A novel 6-Gbps half-rate SST transmitter with impedance calibration and adjustable pre-emphasis

A novel half-rate source-series-terminated (SST) transmitter in 65nm bulk CMOS technology is presented in this paper. Compared to previous half-rate SST transmitters, the proposed one consists of four binary-weighted slices increasing proportionally as 1x, 2x, 4x and 8x and the range of pre-emphasis level is increased greatly by the clock-match block to adapt to different channel. The half-rate transmitter can adjust the pre-emphasis level from 1.2dB to 23dB. The transmitter output impedance is adjustable from 33ohms to 64ohms. A power consumption of 24mW is measured at a transmit rate of 6 GB/s which is power-efficient compared to previous half-rate SST transmitter.