Patent ID: 8324538

Claim:
A method for sourcing a resistive load, the method comprising: generating a pulse width modulation (PWM) control signal; controlling a switch based upon the PWM control signal, wherein the switch sources the resistive load from a power source; modifying a duty factor of the switch in response to the PWM control signal to reduce a power drawn by the resistive load to a power limit in response to the power drawn by the resistive load exceeding the power limit defined by a slope-intercept curve; providing a first resistor defined by a first resistance with a sensed current corresponding to the current drawn by the resistive load; providing a second resistor defined by a second resistance with a sensed voltage corresponding to the input voltage from the resistive load; and wherein the slope of the slope-intercept curve is defined by a ratio between the first resistance of the first resistor and the second resistance of the second resistor.