Effect of the Tolerances in Multi-Phase DC-DC Converters

Multiphase technique is being used in several DC-DC applications such as VRM and automotive. The use of a high number of phases provides several advantages being the reduction of input and output filters one of the most important. However, due to the tolerances of the components (semiconductors and inductors) these advantages are limited. The purpose of this paper is to evaluate the effect of tolerances in the inductance on the output current and voltage ripple. Also, it is shown how the digital control may help to reduce drastically this problem. Experiments are included in the paper