A phase-control power controller that converts a line voltage to an RMS load voltage includes a phase-control circuit connected to the line and load terminals and having an RC network that clips the load voltage. A load sensing circuit is connected across the load terminals that senses the load voltage and provides a DC signal that is related to an RMS load voltage. A comparison circuit is connected to the phase-control circuit and the load sensing circuit and compares the DC signal to a reference and adjusts a resistance of the RC network in response to the comparison of the DC signal to the reference to control the RMS load voltage.