Disclosed is a power-efficient multi-mode charge pump. The charge pump comprises a first pumping circuit that provides at least one output voltage produced by a discharge sequence of a shared flyback capacitor. The charge pump also comprises a second pumping circuit that provides a plurality of output voltages produced by a corresponding plurality of discharge sequences of the shared flyback capacitor. The charge pump may include a transition circuit to selectably enable the first pumping circuit or the second pumping circuit. In one embodiment, the first pumping circuit may employ a two-phase discharge sequence. In another embodiment, the second pumping circuit may employ a three-phase plurality of discharge sequences. A related method is also disclosed.