A 0.18µm CMOS 12Gb/s 10-PAM Serial Link Transmitter

Abstract

A 12Gb/s 10-level pulse amplitude modulation (PAM) serial-link transmitter was implemented using a 0.18µm CMOS process. The proposed 10-PAM transmitter achieves a channel efficiency of 4bit/symbol by dual-mode amplitude modulations using 10 differential-mode levels and 3 common-mode levels. The measured maximum data-rate was 12Gb/s over 0.7-m cable and 2-cm printed circuit board (PCB) traces. The entire transmitter consumes 432mW such that the figure of merit of the transmitter is 36pJ/bit. The present work demonstrates the greater channel efficiency of 4bit/symbol than the currently reported multi-level PAM transmitters.