Pair-wise staggering transmitter for single-ended parallel signaling

A novel pair-wise staggering transmitter is proposed to reduce the crosstalk noise in single-ended channels at high data rates. This work considers two neighboring channels as a pair, and applies staggering between adjacent pairs. As a result, the peak power of crosstalk-induced jitter (CIJ) and glitch (CIG) are reduced by half, so eye becomes larger for a given noise environment, resulting in higher data rate. A prototype IC adopting the proposed approach was fabricated in a 65 nm CMOS process, whose measurement results indicated that the proposed pair-wise 1/2-UI staggering substantially improved the eye height and width at measured operating range of 4.4 to 6.0 Gbps as compared to the conventional 1/2-UI staggering. In terms of maximum data rate, the proposed approach was valid up to over 6 Gbps, whereas the conventional approach was valid merely up to around 4.8 Gbps, indicating 25% improvement.