A 1.62/2.7-Gb/s Adaptive Transmitter With Two-Tap Preemphasis Using a Propagation-Time Detector

A 1.62/2.7-Gb/s adaptive transmitter with two-tap preemphasis is presented. The tap coefficients are adjusted by detecting the propagation time through the channel with different lengths. This adaptive transmitter is fabricated in 0.13-??m CMOS technology, and the core area occupies 0.25 ?? 0.15 mm². The maximum power consumption from a 1.2-V supply is 32.4 mW at 2.7 Gb/s. For a 40-in FR4 PCB trace with a 12.3-dB loss, the measured RMS and peak-to-peak jitters of the recovered data are 30 and 231 ps, respectively, for a 1.62-Gb/s pseudorandom binary sequence (PRBS) of 2³¹ - 1. For a 20-in FR4 PCB trace with a 10.6-dB loss, the RMS and peak-to-peak jitters are 21 and 144 ps, respectively, for a 2.7-Gb/s PRBS of 2³¹ - 1. For both cases, the measured bit error rates are less than 10^-12.