A mixed-signal decision-feedback equalizer that uses a look-ahead architecture

A mixed-signal decision-feedback equalizer (DFE) that uses a look-ahead architecture is described. The parallelism in the look-ahead DFE (LA DFE) achieves an increase in the data rate over a conventional DFE with a small increase in area. Fully differential analog circuits perform the convolution operation in the LA DFE, and the coefficient adaption is carried out by digital circuits. The LA DFE occupies 23 mm/sup 2/ in a 2-/spl mu/m CMOS process and operates at 50 Mb/s while dissipating 260 mW.

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