A 3.12 pJ/bit, 19–27 Gbps receiver with 2 Tap-DFE embedded clock and data recovery

A 19-27-Gb/s receiver comprising of a continuous time linear equalizer (CTLE) followed by a 2 tap decision feedback equalizer embedded clock and data recovery circuit is implemented. The hybrid CDR is operated at half rate, which is incorporated into a broad band PLL to facilitate ISI and jitter suppression over wide band operation. A quadrature relaxation type oscillator is proposed to provide the sampling phases without bulky inductors. Fabricated in a 40 nm CMOS technology, the whole receiver manifests a high energy efficiency of 3.12pJ/bit at 27 Gbps operation to compensate 20 dB channel loss at Nyquist frequency. The core area is 0.09 mm² only.