A switching amplifier includes a plurality of cascade elements, each bridge circuit includes an inductive load coupled between a first leg terminal of one of the at least two leg circuits and a second leg terminal of another one of the at least two leg circuits. A first leg voltage of the first leg terminal have a phase shift relative to a second leg voltage of the second leg terminal, the phase shift is used for causing the inductive load to store electric energy and generating a minimum circulating current−I min or I min sufficient to effect conducting of a corresponding diode; each of the switches is configured to be turned on if the corresponding diode conducts current to effect zero voltage switching of the corresponding switch. The minimum circulating current−I min or I min is equal to a constant value.