10 Gb/s transmit equalizer using duobinary signaling over FR4 backplane

A 10 Gb/s 6-tap transmit equalizer based on partial response signaling for high speed backplane transmission is presented.By combining features of equalizer and frequency-dependent channel, duobinary signaling can be generated at the output of FR4 backplane, aiming at increasing data rate while reducing design complexity.Based on 0.18μm CMOS technology, this equalizer has been de-signed and fabricated, in which both variable capacitor and load resistor calibration techniques are explored to eliminate the effect of process variations.The chip occupies 0.68 ×0.8mm2 including I/O pads and consumes a power of 194mW with 1.8V power supply.Measurement results show that a typical 3-level eye diagram can be obtained at the receiver and the equalizer can work properly at the data rate of 10Gb/s.