Comparison of electrical and electromagnetic properties of a planar inductor

This paper compares the electromagnetic and electrical properties of a planar inductor used in a low-profile organic light-emitting diode (OLED) driver. A luminary consists of the OLED cell and its driver which uses a planar inductor. The proximity of the OLED cell and the constrained area makes the planar inductor lossy. The planar inductor represents a loop antenna and a main source of radiated emissions of the driver. The properties of the planar inductor are analysed w.r.t. the quality factor and the magnetic moment. The analysis uses a two-level experiment based on EM simulations to explore the geometrical parameters of the inductor. The experiment shows that the track width and the fill-ratio of the inductor have the largest effect on its properties. It is concluded that a planar inductor which introduces minimum power losses and radiated emissions to the OLED driver needs to be optimized w.r.t. the track width and the fill-ratio.