The invention relates to a filter circuit (200) comprising at least a first filter line (210). The first filter line (210) has a first input circuit (10), a first integration circuit (20) and a first output circuit (30). The first input circuit (10) is configured in such a way that, as a function of the value of the input signal, it converts an input signal into at least two distinguishable, first first-stage output signals and relays the first-stage output signals to the first integration circuit (20, 240) during a prescribed period of time. The first integration circuit (20) is configured to integrate the first first-stage output signals of the first input circuit (10) over the prescribed period of time and to generate a first integration signal (25). The first output circuit (25) is configured to compare the first integration signal (25) to a first output reference value and to generate a first second-stage output signal (35). The invention also relates to an appertaining filtering method.