Patent ID: 8207635

Claim:
An electric circuit electrically coupled to and for communicating over a line, the electric circuit comprising: a processor; a switch electrically coupled in series with a load, the switch and the load in series between first and second conductors, the first and second conductors comprising the line, wherein the line provides direct current power to the load over the first and second conductors of the line; and a resistive element electrically coupled in parallel with the switch and in series with the load; wherein the switch is configured to short circuit the resistive element when closed such that a voltage on the line varies between a first voltage level and a second voltage level when the switch is opened and closed; wherein the voltage on the line is an electric potential difference between the first and second conductors; wherein the line provides the direct current power to the load when the switch is opened and when the switch is closed; wherein the processor is configured to direct the switch to vary the voltage on the line between the first voltage level and the second voltage level, the variation of the voltage on the line indicative of data transmitted over the line; wherein the direct current power provided to the load over the first and second conductors of the line increases from a first power level to a second power level based on the data indicated by the variation of the voltage on the line between the first voltage level and the second voltage level; and wherein the voltage on the line varies between a third voltage level and a fourth voltage level when the switch is opened and closed at the second power level.