Normalized Inductance Modeling for Ferrite Power Inductor Families This paper discusses a normalized inductance modeling approach for Ferrite Power Inductors (FPIs), aimed at facilitating the analysis of inductors performances and their selection in SwitchMode Power Supply (SMPS) design. A normalized temperatureindependent inductance versus current curve is proposed, to describe the saturation behavior of an entire family of inductors with different nominal inductances, made of different winding turns on the same magnetic core. A Normalized Operating Area (NOA) of the inductor family is consequently derived, allowing a quick identification of the normalized ranges of average inductor current and voltsecond integral associated to the desired levels of a given performance of interest (e.g., the peaktopeak inductor current ripple). By means of the NOA, it is possible to obtain the Real Operating Area (ROA) of each inductor, without performing additional simulations. Examples of application of the proposed modeling approach are provided for two FPI families, with shielded and unshielded magnetic cores of different ferrite materials.

A lowcost online estimator for switchmode power supplies with saturating ferritecore inductors Ferritecore inductors are largely used in switchmode power supplies (SMPSs) and can be fruitfully exploited also when working in partial saturation. Several behavioral models have been recently proposed to represent both inductance and power losses in saturation conditions. In this paper we exploit this kind of models for estimating online relevant features of the SMPS inductor, such as current ripple and power loss, which are difficult to monitor through acquisition of easilymeasurable quantities only. The method works at electrical steadystate, but is able to follow the thermal transients. Models are implemented on a lowcost microcontroller and tests are performed on a boost converter, for different operating conditions.