A Frequency-Dependent Target Impedance Method Fulfilling Both Average and Dynamic Voltage Drop Constraints

Abstract

Target impedance has been playing a critical role in guiding robust power delivery network (PDN) design. However, traditional methodology has difficulty in associating time domain behavior, such as current profile and voltage drop, with frequency domain PDN impedance. Also, average voltage drop is not explicitly considered in the methodology. These two problems may cause under- or over-designed PDN. This paper proposes a novel frequency-dependent target impedance methodology. The proposed methodology first determines the target impedance shape from the given constraints of average and dynamic voltage drops and exploits a concept of magnitude equivalent frequency (MEF) to bridge the time domain behavior and frequency domain target impedance. Experiment results show that the proposed frequency-dependent target impedance tightly satisfies the given constraints of average and dynamic voltage drops.