A hybrid electromagnetic bandgap (EBG) structure for broadband suppression
of noise on printed wiring boards includes an array of coplanar patches
interconnected into a grid by series inductances, and a corresponding
array of shunt LC networks connecting the coplanar patches to a second
conductive plane. This combination of series inductances and shunt
resonant vias lowers the cutoff frequency for the fundamental stopband.
The series inductances and shunt capacitances may be implemented using
surface mount component technology, or printed traces. Patches may also
be interconnected by coplanar coupled transmission lines. The even and
odd mode impedances of the coupled lines may be increased by forming
slots in the second conductive plane disposed opposite to the
transmission line, lowering the cutoff frequency and increasing the
bandwidth of the fundamental stopband. Coplanar EBG structures may be
integrated into power distribution networks of printed wiring boards for
broadband suppression of electromagnetic noise.