In the emerging automobile fields, head light plays a vital role in the aspect of safety. Only a fraction of total power from the battery should be utilized for its operation. In conventional lighting technologies, head light consumes high power, less efficient and also struggles for the variation of input voltage. This paper proposes a simple modified half bridge converter (MHBC) design for automotive lighting applications. The converter has two switches in which duty cycle of one switch is controlled and other one remains fixed at a particular duty cycle. This reduces the control complexity. In addition, the converter is capable of operating in buck and boost mode which is much essential for source variation. The parasitic state space model of the converter is derived using state averaging technique, which helps in obtaining the realistic operation of the converter. Stability analysis is carried out for the proposed model, which is in line with the practical model. The obtained frequency response curve helps in calculating the stable operating range of the duty cycle. The conduction and switching losses are calculated to get the efficiency of the system. The simulation of the proposed system is performed in PSIM software and a prototype model is realized with 21 W power rating. The performance of the converter is tested under wide input voltage variation (10 to 50 V) for a 30 V/0.7A light-emitting diode string. © 2021 John Wiley & Sons Ltd