To thin a charging part without damaging the function of the high-frequency oscillating circuit of the charging part especially, by arranging each electronic component which constitutes the high-frequency oscillating circuit, on the same board surface with a charging coil.

Each electronic component is arranged on the same board surface of a circuit board 21, and an oscillating coil 23 is arranged so as to adjoin the peripheral part of a charging coil to obtain sufficient coupling with the charging coil 22. Other electronic components which form a high-frequency oscillating circuit excluding the oscillating coil 23 is arranged and mounted inside the charging coil 22. Consequently, a charging part comes to have a thickness in the extent of the sum of the thickness of the circuit board 21 and the height of the charging coil 22 in the aggregate, and the thickness is reduced approximately to a half of that of a conventional one. Besides, further thinning becomes feasible by using a surface mounting component for each electronic component.