Abstract: A charge pump device includes a charge pump circuit, for generating an output voltage according to a driving signal, a comparing circuit, for generating a comparison result according to the output voltage and a reference voltage, a detecting circuit, for detecting a frequency range of a ripple of the output voltage according to the comparison result and generating a detection result, and a driving stage, for generating the driving signal according to the comparison result, and adjusting a driving capability corresponding to the driving signal according to the detection result.