Matrix integrated magnetics (MIM) for low voltage, interleaved DC-DC converters

In this paper, we present the application of the matrix integrated magnetics (MIM) core to an interleaved current doubler rectifier (ICDR) controlled according to the symmetric modulation scheme. Detailed modeling and design equations that describe the effect, due to magnetic coupling, of integrating the magnetics of two CDRs on a single core structure on the currents and fluxes are presented. Comparative analyses between an ICDR using a MIM core and two EI-cores and a CDR using a single EI-core for a 48 V-3.3 V/100 W DC-DC converter design example show that the MIM core can be effectively used for the ICDR providing substantial benefits over a dual EI-18 core solution or a single EI-22 core. Preliminary experimental results from a 100 W, 48 V-3.3 V ICDR laboratory prototype demonstrating the validity of the MIM core structure for this application are presented.