Co-design importance for over 20Gbps I/O interface

To achieve high performance communication it is necessary to consider all the design parameters for the switching circuit, interconnection and power supply. As these parameters definitely affect each other for over 20Gbps. These must be included for their optimization. These parameters are driver on-resistance (drivability), characteristic impedance of all connection routs, dependent frequency load with termination condition, receiver sensitivity and input impedance of power source within 1/4 wave length. Synopsys HSPICE is used for the simulation of the I/O interfaces with actual measurement S-parameter and 65nm process node in the TSMC IP's. In our study, we concluded that the power source line should be low impedance transmission line even 1mm length as similar as 1/4 wavelengths.