Abstract: According to the physical mechanism and the equivalent circuit model of the planar Electromagnetic Band-Gap (EBG) structure, a novel planar EBG structure named CBS-EBG for Simultaneous Switching Noise (SSN) suppression in high-speed circuits is proposed by introducing the special C-shaped Bridges and Slits (CBS). Real-data experiment shows that 40 dB stopband is realized from 296 MHz~15 GHz. Compared with the LBS-EBG structure, the lower cutoff frequency decreases from 432 MHz to 296 MHz with a similar higher frequency range performance, and a lower band-gap center frequency is realized. The transfer characteristic of the signal under localized CBS-EBG is studied. Simulation and measurement are performed to verify the high performance of the proposed CBS-EBG both in SSN suppression and signal integrity with the local topology and appropriate routing policy.