30.2 A 161mW 56Gb/s ADC-Based Discrete Multitone Wireline Receiver Data-Path in 14nm FinFET

The increasing demand on bandwidth for communicating among processors through wired interconnects in large-scale servers motivates the increase in the lane-data-rate from the current 28Gb/s to 56Gb/s or further. Recently published works [1]–[3] demonstrated ADC-based receiver (RX) prototypes equalizing $\gt 56$ Gb/s PAM-4 symbols for legacy channels with pre-FEC BERs of less than 2E-4 satisfying IEEE p802.bj/bs pre-FEC BER requirements. While the ADC-based $\gt 56$ Gb/s PAM-4 RXs provide strong equalization performance using a large number of feed-forward equalization (FFE) taps and a few decision-feedback equalization (DFE) taps [1], [2] implemented in digital, their power consumption remains excessive due to heavy arithmetic operations in the DSP.