All-in-one method for wireless connectivity and contactless battery charging of small wearables

A wireless communication method that comprises:

• coupling an antenna coil to a wireless charging module to charge a battery;
• coupling the antenna coil to an NFC (near field communications) module, the NFC module:
• receiving a query signal;
• providing a tag response signal;
• and
• receiving a command signal to set at least one parameter value affecting rendering of an audio stream;
• and
• coupling the antenna coil to an NFMI (near field magnetic induction) module to send or receive the audio stream.

A hearing aid that comprises:

• a microphone;
• a speaker;
• a battery;
• an antenna coil around a ferrite element;
• a controller powered by the battery, wherein the controller filters and amplifies sound received via the microphone for playback via the speaker, and wherein the controller includes:
• a wireless charging module coupled to the antenna coil to harvest wireless power for charging the battery;
• an NFC (near field communications) module coupled to the antenna coil to receive a query signal and provide a tag response signal, wherein the NFC module further reports parameter values and accepts new parameter values for operation as said hearing aid;
• and
• an NFMI (near field magnetic induction) module coupled to the antenna coil to exchange audio streams with a second hearing aid in an opposite ear,
• wherein the controller selectively enables only one of the wireless charging, NFC, and NFMI modules at a time by setting an adjustable capacitance in series or parallel with said antenna coil to provide a tunable resonant frequency, wherein the controller adjusts the resonant frequency to a value suitable for the selected one of said wireless charging, NFC, and NFMI modules.