PAM-4 Driver Amplifier using Distributed Power Combining

Abstract

We present a comparison of two analog driver circuits for optical communication with integrated distributed PAM-4 power combination. They achieve low group delay variations across a bandwidth of up to 102 GHz, while consuming less than 122mW. Eye diagram measurements at data rates of 140 Gb/s demonstrate the potential of the presented amplifier for next generation high data rate communication systems, showing the highest data rate compared to similar circuit approaches.