Abstract: Electrical activation of an arc lamp is accomplished by a plurality of circuits, each of which has a boost topology including a capacitor and a charging circuit for charging the capacitor by a series of current pulses. One of the circuits is an igniter circuit and includes a transformer to convert voltage from a relatively low voltage supply to a relatively high voltage for striking an arc within the lamp. A second of the circuits provides for a steady flow of current to maintain the arc after completion of ignition of the arc. The second circuit is protected from the high voltage of the first circuit by a saturable reactor connected in series between the second circuit and the arc lamp.