A 50 Gb/s Adaptive ADFE with SNR Based Power Management for 2-PAM Systems

Abstract

A 50Gbls all-digital adaptive noise-suppression (NS) feed-forward equalizer (AFFE) and adaptive decision feedback equalizer (ADFE) for 2-level pulse amplitude modulation (2-PAM) serial link systems with SNR based power management scheme is presented. Based on a parallel extended incremental coefficients-lookahead scheme (EICL), we propose a reconfigurable Dual Data paths Self-Lookahead Filter (DD-SLF) for ADFE. SNR-power management skill is adopted to adaptively adjust the hardware configuration in different channel environment and SNR to achieve optimum energy efficiency. The whole equalizer which operates at 1 GHz system clock rate with 50 parallelisms is implemented in 40nm CMOS technology with a core area 0.38mm(2). The equalizer with 50Gb/s throughput rate achieves 2.6pJ/bit energy efficiency under 0.81V supply measurement results.