The invention relates to an on-board charger (1) for charging a high-voltage battery (8), wherein the on-board mains charger (1) comprises a rectifier (3) and an inverter (4), wherein the inverter (4) is connected to a first primary inductivity (LP1) and a second primary inductivity (LP2), wherein a first secondary inductivity (LS1) is assigned to the first primary inductivity (LP1) and a second secondary inductivity (LS2) is assigned to the second primary inductivity (LP2), wherein a first rectifier (5) is assigned to the first secondary inductivity (LS1) and a second rectifier (6) is assigned to the second secondary inductivity (LS2), wherein a positive terminal of the first rectifier (5) and a negative terminal of the second rectifier (6) is connected to the high-voltage battery (8), wherein the winding ratio of the primary and secondary inductivities (LP1, LP2, LS1, LS2) is selected such that the first converter consisting of first primary and secondary inductivity (LP1, LS1) transfers a multiple of power compared to the second converter consisting of second primary and secondary inductivity (LP2, LS2), wherein on the secondary side of the first secondary inductivity (LS1) two further secondary inductivities (LS3, LS4) with downstream rectifier (9) are arranged and on the secondary side of the second secondary inductivity (LS2) two further secondary inductivities (LS5, LS6) with downstream rectifier (10) are arranged, wherein the rectifiers (9, 10) are connected to an on-board network with at least one low-voltage battery (LV).
