a dc - dc converter for converting an input power to generate a first power and for outputting the first power to a first output terminal , the dc - dc converter including : a resistor unit for electrically connecting a set resistor to the first output terminal when the voltage of input power is in a specific range , and a mobile communication terminal using the same . here , the dc - dc converter is capable of reducing or removing a pulse skip mode by increasing a load of an output end if it is determined that the voltage of the input power is in the specific range , by sensing the input power .