Short-range wireless communication device

A short-range wireless communication device having a power-receiving function, the short-range wireless communication device comprising:

• a power-receiving coil configured for both power reception in wireless power supply utilizing short-range radio and reception in wireless data communication utilizing the short-range radio;
• a power-receiving resonance circuit in which the power-receiving coil and two or more resonance capacitors configure a resonance circuit;
• and
• a wireless communication circuit and a load circuit each of which is electrically connected with the power-receiving resonance circuit, the load circuit being configured to perform an operation using electric power, and the load circuit includes a voltage conversion circuit, a charging circuit, a secondary battery, a voltage conversion circuit, a charge control circuit and a discharge control circuit, wherein
• the power-receiving resonance circuit includes
• a receiving circuit configured to supply a communication voltage to the wireless communication circuit from the power-receiving coil, and
• a power-receiving circuit configured to supply a power-reception current to the load circuit from the power-receiving coil,
• the receiving circuit and the power-receiving circuit have a common circuit portion,
• the two or more resonance capacitors include a first resonance capacitor and a second resonance capacitor in the common circuit portion,
• the first resonance capacitor is electrically connected in parallel to the power-receiving coil to configure a parallel resonance circuit together with the power-receiving coil, and the parallel resonance circuit is configured to perform a parallel resonance operation at a frequency of an alternating magnetic field of an outside,
• the second resonance capacitor is electrically connected in series to the power-receiving coil to configure a parallel series resonance circuit together with the power-receiving coil and the first resonance capacitor, and the parallel series resonance circuit is configured to perform a parallel series resonance operation at the frequency of the alternating magnetic field of the outside, and
• with an impedance adjusting circuit including the parallel resonance circuit and the parallel series resonance circuit,
• a wireless-communication output impedance of the receiving circuit with respect to the wireless communication circuit at a communication frequency is higher than or equal to a first predetermined value for realizing load modulation, and
• a power-reception output impedance of the power-receiving circuit with respect to the load circuit at a power-receiving frequency is lower than or equal to a second predetermined value for realizing power supply, and
• operations of both of the receiving circuit and the power-receiving circuit are performed in parallel.