Energy Efficient Bidirectional Equalized Transceiver with PVT Insensitive Active Termination

摘要

This paper presents a current-mode bidirectional transceiver for off-chip interconnects, which deploys a feed-forward equalization (FFE) scheme in transmitter for channel-loss compensation. The proposed transmitter makes use of a current-boosting driver (CBD) which boosts the pre-drive current, increasing the current-efficiency of the transmitter compared to the conventional CML driver. Moreover, compared to conventional passive terminated transceivers, the proposed transceiver utilizes an active termination in combination with a special biasing scheme, thereby making the termination impedance insensitive to process-voltage-temperature (PVT) variations. The entire architecture has been designed in 180 nm CMOS technology with a supply voltage of 1.8 V. Simulated power consumption in the transceiver pair is 6.4 mW with an energy efficiency of 1.28 pJ/bit while operating at 5 Gbps over 52-inch FR4 PCB trace having loss of 24.4 dB at one-half the bitrate.