Packaged clock recovery integrated circuits for 40 Gbit/s optical communication links

Abstract

Three packaged clock recovery integrated circuits: a differentiate/rectify circuit, a delay/multiply circuit, and a phase detector circuit, were implemented in an advanced AlGaAs-GaAs HBT process. The packaged ICs show performance adequate for clock recovery for optical communication links of up to at least 40 Gbit/s. With a 30 Gbit/s pseudo-random sequence input, a phase-locked loop incorporating these ICs readily acquired and maintained phase lock, demonstrating the excellent system performance of these components.