A switching amplifier includes an input end for receiving an input signal, a reference signal reception end for receiving a reference signal, a feedback end for receiving a feedback signal, an output end for outputting an output signal, an integration circuit for performing integration operation on the input signal according to the output signal and the feedback signal, so as to generate an integration result, a comparison circuit coupled to the integration circuit, the reference signal end, and the output end, for comparing the integration result and the reference signal, so as to generate the output signal for the output end, and a feedback circuit coupled between an output end of the integration circuit and the feedback end, for generating the feedback signal for the feedback end to clamp the integration result to a predetermined value when the integration result reaches the predetermined value.