Improved distributed model for capacitors in high-performance packages

Time-domain and frequency-domain measurements show that a simple lumped RLC model for a multilayer ceramic capacitor is inadequate, overestimating high-frequency impedance by a factor of five. A lossy transmission-line model works better, and is improved by placing incremental resistance in series with the incremental capacitance. Refinements of this model are developed based on time-domain step-response measurements and on frequency-domain impedance measurements. Better packaging to reduce series inductance is discussed.