Electrical vehicle circuitry

A transformer circuit 610 for an electric vehicle comprises: an input for receiving electrical energy; an output 521 for providing electrical energy to an electrical bus of the vehicle at an output voltage; and a DCDC converter 505 disposed between the input and output. The DCDC converter comprises: a transformer 510 with primary and secondary windings 512, 514; a primary side circuit 550 connecting the input to the primary winding; and a secondary side circuit 570-A connecting the secondary winding to the output. The input comprises an AC charging input 530 that provides electrical energy to an ACDC converter 540 that provides electrical energy to the primary winding via the primary side circuit. The input also comprises a DC charging input 560 between ACDC converter and primary side circuit. The DC charging input receives electrical energy from a DC source and provides it to the primary winding via the primary side circuit. The DCDC converter may include a further secondary side circuit 570-B that provides electrical energy to a further electrical bus of the vehicle at a further output voltage, wherein the transformer is a multi-coil transformer comprising a further secondary winding 516 connected to a further output 531 via the further secondary side circuit.