A 5.9mW/Gb/s 7Gb/s/pin 8-lane single-ended RX with crosstalk cancellation scheme using a XCTLE and 56-tap XDFE in 32nm SOI CMOS

Abstract

This work reports an 8-lane single-ended RX featuring compact and low power far-end crosstalk (FEXT) cancellation circuits. The RX data-path consists of a cross continuous-time linear equalizer (XCTLE) to remove FEXT by nearest aggressors within the channel bundle. Residual post-cursor FEXT is suppressed by a direct feedback 7x8-tap cross decision-feedback equalizer (XDFE). A CTLE and 8-tap DFE equalize single-ended channels with 28dB insertion loss at Nyquist frequency without TX FFE. The circuit, fabricated in 32nm SOI CMOS, was measured to receive 7Gb/s/pin PRBS11 data at BER< 10-12 with 12.5%UI margin. Itoccupies 300×350μm2 with an energy efficiency of 5.9mW/Gb/s.