A low-cost, wide input range, DC-DC voltage-switching converter regulator device for supplying power to various components in an automotive application includes two pairs of serialized switch elements for controlling separate Boost and Buck Modes each through a respective one of said pairs. In particular, the converter regulator device is arranged for under control of a driving voltage below a first threshold voltage outputting a negligible output current, in a Buck-Mode under control of a driving voltage above a second threshold voltage outputting a Buck-Mode flat current level through alternating and mutually opposing conducting states of the first switch elements, and in a Boost-Mode under control of a driving voltage between the first and second thresholds outputting a Boost-Mode flat current level that is substantially lower than the Buck-Mode current level through driving via the inductor a medial tap of serialized second switch elements of which one terminal tap constitutes an output terminal of the converter.