An integrated structure of passive elements in an LLC resonance converter realized by flexible circuit boards includes a closed magnetic circuit formed by first and second magnetic cores, a tubular, double-sided, flexible circuit board, tubular magnetic-material layer and tubular, single-sided, flexible circuit board. A wireless signal switching circuit 1 has a signal route switch 20 of a F2 or F3 transmission and reception system, a signal route switching circuit 30 of an F1 or UMTS transmission and reception system having a diplexer 31, and a 90 degree phase rotation circuit 40. The thermal schematic may be obtained by extracting the thermal RC circuits, identifying corresponding electrical circuit components that correspond to the extracted thermal RC circuits, and importing the thermal RC circuits into the electrical schematic so that the electrical and thermal schematics have the same nodes.