Planar filter, in particular for multiple-pole plug connectors having a

Abstract

A planar filter, in particular for multiple-pole plug connectors (plugs or counterpart plugs) disposed in a housing making a ground connection, for signal lines carrying electronic signals, includes a substrate and a number of closely spaced capacitors corresponding to the number of signal lines and being disposed on the substrate. The capacitors are formed of one common ground electrode being substantially continuous at least in the peripheral region of the substrate, individual signal electrodes each being provided for one of the signal lines and being insulated from the others, and a dielectric layer between them. The substrate has openings formed therein each for one of the signal lines. The signal electrodes each extend to or into one of the openings and are connected there to one of the signal lines. Each of the capacitors is formed of a series circuit of two substantially equal-size individual capacitors forming a capacitor pair. Intermediate electrodes are applied onto the dielectric covering of the signal electrodes and to the ground electrode for forming the two series-connected capacitors, they cover both of them over approximately equal-sized area regions, and they cover the ground electrode and the associated signal electrodes with portions of approximately equal area.