A configurable 2-Gbps LVDS transceiver in 150-nm CMOS with pre-emphasis, equalization, and slew rate control

摘要

A configurable full-duplex low-voltage differential signaling transceiver is presented, which can be configured to operate either for smaller differential channels (a few inches of striplines) or for longer channels (10 m of twisted pair cables). The configurability is embedded in the form of functionalities like pre-emphasis, equalization, and slew rate control within the transceiver. The transmitter employs a hybrid voltage-current-mode driver, which due to replica action, achieves a high-impedance current-mode signal dispatch and at the same time provides a matched impedance at the near end for improved intersymbol interference. The transmitter achieves slew rate control through a band-limited pre-driver, while the pre-emphasis is achieved through a capacitive feed-forward. The receiver employs a large-input common-mode first stage enclosed in a common-mode control loop that enables its first stage to also act like a domain shifter (VDDIO-to-VDDCORE) reducing the overall power consumption. The equalization in the receiver is implemented by using carefully sized active inductive loads inside the receiver. The transceiver is designed and fabricated in 150-nm complementary metal-oxide-semiconductor, sharing the space with a larger die, occupying an area of 400 x 400 mu m. The measurement results demonstrate that the transceiver is operating at 2 Gbps both for a 4-in microstrip and a 10-m twisted pair CAT6 cable with 30 and 180 ps of total jitter, respectively. The built-in impedance calibrator minimizes the spread in the on-die termination at the near end provided by the transmitter-minimizing bit error rate across process, voltage, and temperature corners. The transmitter consumes a total power of 17 mW operating at 2 Gbps, that is, 8.5 pJ/bit of energy consumption; the receiver consumes a total power of 3.5 mW while driving a load of 5 pF at 2 Gbps. Copyright (C) 2016 John Wiley & Sons, Ltd.