Development of a universal contactless charger for handheld devices

The purpose of this paper is to design and implement a universal contactless charger for handheld device by means of electromagnetic coupling induction related applications. Through coil coupling induction, contactless power transmission system is able to supply power to the secondary side with high safety and low repair rate features. However, this paper discusses PCB (Printed Circuit Board) and a spiral-type induction coil used as a coupling induction device for the contactless charging system. With the design proposed in this paper, the size of regular counting induction devices can be greatly reduced. By changing the geometric shape and location of coupling coil, the relationship and changing conditions of respective parameters and coupling coefficients can be obtained and analyzed to serve as references for future designs. Therefore, in conjunction with theoretic and actual design guidelines, sequential studies will be conducted. Finally, contactless mobile phone charger with rated 4.2V, 800 mA is completed to validate its function.