High-frequency modelling of surface-mount power inductor used in switching DC-DC converters

A lumped-element model of a 72-nH surface-mount power inductor used in high-frequency DC-DC converters is presented. The model parameters are optimized to fit the measured impedance characteristics. Two different topologies of the characterization set-up are used: the first one to extract the model and the second to validate its impedance characteristics up to 300 MHz. The extracted model demonstrates the impact of skin effect on the impedance characteristics. The model consists of frequency-independent components. The extracted model allows accurate estimation of AC power losses of the inductor and power efficiency of a DC-DC converter.