A 1-Tap 40-Gb/s Look-Ahead Decision Feedback Equalizer in 0.18-$muhbox m$SiGe BiCMOS Technology

This paper describes a fully differential 1-tap decision feedback equalizer in 0.18-$muhbox m$SiGe BiCMOS technology. The circuit is capable of equalizing NRZ data up to 40 Gb/s. A look-ahead architecture is employed with modifications to reduce complexity in the high-speed clock distribution. An analog differential voltage controls the tap weights. The design is fabricated in 0.18-$muhbox m$SiGe BiCMOS technology with a 160-GHz$f_T$. It occupies an area of 1.5 mm$,times ,$1 mm and operates from a 3.3-V supply with 230-mA current. It is the first feedback equalizer at 40 Gb/s.