Design of CPO Daughter Board with FPGA and 25-Gbaud × 16-Channel Ultra-Compact Optical Transceivers

We design a CPO daughter board on which 32 ultra-compact transceivers are mounted with an FPGA. The high-speed differential transmission lines are designed with the aid of electro-magnetic simulations. Eye diagrams are simulated by high-speed circuit simulations. Measured 25-Gbaud NRZ eye diagrams have a good agreement with the simulated results. Electrical crosstalk was suppressed to −30 dB and lower. The simulated eye diagrams have no degradation even activating the aggressors.