An improved equalization circuit for 10-Gb/s high-speed serial transmission over backplane channel

This paper presents an improved equalization circuit, with a linear equalizer (LE) and a decision feedback equalizer (DFE) in the receiver, for 10-Gb/s high-speed serial data transmission over highly lossy electrical backplane channels. Although DFE provides an effective way to compensate various channel impairments, the pre-cursor inter-symbol interference (ISI) is still a significant problem for channel equalization. With the new equalization method, the pre-cursor ISI is compensated with the linear equalizer, and the post-cursor ISI is cancelled by the DFE. The improved equalization circuit with programmable linear equalizer and a 3-tap DFE is implemented to work at 10-Gb/s and compensate the channel loss of -20 dB. The results show it outperform a traditional 5-tap DFE in vertical eye-opening.