Abstract: A plug connector for the mechanical and electrical connection to cable plugs of data cables has a housing (2) having at least one plug-in opening (1) for a complementary plug connector. Multiple electrical contact elements (5) protrude into the plug-in opening (1) and are guided on the rear side of the housing (2) on its outer side and are connected to a printed circuit board (6) fastened on the outside on the housing (2). The printed circuit board (6) carries a circuit and connection elements (7) for further electronic assemblies. This circuit on the printed circuit board (6) includes an assembly for galvanic isolation of the network signals, in which at least one chip-LAN transformer (13) mounted on the printed circuit board (6) is provided for each data line.