IV-overlap power losses play an important role in the overall conversion efficiency of a switched-inductor power supply, which is why a clear understanding of its mechanism is necessary. This paper proposes an insightful model with device-based expressions. The model accounts for the non-linear and dynamic behavior of gate capacitances in switching MOSFETs and reverse-recovery effects produced by interconnected diodes, which are largely absent in the state of the art. Calculated and simulated overlap losses with and without reverse recovery are within ±10%