A 12.5-Gb/s Near-Ground Transceiver Employing a MaxEye Algorithm-Based Adaptation Technique

A 12.5-Gb/s complete near-ground transceiver is demonstrated. The output stage of the transmitter (TX) employs 2-tap finite-impulse response equalization (EQ) and also performs ac-coupled EQ for an additional EQ. A continuous-time linear equalizer (CTLE) on the receiver (RX) side compensates for the channel attenuation. Based on the maximum eye algorithm, the peaking gain of CTLE is adaptively controlled to track a time-variant environment, such as PVT variations. Each TX and RX is implemented with clocking circuits: a differential PLL, and a dual-loop clock and data recovery circuit. The proposed transceiver is fabricated in a 45-nm CMOS process, and the entire TX and RX, respectively, consume 92 and 138 mW under a 1.2-V supply while operating at 12.5 Gb/s.