Adaptive inductive power supply with communication

A contactless power supply for inductively providing power to a remote device comprising: an inverter, the inverter having a duty cycle and an operating frequency; a resonant circuit coupled to the inverter, the resonant circuit having a primary for transferring power to the remote device by an inductive coupling, wherein part of the primary is a communication coil configured to transfer information with the remote device; a power source coupled to the inverter, the power source having a rail voltage; and a controller coupled to the communication coil, wherein the controller is programmed to communicate with the remote device via the communication coil.