Abstract: A DC power circuit for a electrostatic chuck adapted for use in a plasma etching system is disclosed. The power circuit receives an input that reflects a voltage bias on the workpiece caused by the application of an RF signal for creating the plasma. A DC power supply outputs a differential voltage that is balanced by inputting the voltage bias to a common reference node. The balanced DC output voltages are then presented to two electrodes of the ESC to create a clamping force securing the workpiece to the chuck at a lower voltage than would otherwise be applied in the absence of the bias feedback.