A 6-Gbps/lane receiver for a clock-forwarded link in 65-nm CMOS process

Abstract

For a 6-Gbps/lane clock-forwarded link, a wireline receiver has been developed. The phases of the sampling clocks are aligned to the center of the input data eye by a clock and data recovery (CDR) circuit. In the CDR circuit, the sampling clock phases are rotated by a phase rotating phase locked loop (PLL). A three-tap decision feedback equalizer (DFE) compensates for the loss of cable together with a continuous-time linear equalizer (CTLE) to ensure sufficient eye opening for the CDR circuit to find the optimum sampling phase. The DFE coefficients are adaptively calculated based on the data and edge samples. Implemented in a 65-nm CMOS process, the three-lane 6-Gbps/lane receiver for a clock-forwarded link occupies 0.63mm(2) including pads and consumes 288mA from a 1.2-V supply. Copyright (c) 2015 John Wiley Sons, Ltd.