A 1-tap 10.3125Gb/s Programmable Voltage Mode Line Driver in 28nm CMOS Technology

In this paper, we propose a modified one tap partitioned voltage mode line driver that maintains 50ohms termination impedance across all programmable settings of swings and de-emphasis. The proposed voltage mode line driver achieves this constant termination impedance without the need for a complicated additional circuitry, compared to conventional voltage mode line drivers. Further, the proposed voltage mode line driver employs a linear calibration resistance scheme to meet DC return loss specification better than -20dB across process, voltage and temperature. Additionally, a ripple compensation scheme is presented that regulates the low dropout voltage regulator's output ripple. The prototype voltage mode line driver was designed and implemented in 28nm CMOS technology and supports data rates up to 10.3125Gbps. With a 0.95V supply derived out of low dropout voltage regulator, it dissipates 8mA current for a 950mV pk-pk output swing, with a deterministic jitter of less than 5ps.