Lower cutoff frequency improvement of planar EBG-patterned PDN using edge termination

A designed, fabricated and tested electromagnetic bandgap (EBG) structure is proposed for resolving the problem of the lower cut-off frequency of conventional planar-type EBGs. Bandwidth enhancement is achieved by incorporating edge termination along the edges of the whole EBG-patterned power plane. Measurement results show that the lower cutoff frequency is shifted downwards from 800 to 13 MHz. This structure also improves the upper cutoff frequency of 4.3 GHz for the conventional planar EBG to 5.2 GHz. Using this structure, simultaneous switching noise can be suppressed over the relative bandwidth of 63%, which is higher than the commonly used EBGs. The structure is easily fabricated with the current method of printed circuit board manufacturing processes and commonly used SMD resistors and capacitors.