IC power delivery: Voltage regulation and conversion, system-level cooptimization and technology implications

TLDR: A systematic design analysis on power delivery networks that incorporate Buck Converters and on-chip Low-Dropout voltage regulators for the entire chip power supply shows significant performance improvements in terms of achievable area overhead, supply noise and power efficiency.

Abstract: Modern IC power delivery systems encompass large on-chip passive power grids and active on-chip or off-chip voltage converters and regulators. While there exists little work targeting on holistic design of such complex IC subsystems, the optimal system-level design of power delivery is critical for achieving power integrity and power efficiency. In this article, we conduct a systematic design analysis on power delivery networks that incorporate Buck Converters (BCs) and on-chip Low-Dropout voltage regulators (LDOs) for the entire chip power supply. The electrical interactions between active voltage converters, regulators as well as passive power grids and their influence on key system design specifications are analyzed comprehensively. With the derived design insights, the system-level codesign of a complete power delivery network is facilitated by a proposed automatic optimization flow in which key design parameters of buck converters and on-chip LDOs as well as on-chip decoupling capacitance are jointly optimized. The experimental results demonstrate significant performance improvements resulted from the proposed system cooptimization in terms of achievable area overhead, supply noise and power efficiency. Impacts of different decoupling capacitance technologies are also investigated.