Technique Advantages for Planar Transformers in High Frequency Switching Mode Power Supplies

The main trend for SMPS development is high power density. In order to achieve it, improving the power density of the magnetic components in SMPS is a important techniques. Since planar transformers have advantages that improve the SMPS performance, their use is growing in the last years. Some of the high frequency parasitic parameters can be drastically reduced due to their planar geometry and the proximity of the winding. A study of different structures and winding strategies using a standard procedure to build planar transformer is presented. This standard method makes easier and cheaper the transformer construction. Finally, the design guidelines and some experimental results ahout the different parameters between the traditional transformer and planar transformer are also included.