Abstract: A configurable transformer module includes a primary printed circuit board, one or more secondary printed circuit boards, and one or more interface connectors. The primary PCB has planar primary windings formed thereon and openings for accommodating a planar transformer core. Each of the one or more secondary PCB has planar secondary windings and an opening for accommodating the planar transformer core. Some of the secondary PCB has mating terminals formed thereon. The planar secondary windings on a respective secondary printed circuit board are configured by electrical connections provided at a respective interface connector to realize a given transformer turns ratio between the respective secondary printed circuit board and the primary printed circuit board.