DC-DC converting apparatus

A DC-DC converting apparatus including a multi-phase controller and power channels is disclosed. Each power channel includes a first capacitor, a second capacitor, an output unit, a converting unit, a first inductor, a second inductor and a first switch ~ a fourth switch. The first capacitor and the second capacitor are coupled between an input voltage and ground. The first switch and the second switch are coupled between input voltage and ground. The converting unit has a first terminal coupled between the first switch and the second switch, a second terminal coupled between the first capacitor and the second capacitor, a third terminal coupled between third switch and the first inductor, and a fourth terminal coupled between the fourth switch and the second inductor. In a timing control, when the multi-phase controller conducts the first switch and the fourth switch, the second switch and the third switch are switched off.