The objective of the A4WP specification is to match real-world charging situations as closely as possible, while minimizing the difficulty in building products that conform to them. A4WP will publish a specification to include requirements for the transmitter and receiver, mutual coupling and mutual inductance, leaving most options open to members’ designers.

Designers can specify and source their own out-of-band radios, power amplifiers, DC-to-DC converters, rectifiers, microprocessors – discrete or integrated – and assemble them as they require.

As long as the components conform to the specification, they can be of any topology.

The specification reserves only the interfaces and model of transmitter resonator to be used in the system