Wireless charger with combined electric radiation shielding and capacitive sensing functions

A wireless charger for charging an electronic device with a second coil, comprising:

• a charging module, comprising a first coil electromagnetically coupled to the second coil, a placing area for the electronic device to be placed on opposite to the first coil, and a comb-shaped shielding located between the placing area and the first coil;
• a capacitive sensor, which is connected to the comb-shaped shielding to detect the capacitance varient between the comb-shaped shielding and the environment;
• and
• a control unit, which is connected to the comb-shaped shielding and the capacitive sensor and records the capacitance varient;
• wherein, when the capacitance varient exceeds a predefined threshold, the control unit sends a ping signal to the electronic device, and if the electronic device responds, the control unit switches the charging module from a standby mode to a charging mode to wireless charge the electronic device and switches the comb-shaped shielding to be connected to a ground.