Certain aspects of the present disclosure are generally directed to apparatus and techniques for protecting electronic devices that may be prone to damage by wireless charging fields. For example, the apparatus may include a wireless charging circuit configured to selectively generate a wireless charging field and an impedance detection circuit coupled to the wireless charging circuit and configured to detect an impedance change corresponding to the wireless charging field. In this case, a proximity detection circuit may selectively detect proximity of one or more electronic devices that are prone to damage by the wireless charging circuit. In some aspects, detecting the proximity of the one or more electronic devices is activated based on detecting the impedance change, and wherein generating the wireless charging field comprises reducing a transmit power of the wireless charging field based on detecting the impedance change.