A bias supply, a method of communicating data across an isolation barrier and a power supply are provided herein. In one embodiment, the bias supply includes: (1) a bias supply transformer having a primary winding inductively coupled to a secondary winding across an isolation barrier, (2) a controller configured to direct operation of the bias supply and (3) bias voltage manipulating circuitry, coupled to an input of the controller, configured to receive primary data and based thereon alter a secondary bias output voltage of the secondary winding between defined voltage levels by varying a voltage provided to the controller, the controller and the bias voltage manipulating circuitry located on the primary side.