106 Gb/s PAM-4 Transmitter With 2.1 Vppd Swing in 7nm FinFET Process

This paper demonstrates a high swing 106Gb/s PAM-4 transmitter in 7nm FinFET process. The 7-bit DAC based transmitter is designed to directly drive a range of TOSAs in either single ended or differential configuration eliminating the cost and power of an additional laser driver IC. Using a 2.4V supply, it achieves 2.1V pp differential and 1.05V pp single-ended swing across a 50Ω load. Total power consumption of the transmitter was found to be 2.63 pJ/bit with 2.4V supply and 2.23 pJ/b with 1.5 V supply and external bias-T.