In a filter circuit (6) with a low-pass filter (7), the output of the low-pass filter (7) is regenerated over a reverse current diode (11) with the input of the low-pass filter or of a further low-pass filter (8) pre-connected to the low-pass filter (7). A circuit arrangement includes such a filter circuit (6) and a battery charger circuit (1) with a battery (2) and a d.c. generator (A).