A driver for a DC-to-DC converter that may utilize a flyback or buck-boost converter circuit. The driver includes a driver circuit and an interface circuit. The interface circuit has a sensor sensing an input voltage from a DC supply and generating a sensor signal to a driver selector. The driver selector compares the sensor signal to a comparison voltage to determine the type of converter circuit and then transmits a selector signal to a driver circuit where it is used to control one or more of the components of the driver circuit, such as the logic circuit which is used for driving the converter to regulate the converter output. The sensor includes a sense resistor along with a current-sense amplifier, which is adapted for connection to a high side or a low side of a power supply while still producing a substantially equivalent output voltage or sensor signal.