An Adaptation Engine for a 2x Blind ADC-Based CDR in 65 nm CMOS

This paper proposes an adaptation engine for a 2 blind sampling ADC-based receiver. The proposed adaptive engine uses a triangular desired waveform, instead of two fixed desired levels, to shape the equalizer output in spite of blind nature of sampling. The measured results confirm the adaptive engine restores a 5 Gb/s eye subjected to 13 dB of attenuation at Nyquist frequency to an equivalent of 320 mV of vertical opening. The receiver consumes 192 mW, out of which 78 mW is used by the digital CDR.