A 16-Channel Optical Receiver Circuit for a Multicore Fiber-Based Co-Packaged Optics Module in a 65-nm CMOS Chip

Co-packaged optics (CPO) modules have been studied and developed for improving data capacity and reducing power consumption of data-center optical communications. In this paper, we present a 16-channel optical receiver circuit for a multicore fiber (MCF)-based CPO module in a single 65-nm CMOS chip. This chip consists of 16-channel receiver circuits, received signal strength indicators (RSSIs) and power-supply noise filters for photo detectors. Characteristics of the fabricated receiver chip using the 65-nm CMOS process were evaluated by on-wafer probing, and clear eye openings of the electrical output at 25 Gb/s were obtained in all 16-channel receivers. Additionally, an energy efficiency of 1.3 pJ/b/ch was obtained. The measurement results show that our optical receiver is suitable for MCF-based CPO modules considering both the bit rate and the arrangement of the circuit blocks.