a commonly used criterion in most PDN designs, it may not be efficient because it's usually rather pessimistic. Herein a time domain voltage ripple decomposition approach is proposed to avoid overdesign as well as provide design guidance to PI engineers. Based on a physics-based circuit model for PDN and a switching current generator including both high frequency switching and low frequency power gating, the total voltage ripple can be divided into several components. Each component will have a one-to-one correspondence to the real PDN geometry. Thus design curves can also be derived, which can guide PI engineers when making design decisions.Peak distortion analysis (PDA) is commonly used to find the worst-case eye diagram and data pattern. Compared to traditional long transient simulations, PDA can significantly reduce the computation time by only taking into consideration the worst case. Generally PDA is based on a superposition technique with a single bit response (SBR), which requires the system to be linear time invariant (LTI) or can be well approximated as an LTI system. SBR is no longer applicable for systems which have different rising and falling edge responses due to asymmetric I/O design or mismatches between pull-up and pull-down drivers. Also sometimes the nonlinearity can extend beyond the edge transitions which can result from the voltage noise on the power distribution network (PDN). Herein PDA based on the superposition of multiple edge responses (MER) is proposed to account for a non-LTI system as well as asymmetric rising and falling edges"--Abstract, page iii.