An electronic ballast to supply automotive HID lamps in a low frequency square waveform

This paper presents an electronic ballast to supply a 35 W high intensity discharge (HID) xenon lamp for automotive applications. The ballast consists on a bidirectional flyback operating in discontinuous conduction mode (DCM) and an igniter circuit. The converter supplies the lamp in a 400 Hz square waveform and the igniter is responsible for providing the necessary voltage for lamp start up. The purpose of this work is to supply the xenon lamp from a 12 V battery with a reduced number of components, decreasing the system final costs without penalty the reliability. Some experimental results are presented to validate the proposed ballast behavior.